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// stb_truetype.h - v1.12 - public domain
// authored from 2009-2016 by Sean Barrett / RAD Game Tools
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//
//   This library processes TrueType files:
//        parse files
//        extract glyph metrics
//        extract glyph shapes
//        render glyphs to one-channel bitmaps with antialiasing (box filter)
//
//   Todo:
//        non-MS cmaps
//        crashproof on bad data
//        hinting? (no longer patented)
//        cleartype-style AA?
//        optimize: use simple memory allocator for intermediates
//        optimize: build edge-list directly from curves
//        optimize: rasterize directly from curves?
//
// ADDITIONAL CONTRIBUTORS
//
//   Mikko Mononen: compound shape support, more cmap formats
//   Tor Andersson: kerning, subpixel rendering
//
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//   Misc other:
//       Ryan Gordon
//       Simon Glass
//
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//   Bug/warning reports/fixes:
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//       "Zer" on mollyrocket (with fix)
//       Cass Everitt
//       stoiko (Haemimont Games)
//       Brian Hook 
//       Walter van Niftrik
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//       David Gow
//       David Given
//       Ivan-Assen Ivanov
//       Anthony Pesch
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//       Johan Duparc
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//       Hou Qiming
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//       Fabian "ryg" Giesen
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//       Martins Mozeiko
//       Cap Petschulat
//       Omar Cornut
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//       github:aloucks
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//       Peter LaValle
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credits  
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//       Sergey Popov
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//       Giumo X. Clanjor
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//       Higor Euripedes
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//       Thomas Fields
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//       Derek Vinyard
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//
// VERSION HISTORY
//
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//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
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//   1.11 (2016-04-02) fix unused-variable warning
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//   1.10 (2016-04-02) user-defined fabs(); rare memory leak; remove duplicate typedef
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//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use allocation userdata properly
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//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
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//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
//                     variant PackFontRanges to pack and render in separate phases;
//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
//                     fixed an assert() bug in the new rasterizer
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//                     replace assert() with STBTT_assert() in new rasterizer
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//
//   Full history can be found at the end of this file.
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//
// LICENSE
//
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//   This software is dual-licensed to the public domain and under the following
//   license: you are granted a perpetual, irrevocable license to copy, modify,
//   publish, and distribute this file as you see fit.
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//
// USAGE
//
//   Include this file in whatever places neeed to refer to it. In ONE C/C++
//   file, write:
//      #define STB_TRUETYPE_IMPLEMENTATION
//   before the #include of this file. This expands out the actual
//   implementation into that C/C++ file.
//
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//   To make the implementation private to the file that generates the implementation,
//      #define STBTT_STATIC
//
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//   Simple 3D API (don't ship this, but it's fine for tools and quick start)
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//           stbtt_BakeFontBitmap()               -- bake a font to a bitmap for use as texture
//           stbtt_GetBakedQuad()                 -- compute quad to draw for a given char
//
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//   Improved 3D API (more shippable):
//           #include "stb_rect_pack.h"           -- optional, but you really want it
//           stbtt_PackBegin()
//           stbtt_PackSetOversample()            -- for improved quality on small fonts
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//           stbtt_PackFontRanges()               -- pack and renders
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//           stbtt_PackEnd()
//           stbtt_GetPackedQuad()
//
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//   "Load" a font file from a memory buffer (you have to keep the buffer loaded)
//           stbtt_InitFont()
//           stbtt_GetFontOffsetForIndex()        -- use for TTC font collections
//
//   Render a unicode codepoint to a bitmap
//           stbtt_GetCodepointBitmap()           -- allocates and returns a bitmap
//           stbtt_MakeCodepointBitmap()          -- renders into bitmap you provide
//           stbtt_GetCodepointBitmapBox()        -- how big the bitmap must be
//
//   Character advance/positioning
//           stbtt_GetCodepointHMetrics()
//           stbtt_GetFontVMetrics()
//           stbtt_GetCodepointKernAdvance()
//
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//   Starting with version 1.06, the rasterizer was replaced with a new,
//   faster and generally-more-precise rasterizer. The new rasterizer more
//   accurately measures pixel coverage for anti-aliasing, except in the case
//   where multiple shapes overlap, in which case it overestimates the AA pixel
//   coverage. Thus, anti-aliasing of intersecting shapes may look wrong. If
//   this turns out to be a problem, you can re-enable the old rasterizer with
//        #define STBTT_RASTERIZER_VERSION 1
//   which will incur about a 15% speed hit.
//
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// ADDITIONAL DOCUMENTATION
//
//   Immediately after this block comment are a series of sample programs.
//
//   After the sample programs is the "header file" section. This section
//   includes documentation for each API function.
//
//   Some important concepts to understand to use this library:
//
//      Codepoint
//         Characters are defined by unicode codepoints, e.g. 65 is
//         uppercase A, 231 is lowercase c with a cedilla, 0x7e30 is
//         the hiragana for "ma".
//
//      Glyph
//         A visual character shape (every codepoint is rendered as
//         some glyph)
//
//      Glyph index
//         A font-specific integer ID representing a glyph
//
//      Baseline
//         Glyph shapes are defined relative to a baseline, which is the
//         bottom of uppercase characters. Characters extend both above
//         and below the baseline.
//
//      Current Point
//         As you draw text to the screen, you keep track of a "current point"
//         which is the origin of each character. The current point's vertical
//         position is the baseline. Even "baked fonts" use this model.
//
//      Vertical Font Metrics
//         The vertical qualities of the font, used to vertically position
//         and space the characters. See docs for stbtt_GetFontVMetrics.
//
//      Font Size in Pixels or Points
//         The preferred interface for specifying font sizes in stb_truetype
//         is to specify how tall the font's vertical extent should be in pixels.
//         If that sounds good enough, skip the next paragraph.
//
//         Most font APIs instead use "points", which are a common typographic
//         measurement for describing font size, defined as 72 points per inch.
//         stb_truetype provides a point API for compatibility. However, true
//         "per inch" conventions don't make much sense on computer displays
//         since they different monitors have different number of pixels per
//         inch. For example, Windows traditionally uses a convention that
//         there are 96 pixels per inch, thus making 'inch' measurements have
//         nothing to do with inches, and thus effectively defining a point to
//         be 1.333 pixels. Additionally, the TrueType font data provides
//         an explicit scale factor to scale a given font's glyphs to points,
//         but the author has observed that this scale factor is often wrong
//         for non-commercial fonts, thus making fonts scaled in points
//         according to the TrueType spec incoherently sized in practice.
//
// ADVANCED USAGE
//
//   Quality:
//
//    - Use the functions with Subpixel at the end to allow your characters
//      to have subpixel positioning. Since the font is anti-aliased, not
//      hinted, this is very import for quality. (This is not possible with
//      baked fonts.)
//
//    - Kerning is now supported, and if you're supporting subpixel rendering
//      then kerning is worth using to give your text a polished look.
//
//   Performance:
//
//    - Convert Unicode codepoints to glyph indexes and operate on the glyphs;
//      if you don't do this, stb_truetype is forced to do the conversion on
//      every call.
//
//    - There are a lot of memory allocations. We should modify it to take
//      a temp buffer and allocate from the temp buffer (without freeing),
//      should help performance a lot.
//
// NOTES
//
//   The system uses the raw data found in the .ttf file without changing it
//   and without building auxiliary data structures. This is a bit inefficient
//   on little-endian systems (the data is big-endian), but assuming you're
//   caching the bitmaps or glyph shapes this shouldn't be a big deal.
//
//   It appears to be very hard to programmatically determine what font a
//   given file is in a general way. I provide an API for this, but I don't
//   recommend it.
//
//
// SOURCE STATISTICS (based on v0.6c, 2050 LOC)
//
//   Documentation & header file        520 LOC  \___ 660 LOC documentation
//   Sample code                        140 LOC  /
//   Truetype parsing                   620 LOC  ---- 620 LOC TrueType
//   Software rasterization             240 LOC  \                           .
//   Curve tesselation                  120 LOC   \__ 550 LOC Bitmap creation
//   Bitmap management                  100 LOC   /
//   Baked bitmap interface              70 LOC  /
//   Font name matching & access        150 LOC  ---- 150 
//   C runtime library abstraction       60 LOC  ----  60
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//
//
// PERFORMANCE MEASUREMENTS FOR 1.06:
//
//                      32-bit     64-bit
//   Previous release:  8.83 s     7.68 s
//   Pool allocations:  7.72 s     6.34 s
//   Inline sort     :  6.54 s     5.65 s
//   New rasterizer  :  5.63 s     5.00 s
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//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
////
////  SAMPLE PROGRAMS
////
//
//  Incomplete text-in-3d-api example, which draws quads properly aligned to be lossless
//
#if 0
#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
#include "stb_truetype.h"

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unsigned char ttf_buffer[1<<20];
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unsigned char temp_bitmap[512*512];

stbtt_bakedchar cdata[96]; // ASCII 32..126 is 95 glyphs
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GLuint ftex;
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void my_stbtt_initfont(void)
{
   fread(ttf_buffer, 1, 1<<20, fopen("c:/windows/fonts/times.ttf", "rb"));
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   stbtt_BakeFontBitmap(ttf_buffer,0, 32.0, temp_bitmap,512,512, 32,96, cdata); // no guarantee this fits!
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   // can free ttf_buffer at this point
   glGenTextures(1, &ftex);
   glBindTexture(GL_TEXTURE_2D, ftex);
   glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, 512,512, 0, GL_ALPHA, GL_UNSIGNED_BYTE, temp_bitmap);
   // can free temp_bitmap at this point
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
}

void my_stbtt_print(float x, float y, char *text)
{
   // assume orthographic projection with units = screen pixels, origin at top left
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   glEnable(GL_TEXTURE_2D);
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   glBindTexture(GL_TEXTURE_2D, ftex);
   glBegin(GL_QUADS);
   while (*text) {
      if (*text >= 32 && *text < 128) {
         stbtt_aligned_quad q;
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         stbtt_GetBakedQuad(cdata, 512,512, *text-32, &x,&y,&q,1);//1=opengl & d3d10+,0=d3d9
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         glTexCoord2f(q.s0,q.t1); glVertex2f(q.x0,q.y0);
         glTexCoord2f(q.s1,q.t1); glVertex2f(q.x1,q.y0);
         glTexCoord2f(q.s1,q.t0); glVertex2f(q.x1,q.y1);
         glTexCoord2f(q.s0,q.t0); glVertex2f(q.x0,q.y1);
      }
      ++text;
   }
   glEnd();
}
#endif
//
//
//////////////////////////////////////////////////////////////////////////////
//
// Complete program (this compiles): get a single bitmap, print as ASCII art
//
#if 0
#include <stdio.h>
#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
#include "stb_truetype.h"

char ttf_buffer[1<<25];

int main(int argc, char **argv)
{
   stbtt_fontinfo font;
   unsigned char *bitmap;
   int w,h,i,j,c = (argc > 1 ? atoi(argv[1]) : 'a'), s = (argc > 2 ? atoi(argv[2]) : 20);

   fread(ttf_buffer, 1, 1<<25, fopen(argc > 3 ? argv[3] : "c:/windows/fonts/arialbd.ttf", "rb"));

   stbtt_InitFont(&font, ttf_buffer, stbtt_GetFontOffsetForIndex(ttf_buffer,0));
   bitmap = stbtt_GetCodepointBitmap(&font, 0,stbtt_ScaleForPixelHeight(&font, s), c, &w, &h, 0,0);

   for (j=0; j < h; ++j) {
      for (i=0; i < w; ++i)
         putchar(" .:ioVM@"[bitmap[j*w+i]>>5]);
      putchar('\n');
   }
   return 0;
}
#endif 
//
// Output:
//
//     .ii.
//    @@@@@@.
//   V@Mio@@o
//   :i.  V@V
//     :oM@@M
//   :@@@MM@M
//   @@o  o@M
//  :@@.  M@M
//   @@@o@@@@
//   :M@@V:@@.
//  
//////////////////////////////////////////////////////////////////////////////
// 
// Complete program: print "Hello World!" banner, with bugs
//
#if 0
char buffer[24<<20];
unsigned char screen[20][79];

int main(int arg, char **argv)
{
   stbtt_fontinfo font;
   int i,j,ascent,baseline,ch=0;
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   float scale, xpos=2; // leave a little padding in case the character extends left
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   char *text = "Heljo World!"; // intentionally misspelled to show 'lj' brokenness
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   fread(buffer, 1, 1000000, fopen("c:/windows/fonts/arialbd.ttf", "rb"));
   stbtt_InitFont(&font, buffer, 0);

   scale = stbtt_ScaleForPixelHeight(&font, 15);
   stbtt_GetFontVMetrics(&font, &ascent,0,0);
   baseline = (int) (ascent*scale);

   while (text[ch]) {
      int advance,lsb,x0,y0,x1,y1;
      float x_shift = xpos - (float) floor(xpos);
      stbtt_GetCodepointHMetrics(&font, text[ch], &advance, &lsb);
      stbtt_GetCodepointBitmapBoxSubpixel(&font, text[ch], scale,scale,x_shift,0, &x0,&y0,&x1,&y1);
      stbtt_MakeCodepointBitmapSubpixel(&font, &screen[baseline + y0][(int) xpos + x0], x1-x0,y1-y0, 79, scale,scale,x_shift,0, text[ch]);
      // note that this stomps the old data, so where character boxes overlap (e.g. 'lj') it's wrong
      // because this API is really for baking character bitmaps into textures. if you want to render
      // a sequence of characters, you really need to render each bitmap to a temp buffer, then
      // "alpha blend" that into the working buffer
      xpos += (advance * scale);
      if (text[ch+1])
         xpos += scale*stbtt_GetCodepointKernAdvance(&font, text[ch],text[ch+1]);
      ++ch;
   }

   for (j=0; j < 20; ++j) {
      for (i=0; i < 78; ++i)
         putchar(" .:ioVM@"[screen[j][i]>>5]);
      putchar('\n');
   }

   return 0;
}
#endif


//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
////
////   INTEGRATION WITH YOUR CODEBASE
////
////   The following sections allow you to supply alternate definitions
////   of C library functions used by stb_truetype.

#ifdef STB_TRUETYPE_IMPLEMENTATION
   // #define your own (u)stbtt_int8/16/32 before including to override this
   #ifndef stbtt_uint8
   typedef unsigned char   stbtt_uint8;
   typedef signed   char   stbtt_int8;
   typedef unsigned short  stbtt_uint16;
   typedef signed   short  stbtt_int16;
   typedef unsigned int    stbtt_uint32;
   typedef signed   int    stbtt_int32;
   #endif

   typedef char stbtt__check_size32[sizeof(stbtt_int32)==4 ? 1 : -1];
   typedef char stbtt__check_size16[sizeof(stbtt_int16)==2 ? 1 : -1];

   // #define your own STBTT_ifloor/STBTT_iceil() to avoid math.h
   #ifndef STBTT_ifloor
   #include <math.h>
   #define STBTT_ifloor(x)   ((int) floor(x))
   #define STBTT_iceil(x)    ((int) ceil(x))
   #endif

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   #ifndef STBTT_sqrt
   #include <math.h>
   #define STBTT_sqrt(x)      sqrt(x)
   #endif

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   #ifndef STBTT_fabs
   #include <math.h>
   #define STBTT_fabs(x)      fabs(x)
   #endif

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   // #define your own functions "STBTT_malloc" / "STBTT_free" to avoid malloc.h
   #ifndef STBTT_malloc
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   #include <stdlib.h>
   #define STBTT_malloc(x,u)  ((void)(u),malloc(x))
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   #define STBTT_free(x,u)    ((void)(u),free(x))
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   #endif

   #ifndef STBTT_assert
   #include <assert.h>
   #define STBTT_assert(x)    assert(x)
   #endif

   #ifndef STBTT_strlen
   #include <string.h>
   #define STBTT_strlen(x)    strlen(x)
   #endif

   #ifndef STBTT_memcpy
   #include <memory.h>
   #define STBTT_memcpy       memcpy
   #define STBTT_memset       memset
   #endif
#endif

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
////
////   INTERFACE
////
////

#ifndef __STB_INCLUDE_STB_TRUETYPE_H__
#define __STB_INCLUDE_STB_TRUETYPE_H__

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#ifdef STBTT_STATIC
#define STBTT_DEF static
#else
#define STBTT_DEF extern
#endif

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#ifdef __cplusplus
extern "C" {
#endif

//////////////////////////////////////////////////////////////////////////////
//
// TEXTURE BAKING API
//
// If you use this API, you only have to call two functions ever.
//

typedef struct
{
   unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap
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   float xoff,yoff,xadvance;
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} stbtt_bakedchar;

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STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
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                                float pixel_height,                     // height of font in pixels
                                unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
                                int first_char, int num_chars,          // characters to bake
                                stbtt_bakedchar *chardata);             // you allocate this, it's num_chars long
// if return is positive, the first unused row of the bitmap
// if return is negative, returns the negative of the number of characters that fit
// if return is 0, no characters fit and no rows were used
// This uses a very crappy packing.

typedef struct
{
   float x0,y0,s0,t0; // top-left
   float x1,y1,s1,t1; // bottom-right
} stbtt_aligned_quad;

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STBTT_DEF void stbtt_GetBakedQuad(stbtt_bakedchar *chardata, int pw, int ph,  // same data as above
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                               int char_index,             // character to display
                               float *xpos, float *ypos,   // pointers to current position in screen pixel space
                               stbtt_aligned_quad *q,      // output: quad to draw
                               int opengl_fillrule);       // true if opengl fill rule; false if DX9 or earlier
// Call GetBakedQuad with char_index = 'character - first_char', and it
// creates the quad you need to draw and advances the current position.
//
// The coordinate system used assumes y increases downwards.
//
// Characters will extend both above and below the current position;
// see discussion of "BASELINE" above.
//
// It's inefficient; you might want to c&p it and optimize it.


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//////////////////////////////////////////////////////////////////////////////
//
// NEW TEXTURE BAKING API
//
// This provides options for packing multiple fonts into one atlas, not
// perfectly but better than nothing.

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typedef struct
{
   unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap
   float xoff,yoff,xadvance;
   float xoff2,yoff2;
} stbtt_packedchar;

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typedef struct stbtt_pack_context stbtt_pack_context;
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typedef struct stbtt_fontinfo stbtt_fontinfo;
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#ifndef STB_RECT_PACK_VERSION
typedef struct stbrp_rect stbrp_rect;
#endif
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STBTT_DEF int  stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int width, int height, int stride_in_bytes, int padding, void *alloc_context);
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// Initializes a packing context stored in the passed-in stbtt_pack_context.
// Future calls using this context will pack characters into the bitmap passed
// in here: a 1-channel bitmap that is weight x height. stride_in_bytes is
// the distance from one row to the next (or 0 to mean they are packed tightly
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// together). "padding" is the amount of padding to leave between each
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// character (normally you want '1' for bitmaps you'll use as textures with
// bilinear filtering).
//
// Returns 0 on failure, 1 on success.
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STBTT_DEF void stbtt_PackEnd  (stbtt_pack_context *spc);
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// Cleans up the packing context and frees all memory.

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#define STBTT_POINT_SIZE(x)   (-(x))

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STBTT_DEF int  stbtt_PackFontRange(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, float font_size,
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                                int first_unicode_char_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range);
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// Creates character bitmaps from the font_index'th font found in fontdata (use
// font_index=0 if you don't know what that is). It creates num_chars_in_range
// bitmaps for characters with unicode values starting at first_unicode_char_in_range
// and increasing. Data for how to render them is stored in chardata_for_range;
// pass these to stbtt_GetPackedQuad to get back renderable quads.
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//
// font_size is the full height of the character from ascender to descender,
// as computed by stbtt_ScaleForPixelHeight. To use a point size as computed
// by stbtt_ScaleForMappingEmToPixels, wrap the point size in STBTT_POINT_SIZE()
// and pass that result as 'font_size':
//       ...,                  20 , ... // font max minus min y is 20 pixels tall
//       ..., STBTT_POINT_SIZE(20), ... // 'M' is 20 pixels tall

typedef struct
{
   float font_size;
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   int first_unicode_codepoint_in_range;  // if non-zero, then the chars are continuous, and this is the first codepoint
   int *array_of_unicode_codepoints;       // if non-zero, then this is an array of unicode codepoints
   int num_chars;
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   stbtt_packedchar *chardata_for_range; // output
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   unsigned char h_oversample, v_oversample; // don't set these, they're used internally
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} stbtt_pack_range;
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STBTT_DEF int  stbtt_PackFontRanges(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges);
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// Creates character bitmaps from multiple ranges of characters stored in
// ranges. This will usually create a better-packed bitmap than multiple
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// calls to stbtt_PackFontRange. Note that you can call this multiple
// times within a single PackBegin/PackEnd.
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STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample);
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// Oversampling a font increases the quality by allowing higher-quality subpixel
// positioning, and is especially valuable at smaller text sizes.
//
// This function sets the amount of oversampling for all following calls to
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// stbtt_PackFontRange(s) or stbtt_PackFontRangesGatherRects for a given
// pack context. The default (no oversampling) is achieved by h_oversample=1
// and v_oversample=1. The total number of pixels required is
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// h_oversample*v_oversample larger than the default; for example, 2x2
// oversampling requires 4x the storage of 1x1. For best results, render
// oversampled textures with bilinear filtering. Look at the readme in
// stb/tests/oversample for information about oversampled fonts
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//
// To use with PackFontRangesGather etc., you must set it before calls
// call to PackFontRangesGatherRects.
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STBTT_DEF void stbtt_GetPackedQuad(stbtt_packedchar *chardata, int pw, int ph,  // same data as above
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                               int char_index,             // character to display
                               float *xpos, float *ypos,   // pointers to current position in screen pixel space
                               stbtt_aligned_quad *q,      // output: quad to draw
                               int align_to_integer);

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STBTT_DEF int  stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
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STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects);
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STBTT_DEF int  stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
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// Calling these functions in sequence is roughly equivalent to calling
// stbtt_PackFontRanges(). If you more control over the packing of multiple
// fonts, or if you want to pack custom data into a font texture, take a look
// at the source to of stbtt_PackFontRanges() and create a custom version 
// using these functions, e.g. call GatherRects multiple times,
// building up a single array of rects, then call PackRects once,
// then call RenderIntoRects repeatedly. This may result in a
// better packing than calling PackFontRanges multiple times
// (or it may not).

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// this is an opaque structure that you shouldn't mess with which holds
// all the context needed from PackBegin to PackEnd.
struct stbtt_pack_context {
   void *user_allocator_context;
   void *pack_info;
   int   width;
   int   height;
   int   stride_in_bytes;
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   int   padding;
   unsigned int   h_oversample, v_oversample;
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   unsigned char *pixels;
   void  *nodes;
};

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//////////////////////////////////////////////////////////////////////////////
//
// FONT LOADING
//
//

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STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index);
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// Each .ttf/.ttc file may have more than one font. Each font has a sequential
// index number starting from 0. Call this function to get the font offset for
// a given index; it returns -1 if the index is out of range. A regular .ttf
// file will only define one font and it always be at offset 0, so it will
// return '0' for index 0, and -1 for all other indices. You can just skip
// this step if you know it's that kind of font.


// The following structure is defined publically so you can declare one on
// the stack or as a global or etc, but you should treat it as opaque.
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struct stbtt_fontinfo
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{
   void           * userdata;
   unsigned char  * data;              // pointer to .ttf file
   int              fontstart;         // offset of start of font

   int numGlyphs;                     // number of glyphs, needed for range checking

   int loca,head,glyf,hhea,hmtx,kern; // table locations as offset from start of .ttf
   int index_map;                     // a cmap mapping for our chosen character encoding
   int indexToLocFormat;              // format needed to map from glyph index to glyph
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};
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STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset);
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// Given an offset into the file that defines a font, this function builds
// the necessary cached info for the rest of the system. You must allocate
// the stbtt_fontinfo yourself, and stbtt_InitFont will fill it out. You don't
// need to do anything special to free it, because the contents are pure
// value data with no additional data structures. Returns 0 on failure.


//////////////////////////////////////////////////////////////////////////////
//
// CHARACTER TO GLYPH-INDEX CONVERSIOn

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STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint);
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// If you're going to perform multiple operations on the same character
// and you want a speed-up, call this function with the character you're
// going to process, then use glyph-based functions instead of the
// codepoint-based functions.


//////////////////////////////////////////////////////////////////////////////
//
// CHARACTER PROPERTIES
//

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STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float pixels);
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// computes a scale factor to produce a font whose "height" is 'pixels' tall.
// Height is measured as the distance from the highest ascender to the lowest
// descender; in other words, it's equivalent to calling stbtt_GetFontVMetrics
// and computing:
//       scale = pixels / (ascent - descent)
// so if you prefer to measure height by the ascent only, use a similar calculation.

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STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels);
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// computes a scale factor to produce a font whose EM size is mapped to
// 'pixels' tall. This is probably what traditional APIs compute, but
// I'm not positive.

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STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap);
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// ascent is the coordinate above the baseline the font extends; descent
// is the coordinate below the baseline the font extends (i.e. it is typically negative)
// lineGap is the spacing between one row's descent and the next row's ascent...
// so you should advance the vertical position by "*ascent - *descent + *lineGap"
//   these are expressed in unscaled coordinates, so you must multiply by
//   the scale factor for a given size

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STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1);
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// the bounding box around all possible characters

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STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing);
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// leftSideBearing is the offset from the current horizontal position to the left edge of the character
// advanceWidth is the offset from the current horizontal position to the next horizontal position
//   these are expressed in unscaled coordinates

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STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2);
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// an additional amount to add to the 'advance' value between ch1 and ch2

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STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1);
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// Gets the bounding box of the visible part of the glyph, in unscaled coordinates

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STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing);
STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2);
STBTT_DEF int  stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
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// as above, but takes one or more glyph indices for greater efficiency


//////////////////////////////////////////////////////////////////////////////
//
// GLYPH SHAPES (you probably don't need these, but they have to go before
// the bitmaps for C declaration-order reasons)
//

#ifndef STBTT_vmove // you can predefine these to use different values (but why?)
   enum {
      STBTT_vmove=1,
      STBTT_vline,
      STBTT_vcurve
   };
#endif

#ifndef stbtt_vertex // you can predefine this to use different values
                   // (we share this with other code at RAD)
   #define stbtt_vertex_type short // can't use stbtt_int16 because that's not visible in the header file
   typedef struct
   {
      stbtt_vertex_type x,y,cx,cy;
      unsigned char type,padding;
   } stbtt_vertex;
#endif

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STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index);
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// returns non-zero if nothing is drawn for this glyph

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STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices);
STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **vertices);
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// returns # of vertices and fills *vertices with the pointer to them
//   these are expressed in "unscaled" coordinates
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//
// The shape is a series of countours. Each one starts with
// a STBTT_moveto, then consists of a series of mixed
// STBTT_lineto and STBTT_curveto segments. A lineto
// draws a line from previous endpoint to its x,y; a curveto
// draws a quadratic bezier from previous endpoint to
// its x,y, using cx,cy as the bezier control point.
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STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices);
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// frees the data allocated above

//////////////////////////////////////////////////////////////////////////////
//
// BITMAP RENDERING
//

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STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata);
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// frees the bitmap allocated below

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STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
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// allocates a large-enough single-channel 8bpp bitmap and renders the
// specified character/glyph at the specified scale into it, with
// antialiasing. 0 is no coverage (transparent), 255 is fully covered (opaque).
// *width & *height are filled out with the width & height of the bitmap,
// which is stored left-to-right, top-to-bottom.
//
// xoff/yoff are the offset it pixel space from the glyph origin to the top-left of the bitmap

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STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
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// the same as stbtt_GetCodepoitnBitmap, but you can specify a subpixel
// shift for the character

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STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint);
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// the same as stbtt_GetCodepointBitmap, but you pass in storage for the bitmap
// in the form of 'output', with row spacing of 'out_stride' bytes. the bitmap
// is clipped to out_w/out_h bytes. Call stbtt_GetCodepointBitmapBox to get the
// width and height and positioning info for it first.

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STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint);
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// same as stbtt_MakeCodepointBitmap, but you can specify a subpixel
// shift for the character

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STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
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// get the bbox of the bitmap centered around the glyph origin; so the
// bitmap width is ix1-ix0, height is iy1-iy0, and location to place
// the bitmap top left is (leftSideBearing*scale,iy0).
// (Note that the bitmap uses y-increases-down, but the shape uses
// y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.)

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STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);
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// same as stbtt_GetCodepointBitmapBox, but you can specify a subpixel
// shift for the character

// the following functions are equivalent to the above functions, but operate
// on glyph indices instead of Unicode codepoints (for efficiency)
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STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff);
STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff);
STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph);
STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph);
STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);
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// @TODO: don't expose this structure
typedef struct
{
   int w,h,stride;
   unsigned char *pixels;
} stbtt__bitmap;

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// rasterize a shape with quadratic beziers into a bitmap
STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result,        // 1-channel bitmap to draw into
                               float flatness_in_pixels,     // allowable error of curve in pixels
                               stbtt_vertex *vertices,       // array of vertices defining shape
                               int num_verts,                // number of vertices in above array
                               float scale_x, float scale_y, // scale applied to input vertices
                               float shift_x, float shift_y, // translation applied to input vertices
                               int x_off, int y_off,         // another translation applied to input
                               int invert,                   // if non-zero, vertically flip shape
                               void *userdata);              // context for to STBTT_MALLOC
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//////////////////////////////////////////////////////////////////////////////
//
// Finding the right font...
//
// You should really just solve this offline, keep your own tables
// of what font is what, and don't try to get it out of the .ttf file.
// That's because getting it out of the .ttf file is really hard, because
// the names in the file can appear in many possible encodings, in many
// possible languages, and e.g. if you need a case-insensitive comparison,
// the details of that depend on the encoding & language in a complex way
// (actually underspecified in truetype, but also gigantic).
//
// But you can use the provided functions in two possible ways:
//     stbtt_FindMatchingFont() will use *case-sensitive* comparisons on
//             unicode-encoded names to try to find the font you want;
//             you can run this before calling stbtt_InitFont()
//
//     stbtt_GetFontNameString() lets you get any of the various strings
//             from the file yourself and do your own comparisons on them.
//             You have to have called stbtt_InitFont() first.


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STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags);
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// returns the offset (not index) of the font that matches, or -1 if none
//   if you use STBTT_MACSTYLE_DONTCARE, use a font name like "Arial Bold".
//   if you use any other flag, use a font name like "Arial"; this checks
//     the 'macStyle' header field; i don't know if fonts set this consistently
#define STBTT_MACSTYLE_DONTCARE     0
#define STBTT_MACSTYLE_BOLD         1
#define STBTT_MACSTYLE_ITALIC       2
#define STBTT_MACSTYLE_UNDERSCORE   4
#define STBTT_MACSTYLE_NONE         8   // <= not same as 0, this makes us check the bitfield is 0

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STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2);
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// returns 1/0 whether the first string interpreted as utf8 is identical to
// the second string interpreted as big-endian utf16... useful for strings from next func

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STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID);
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// returns the string (which may be big-endian double byte, e.g. for unicode)
// and puts the length in bytes in *length.
//
// some of the values for the IDs are below; for more see the truetype spec:
//     http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6name.html
//     http://www.microsoft.com/typography/otspec/name.htm

enum { // platformID
   STBTT_PLATFORM_ID_UNICODE   =0,
   STBTT_PLATFORM_ID_MAC       =1,
   STBTT_PLATFORM_ID_ISO       =2,
   STBTT_PLATFORM_ID_MICROSOFT =3
};

enum { // encodingID for STBTT_PLATFORM_ID_UNICODE
   STBTT_UNICODE_EID_UNICODE_1_0    =0,
   STBTT_UNICODE_EID_UNICODE_1_1    =1,
   STBTT_UNICODE_EID_ISO_10646      =2,
   STBTT_UNICODE_EID_UNICODE_2_0_BMP=3,
   STBTT_UNICODE_EID_UNICODE_2_0_FULL=4
};

enum { // encodingID for STBTT_PLATFORM_ID_MICROSOFT
   STBTT_MS_EID_SYMBOL        =0,
   STBTT_MS_EID_UNICODE_BMP   =1,
   STBTT_MS_EID_SHIFTJIS      =2,
   STBTT_MS_EID_UNICODE_FULL  =10
};

enum { // encodingID for STBTT_PLATFORM_ID_MAC; same as Script Manager codes
   STBTT_MAC_EID_ROMAN        =0,   STBTT_MAC_EID_ARABIC       =4,
   STBTT_MAC_EID_JAPANESE     =1,   STBTT_MAC_EID_HEBREW       =5,
   STBTT_MAC_EID_CHINESE_TRAD =2,   STBTT_MAC_EID_GREEK        =6,
   STBTT_MAC_EID_KOREAN       =3,   STBTT_MAC_EID_RUSSIAN      =7
};

enum { // languageID for STBTT_PLATFORM_ID_MICROSOFT; same as LCID...
       // problematic because there are e.g. 16 english LCIDs and 16 arabic LCIDs
   STBTT_MS_LANG_ENGLISH     =0x0409,   STBTT_MS_LANG_ITALIAN     =0x0410,
   STBTT_MS_LANG_CHINESE     =0x0804,   STBTT_MS_LANG_JAPANESE    =0x0411,
   STBTT_MS_LANG_DUTCH       =0x0413,   STBTT_MS_LANG_KOREAN      =0x0412,
   STBTT_MS_LANG_FRENCH      =0x040c,   STBTT_MS_LANG_RUSSIAN     =0x0419,
   STBTT_MS_LANG_GERMAN      =0x0407,   STBTT_MS_LANG_SPANISH     =0x0409,
   STBTT_MS_LANG_HEBREW      =0x040d,   STBTT_MS_LANG_SWEDISH     =0x041D
};

enum { // languageID for STBTT_PLATFORM_ID_MAC
   STBTT_MAC_LANG_ENGLISH      =0 ,   STBTT_MAC_LANG_JAPANESE     =11,
   STBTT_MAC_LANG_ARABIC       =12,   STBTT_MAC_LANG_KOREAN       =23,
   STBTT_MAC_LANG_DUTCH        =4 ,   STBTT_MAC_LANG_RUSSIAN      =32,
   STBTT_MAC_LANG_FRENCH       =1 ,   STBTT_MAC_LANG_SPANISH      =6 ,
   STBTT_MAC_LANG_GERMAN       =2 ,   STBTT_MAC_LANG_SWEDISH      =5 ,
   STBTT_MAC_LANG_HEBREW       =10,   STBTT_MAC_LANG_CHINESE_SIMPLIFIED =33,
   STBTT_MAC_LANG_ITALIAN      =3 ,   STBTT_MAC_LANG_CHINESE_TRAD =19
};

#ifdef __cplusplus
}
#endif

#endif // __STB_INCLUDE_STB_TRUETYPE_H__

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
////
////   IMPLEMENTATION
////
////

#ifdef STB_TRUETYPE_IMPLEMENTATION

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#ifndef STBTT_MAX_OVERSAMPLE
#define STBTT_MAX_OVERSAMPLE   8
#endif

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#if STBTT_MAX_OVERSAMPLE > 255
#error "STBTT_MAX_OVERSAMPLE cannot be > 255"
#endif

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typedef int stbtt__test_oversample_pow2[(STBTT_MAX_OVERSAMPLE & (STBTT_MAX_OVERSAMPLE-1)) == 0 ? 1 : -1];
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#ifndef STBTT_RASTERIZER_VERSION
#define STBTT_RASTERIZER_VERSION 2
#endif

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#ifdef _MSC_VER
#define STBTT__NOTUSED(v)  (void)(v)
#else
#define STBTT__NOTUSED(v)  (void)sizeof(v)
#endif

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//////////////////////////////////////////////////////////////////////////
//
// accessors to parse data from file
//

// on platforms that don't allow misaligned reads, if we want to allow
// truetype fonts that aren't padded to alignment, define ALLOW_UNALIGNED_TRUETYPE

#define ttBYTE(p)     (* (stbtt_uint8 *) (p))
#define ttCHAR(p)     (* (stbtt_int8 *) (p))
#define ttFixed(p)    ttLONG(p)

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static stbtt_uint16 ttUSHORT(stbtt_uint8 *p) { return p[0]*256 + p[1]; }
static stbtt_int16 ttSHORT(stbtt_uint8 *p)   { return p[0]*256 + p[1]; }
static stbtt_uint32 ttULONG(stbtt_uint8 *p)  { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
static stbtt_int32 ttLONG(stbtt_uint8 *p)    { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
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#define stbtt_tag4(p,c0,c1,c2,c3) ((p)[0] == (c0) && (p)[1] == (c1) && (p)[2] == (c2) && (p)[3] == (c3))
#define stbtt_tag(p,str)           stbtt_tag4(p,str[0],str[1],str[2],str[3])

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static int stbtt__isfont(stbtt_uint8 *font)
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{
   // check the version number
   if (stbtt_tag4(font, '1',0,0,0))  return 1; // TrueType 1
   if (stbtt_tag(font, "typ1"))   return 1; // TrueType with type 1 font -- we don't support this!
   if (stbtt_tag(font, "OTTO"))   return 1; // OpenType with CFF
   if (stbtt_tag4(font, 0,1,0,0)) return 1; // OpenType 1.0
   return 0;
}

// @OPTIMIZE: binary search
static stbtt_uint32 stbtt__find_table(stbtt_uint8 *data, stbtt_uint32 fontstart, const char *tag)
{
   stbtt_int32 num_tables = ttUSHORT(data+fontstart+4);
   stbtt_uint32 tabledir = fontstart + 12;
   stbtt_int32 i;
   for (i=0; i < num_tables; ++i) {
      stbtt_uint32 loc = tabledir + 16*i;
      if (stbtt_tag(data+loc+0, tag))
         return ttULONG(data+loc+8);
   }
   return 0;
}

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static int stbtt_GetFontOffsetForIndex_internal(unsigned char *font_collection, int index)
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{
   // if it's just a font, there's only one valid index
   if (stbtt__isfont(font_collection))
      return index == 0 ? 0 : -1;

   // check if it's a TTC
   if (stbtt_tag(font_collection, "ttcf")) {
      // version 1?
      if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) {
         stbtt_int32 n = ttLONG(font_collection+8);
         if (index >= n)
            return -1;
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         return ttULONG(font_collection+12+index*4);
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      }
   }
   return -1;
}

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static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, int fontstart)
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{
   stbtt_uint32 cmap, t;
   stbtt_int32 i,numTables;

   info->data = data;
   info->fontstart = fontstart;

   cmap = stbtt__find_table(data, fontstart, "cmap");       // required
   info->loca = stbtt__find_table(data, fontstart, "loca"); // required
   info->head = stbtt__find_table(data, fontstart, "head"); // required
   info->glyf = stbtt__find_table(data, fontstart, "glyf"); // required
   info->hhea = stbtt__find_table(data, fontstart, "hhea"); // required
   info->hmtx = stbtt__find_table(data, fontstart, "hmtx"); // required
   info->kern = stbtt__find_table(data, fontstart, "kern"); // not required
   if (!cmap || !info->loca || !info->head || !info->glyf || !info->hhea || !info->hmtx)
      return 0;

   t = stbtt__find_table(data, fontstart, "maxp");
   if (t)
      info->numGlyphs = ttUSHORT(data+t+4);
   else
      info->numGlyphs = 0xffff;

   // find a cmap encoding table we understand *now* to avoid searching
   // later. (todo: could make this installable)
   // the same regardless of glyph.
   numTables = ttUSHORT(data + cmap + 2);
   info->index_map = 0;
   for (i=0; i < numTables; ++i) {
      stbtt_uint32 encoding_record = cmap + 4 + 8 * i;
      // find an encoding we understand:
      switch(ttUSHORT(data+encoding_record)) {
         case STBTT_PLATFORM_ID_MICROSOFT:
            switch (ttUSHORT(data+encoding_record+2)) {
               case STBTT_MS_EID_UNICODE_BMP:
               case STBTT_MS_EID_UNICODE_FULL:
                  // MS/Unicode
                  info->index_map = cmap + ttULONG(data+encoding_record+4);
                  break;
            }
            break;
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        case STBTT_PLATFORM_ID_UNICODE:
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            // Mac/iOS has these
            // all the encodingIDs are unicode, so we don't bother to check it
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            info->index_map = cmap + ttULONG(data+encoding_record+4);
            break;
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      }
   }
   if (info->index_map == 0)
      return 0;

   info->indexToLocFormat = ttUSHORT(data+info->head + 50);
   return 1;
}

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STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint)
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{
   stbtt_uint8 *data = info->data;
   stbtt_uint32 index_map = info->index_map;

   stbtt_uint16 format = ttUSHORT(data + index_map + 0);
   if (format == 0) { // apple byte encoding
      stbtt_int32 bytes = ttUSHORT(data + index_map + 2);
      if (unicode_codepoint < bytes-6)
         return ttBYTE(data + index_map + 6 + unicode_codepoint);
      return 0;
   } else if (format == 6) {
      stbtt_uint32 first = ttUSHORT(data + index_map + 6);
      stbtt_uint32 count = ttUSHORT(data + index_map + 8);
      if ((stbtt_uint32) unicode_codepoint >= first && (stbtt_uint32) unicode_codepoint < first+count)
         return ttUSHORT(data + index_map + 10 + (unicode_codepoint - first)*2);
      return 0;
   } else if (format == 2) {
      STBTT_assert(0); // @TODO: high-byte mapping for japanese/chinese/korean
      return 0;
   } else if (format == 4) { // standard mapping for windows fonts: binary search collection of ranges
      stbtt_uint16 segcount = ttUSHORT(data+index_map+6) >> 1;
      stbtt_uint16 searchRange = ttUSHORT(data+index_map+8) >> 1;
      stbtt_uint16 entrySelector = ttUSHORT(data+index_map+10);
      stbtt_uint16 rangeShift = ttUSHORT(data+index_map+12) >> 1;

      // do a binary search of the segments
      stbtt_uint32 endCount = index_map + 14;
      stbtt_uint32 search = endCount;

      if (unicode_codepoint > 0xffff)
         return 0;

      // they lie from endCount .. endCount + segCount
      // but searchRange is the nearest power of two, so...
      if (unicode_codepoint >= ttUSHORT(data + search + rangeShift*2))
         search += rangeShift*2;

      // now decrement to bias correctly to find smallest
      search -= 2;
      while (entrySelector) {
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         stbtt_uint16 end;
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         searchRange >>= 1;
         end = ttUSHORT(data + search + searchRange*2);
         if (unicode_codepoint > end)
            search += searchRange*2;
         --entrySelector;
      }
      search += 2;

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      {
         stbtt_uint16 offset, start;
         stbtt_uint16 item = (stbtt_uint16) ((search - endCount) >> 1);
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         STBTT_assert(unicode_codepoint <= ttUSHORT(data + endCount + 2*item));
         start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item);
         if (unicode_codepoint < start)
            return 0;
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         offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item);
         if (offset == 0)
            return (stbtt_uint16) (unicode_codepoint + ttSHORT(data + index_map + 14 + segcount*4 + 2 + 2*item));
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         return ttUSHORT(data + offset + (unicode_codepoint-start)*2 + index_map + 14 + segcount*6 + 2 + 2*item);
      }
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   } else if (format == 12 || format == 13) {
      stbtt_uint32 ngroups = ttULONG(data+index_map+12);
      stbtt_int32 low,high;
      low = 0; high = (stbtt_int32)ngroups;
      // Binary search the right group.
      while (low < high) {
         stbtt_int32 mid = low + ((high-low) >> 1); // rounds down, so low <= mid < high
         stbtt_uint32 start_char = ttULONG(data+index_map+16+mid*12);
         stbtt_uint32 end_char = ttULONG(data+index_map+16+mid*12+4);
         if ((stbtt_uint32) unicode_codepoint < start_char)
            high = mid;
         else if ((stbtt_uint32) unicode_codepoint > end_char)
            low = mid+1;
         else {
            stbtt_uint32 start_glyph = ttULONG(data+index_map+16+mid*12+8);
            if (format == 12)
               return start_glyph + unicode_codepoint-start_char;
            else // format == 13
               return start_glyph;
         }
      }
      return 0; // not found
   }
   // @TODO
   STBTT_assert(0);
   return 0;
}

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STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices)
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{
   return stbtt_GetGlyphShape(info, stbtt_FindGlyphIndex(info, unicode_codepoint), vertices);
}

static void stbtt_setvertex(stbtt_vertex *v, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy)
{
   v->type = type;
   v->x = (stbtt_int16) x;
   v->y = (stbtt_int16) y;
   v->cx = (stbtt_int16) cx;
   v->cy = (stbtt_int16) cy;
}

static int stbtt__GetGlyfOffset(const stbtt_fontinfo *info, int glyph_index)
{
   int g1,g2;

   if (glyph_index >= info->numGlyphs) return -1; // glyph index out of range
   if (info->indexToLocFormat >= 2)    return -1; // unknown index->glyph map format

   if (info->indexToLocFormat == 0) {
      g1 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2) * 2;
      g2 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2 + 2) * 2;
   } else {
      g1 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4);
      g2 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4 + 4);
   }

   return g1==g2 ? -1 : g1; // if length is 0, return -1
}

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STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
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{
   int g = stbtt__GetGlyfOffset(info, glyph_index);
   if (g < 0) return 0;

   if (x0) *x0 = ttSHORT(info->data + g + 2);
   if (y0) *y0 = ttSHORT(info->data + g + 4);
   if (x1) *x1 = ttSHORT(info->data + g + 6);
   if (y1) *y1 = ttSHORT(info->data + g + 8);
   return 1;
}

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STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1)
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{
   return stbtt_GetGlyphBox(info, stbtt_FindGlyphIndex(info,codepoint), x0,y0,x1,y1);
}

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STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index)
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{
   stbtt_int16 numberOfContours;
   int g = stbtt__GetGlyfOffset(info, glyph_index);
   if (g < 0) return 1;
   numberOfContours = ttSHORT(info->data + g);
   return numberOfContours == 0;
}

static int stbtt__close_shape(stbtt_vertex *vertices, int num_vertices, int was_off, int start_off,
    stbtt_int32 sx, stbtt_int32 sy, stbtt_int32 scx, stbtt_int32 scy, stbtt_int32 cx, stbtt_int32 cy)
{
   if (start_off) {
      if (was_off)
         stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+scx)>>1, (cy+scy)>>1, cx,cy);
      stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, sx,sy,scx,scy);
   } else {
      if (was_off)
         stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve,sx,sy,cx,cy);
      else
         stbtt_setvertex(&vertices[num_vertices++], STBTT_vline,sx,sy,0,0);
   }
   return num_vertices;
}

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STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
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{
   stbtt_int16 numberOfContours;
   stbtt_uint8 *endPtsOfContours;
   stbtt_uint8 *data = info->data;
   stbtt_vertex *vertices=0;
   int num_vertices=0;
   int g = stbtt__GetGlyfOffset(info, glyph_index);

   *pvertices = NULL;

   if (g < 0) return 0;

   numberOfContours = ttSHORT(data + g);

   if (numberOfContours > 0) {
      stbtt_uint8 flags=0,flagcount;
      stbtt_int32 ins, i,j=0,m,n, next_move, was_off=0, off, start_off=0;
      stbtt_int32 x,y,cx,cy,sx,sy, scx,scy;
      stbtt_uint8 *points;
      endPtsOfContours = (data + g + 10);
      ins = ttUSHORT(data + g + 10 + numberOfContours * 2);
      points = data + g + 10 + numberOfContours * 2 + 2 + ins;

      n = 1+ttUSHORT(endPtsOfContours + numberOfContours*2-2);

      m = n + 2*numberOfContours;  // a loose bound on how many vertices we might need
      vertices = (stbtt_vertex *) STBTT_malloc(m * sizeof(vertices[0]), info->userdata);
      if (vertices == 0)
         return 0;

      next_move = 0;
      flagcount=0;

      // in first pass, we load uninterpreted data into the allocated array
      // above, shifted to the end of the array so we won't overwrite it when
      // we create our final data starting from the front

      off = m - n; // starting offset for uninterpreted data, regardless of how m ends up being calculated

      // first load flags

      for (i=0; i < n; ++i) {
         if (flagcount == 0) {
            flags = *points++;
            if (flags & 8)
               flagcount = *points++;
         } else
            --flagcount;
         vertices[off+i].type = flags;
      }

      // now load x coordinates
      x=0;
      for (i=0; i < n; ++i) {
         flags = vertices[off+i].type;
         if (flags & 2) {
            stbtt_int16 dx = *points++;
            x += (flags & 16) ? dx : -dx; // ???
         } else {
            if (!(flags & 16)) {
               x = x + (stbtt_int16) (points[0]*256 + points[1]);
               points += 2;
            }
         }
         vertices[off+i].x = (stbtt_int16) x;
      }

      // now load y coordinates
      y=0;
      for (i=0; i < n; ++i) {
         flags = vertices[off+i].type;
         if (flags & 4) {
            stbtt_int16 dy = *points++;
            y += (flags & 32) ? dy : -dy; // ???
         } else {
            if (!(flags & 32)) {
               y = y + (stbtt_int16) (points[0]*256 + points[1]);
               points += 2;
            }
         }
         vertices[off+i].y = (stbtt_int16) y;
      }

      // now convert them to our format
      num_vertices=0;
      sx = sy = cx = cy = scx = scy = 0;
      for (i=0; i < n; ++i) {
         flags = vertices[off+i].type;
         x     = (stbtt_int16) vertices[off+i].x;
         y     = (stbtt_int16) vertices[off+i].y;

         if (next_move == i) {
            if (i != 0)
               num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy);

            // now start the new one               
            start_off = !(flags & 1);
            if (start_off) {
               // if we start off with an off-curve point, then when we need to find a point on the curve
               // where we can start, and we need to save some state for when we wraparound.
               scx = x;
               scy = y;
               if (!(vertices[off+i+1].type & 1)) {
                  // next point is also a curve point, so interpolate an on-point curve
                  sx = (x + (stbtt_int32) vertices[off+i+1].x) >> 1;
                  sy = (y + (stbtt_int32) vertices[off+i+1].y) >> 1;
               } else {
                  // otherwise just use the next point as our start point
                  sx = (stbtt_int32) vertices[off+i+1].x;
                  sy = (stbtt_int32) vertices[off+i+1].y;
                  ++i; // we're using point i+1 as the starting point, so skip it
               }
            } else {
               sx = x;
               sy = y;
            }
            stbtt_setvertex(&vertices[num_vertices++], STBTT_vmove,sx,sy,0,0);
            was_off = 0;
            next_move = 1 + ttUSHORT(endPtsOfContours+j*2);
            ++j;
         } else {
            if (!(flags & 1)) { // if it's a curve
               if (was_off) // two off-curve control points in a row means interpolate an on-curve midpoint
                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+x)>>1, (cy+y)>>1, cx, cy);
               cx = x;
               cy = y;
               was_off = 1;
            } else {
               if (was_off)
                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, x,y, cx, cy);
               else
                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vline, x,y,0,0);
               was_off = 0;
            }
         }
      }
      num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy);
   } else if (numberOfContours == -1) {
      // Compound shapes.
      int more = 1;
      stbtt_uint8 *comp = data + g + 10;
      num_vertices = 0;
      vertices = 0;
      while (more) {
         stbtt_uint16 flags, gidx;
         int comp_num_verts = 0, i;
         stbtt_vertex *comp_verts = 0, *tmp = 0;
         float mtx[6] = {1,0,0,1,0,0}, m, n;
         
         flags = ttSHORT(comp); comp+=2;
         gidx = ttSHORT(comp); comp+=2;

         if (flags & 2) { // XY values
            if (flags & 1) { // shorts
               mtx[4] = ttSHORT(comp); comp+=2;
               mtx[5] = ttSHORT(comp); comp+=2;
            } else {
               mtx[4] = ttCHAR(comp); comp+=1;
               mtx[5] = ttCHAR(comp); comp+=1;
            }
         }
         else {
            // @TODO handle matching point
            STBTT_assert(0);
         }
         if (flags & (1<<3)) { // WE_HAVE_A_SCALE
            mtx[0] = mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
            mtx[1] = mtx[2] = 0;
         } else if (flags & (1<<6)) { // WE_HAVE_AN_X_AND_YSCALE
            mtx[0] = ttSHORT(comp)/16384.0f; comp+=2;
            mtx[1] = mtx[2] = 0;
            mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
         } else if (flags & (1<<7)) { // WE_HAVE_A_TWO_BY_TWO
            mtx[0] = ttSHORT(comp)/16384.0f; comp+=2;
            mtx[1] = ttSHORT(comp)/16384.0f; comp+=2;
            mtx[2] = ttSHORT(comp)/16384.0f; comp+=2;
            mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
         }
         
         // Find transformation scales.
1421 1422
         m = (float) STBTT_sqrt(mtx[0]*mtx[0] + mtx[1]*mtx[1]);
         n = (float) STBTT_sqrt(mtx[2]*mtx[2] + mtx[3]*mtx[3]);
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         // Get indexed glyph.
         comp_num_verts = stbtt_GetGlyphShape(info, gidx, &comp_verts);
         if (comp_num_verts > 0) {
            // Transform vertices.
            for (i = 0; i < comp_num_verts; ++i) {
               stbtt_vertex* v = &comp_verts[i];
               stbtt_vertex_type x,y;
               x=v->x; y=v->y;
               v->x = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4]));
               v->y = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5]));
               x=v->cx; y=v->cy;
               v->cx = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4]));
               v->cy = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5]));
            }
            // Append vertices.
            tmp = (stbtt_vertex*)STBTT_malloc((num_vertices+comp_num_verts)*sizeof(stbtt_vertex), info->userdata);
            if (!tmp) {
               if (vertices) STBTT_free(vertices, info->userdata);
               if (comp_verts) STBTT_free(comp_verts, info->userdata);
               return 0;
            }
1445 1446
            if (num_vertices > 0) STBTT_memcpy(tmp, vertices, num_vertices*sizeof(stbtt_vertex));
            STBTT_memcpy(tmp+num_vertices, comp_verts, comp_num_verts*sizeof(stbtt_vertex));
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            if (vertices) STBTT_free(vertices, info->userdata);
            vertices = tmp;
            STBTT_free(comp_verts, info->userdata);
            num_vertices += comp_num_verts;
         }
         // More components ?
         more = flags & (1<<5);
      }
   } else if (numberOfContours < 0) {
      // @TODO other compound variations?
      STBTT_assert(0);
   } else {
      // numberOfCounters == 0, do nothing
   }

   *pvertices = vertices;
   return num_vertices;
}

1466
STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing)
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{
   stbtt_uint16 numOfLongHorMetrics = ttUSHORT(info->data+info->hhea + 34);
   if (glyph_index < numOfLongHorMetrics) {
      if (advanceWidth)     *advanceWidth    = ttSHORT(info->data + info->hmtx + 4*glyph_index);
      if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*glyph_index + 2);
   } else {
      if (advanceWidth)     *advanceWidth    = ttSHORT(info->data + info->hmtx + 4*(numOfLongHorMetrics-1));
      if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*numOfLongHorMetrics + 2*(glyph_index - numOfLongHorMetrics));
   }
}

1478
STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2)
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{
   stbtt_uint8 *data = info->data + info->kern;
   stbtt_uint32 needle, straw;
   int l, r, m;

   // we only look at the first table. it must be 'horizontal' and format 0.
   if (!info->kern)
      return 0;
   if (ttUSHORT(data+2) < 1) // number of tables, need at least 1
      return 0;
   if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format
      return 0;

   l = 0;
   r = ttUSHORT(data+10) - 1;
   needle = glyph1 << 16 | glyph2;
   while (l <= r) {
      m = (l + r) >> 1;
      straw = ttULONG(data+18+(m*6)); // note: unaligned read
      if (needle < straw)
         r = m - 1;
      else if (needle > straw)
         l = m + 1;
      else
         return ttSHORT(data+22+(m*6));
   }
   return 0;
}

1508
STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2)
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{
   if (!info->kern) // if no kerning table, don't waste time looking up both codepoint->glyphs
      return 0;
   return stbtt_GetGlyphKernAdvance(info, stbtt_FindGlyphIndex(info,ch1), stbtt_FindGlyphIndex(info,ch2));
}

1515
STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing)
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{
   stbtt_GetGlyphHMetrics(info, stbtt_FindGlyphIndex(info,codepoint), advanceWidth, leftSideBearing);
}

1520
STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap)
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{
   if (ascent ) *ascent  = ttSHORT(info->data+info->hhea + 4);
   if (descent) *descent = ttSHORT(info->data+info->hhea + 6);
   if (lineGap) *lineGap = ttSHORT(info->data+info->hhea + 8);
}

1527
STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1)
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{
   *x0 = ttSHORT(info->data + info->head + 36);
   *y0 = ttSHORT(info->data + info->head + 38);
   *x1 = ttSHORT(info->data + info->head + 40);
   *y1 = ttSHORT(info->data + info->head + 42);
}

1535
STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float height)
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{
   int fheight = ttSHORT(info->data + info->hhea + 4) - ttSHORT(info->data + info->hhea + 6);
   return (float) height / fheight;
}

1541
STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels)
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{
   int unitsPerEm = ttUSHORT(info->data + info->head + 18);
   return pixels / unitsPerEm;
}

1547
STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *v)
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{
   STBTT_free(v, info->userdata);
}

//////////////////////////////////////////////////////////////////////////////
//
// antialiasing software rasterizer
//

1557
STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
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{
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   int x0=0,y0=0,x1,y1; // =0 suppresses compiler warning
1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572
   if (!stbtt_GetGlyphBox(font, glyph, &x0,&y0,&x1,&y1)) {
      // e.g. space character
      if (ix0) *ix0 = 0;
      if (iy0) *iy0 = 0;
      if (ix1) *ix1 = 0;
      if (iy1) *iy1 = 0;
   } else {
      // move to integral bboxes (treating pixels as little squares, what pixels get touched)?
      if (ix0) *ix0 = STBTT_ifloor( x0 * scale_x + shift_x);
      if (iy0) *iy0 = STBTT_ifloor(-y1 * scale_y + shift_y);
      if (ix1) *ix1 = STBTT_iceil ( x1 * scale_x + shift_x);
      if (iy1) *iy1 = STBTT_iceil (-y0 * scale_y + shift_y);
   }
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}
1574

1575
STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
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{
   stbtt_GetGlyphBitmapBoxSubpixel(font, glyph, scale_x, scale_y,0.0f,0.0f, ix0, iy0, ix1, iy1);
}

1580
STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
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{
   stbtt_GetGlyphBitmapBoxSubpixel(font, stbtt_FindGlyphIndex(font,codepoint), scale_x, scale_y,shift_x,shift_y, ix0,iy0,ix1,iy1);
}

1585
STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
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{
   stbtt_GetCodepointBitmapBoxSubpixel(font, codepoint, scale_x, scale_y,0.0f,0.0f, ix0,iy0,ix1,iy1);
}

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//////////////////////////////////////////////////////////////////////////////
//
//  Rasterizer

typedef struct stbtt__hheap_chunk
{
   struct stbtt__hheap_chunk *next;
} stbtt__hheap_chunk;

typedef struct stbtt__hheap
{
   struct stbtt__hheap_chunk *head;
   void   *first_free;
   int    num_remaining_in_head_chunk;
} stbtt__hheap;

static void *stbtt__hheap_alloc(stbtt__hheap *hh, size_t size, void *userdata)
{
   if (hh->first_free) {
      void *p = hh->first_free;
      hh->first_free = * (void **) p;
      return p;
   } else {
      if (hh->num_remaining_in_head_chunk == 0) {
         int count = (size < 32 ? 2000 : size < 128 ? 800 : 100);
         stbtt__hheap_chunk *c = (stbtt__hheap_chunk *) STBTT_malloc(sizeof(stbtt__hheap_chunk) + size * count, userdata);
         if (c == NULL)
            return NULL;
         c->next = hh->head;
         hh->head = c;
         hh->num_remaining_in_head_chunk = count;
      }
      --hh->num_remaining_in_head_chunk;
      return (char *) (hh->head) + size * hh->num_remaining_in_head_chunk;
   }
}

static void stbtt__hheap_free(stbtt__hheap *hh, void *p)
{
   *(void **) p = hh->first_free;
   hh->first_free = p;
}

static void stbtt__hheap_cleanup(stbtt__hheap *hh, void *userdata)
{
   stbtt__hheap_chunk *c = hh->head;
   while (c) {
      stbtt__hheap_chunk *n = c->next;
      STBTT_free(c, userdata);
      c = n;
   }
}

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typedef struct stbtt__edge {
   float x0,y0, x1,y1;
   int invert;
} stbtt__edge;

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typedef struct stbtt__active_edge
{
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   struct stbtt__active_edge *next;
   #if STBTT_RASTERIZER_VERSION==1
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   int x,dx;
   float ey;
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   int direction;
   #elif STBTT_RASTERIZER_VERSION==2
   float fx,fdx,fdy;
   float direction;
   float sy;
   float ey;
   #else
   #error "Unrecognized value of STBTT_RASTERIZER_VERSION"
   #endif
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} stbtt__active_edge;

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#if STBTT_RASTERIZER_VERSION == 1
#define STBTT_FIXSHIFT   10
#define STBTT_FIX        (1 << STBTT_FIXSHIFT)
#define STBTT_FIXMASK    (STBTT_FIX-1)
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static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
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{
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   stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata);
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   float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
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   STBTT_assert(z != NULL);
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   if (!z) return z;
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   // round dx down to avoid overshooting
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   if (dxdy < 0)
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      z->dx = -STBTT_ifloor(STBTT_FIX * -dxdy);
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   else
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      z->dx = STBTT_ifloor(STBTT_FIX * dxdy);

   z->x = STBTT_ifloor(STBTT_FIX * e->x0 + z->dx * (start_point - e->y0)); // use z->dx so when we offset later it's by the same amount
   z->x -= off_x * STBTT_FIX;

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   z->ey = e->y1;
   z->next = 0;
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   z->direction = e->invert ? 1 : -1;
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   return z;
}
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#elif STBTT_RASTERIZER_VERSION == 2
static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
{
   stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata);
   float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
1697
   STBTT_assert(z != NULL);
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   //STBTT_assert(e->y0 <= start_point);
   if (!z) return z;
   z->fdx = dxdy;
1701
   z->fdy = dxdy != 0.0f ? (1.0f/dxdy) : 0.0f;
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   z->fx = e->x0 + dxdy * (start_point - e->y0);
   z->fx -= off_x;
   z->direction = e->invert ? 1.0f : -1.0f;
   z->sy = e->y0;
   z->ey = e->y1;
   z->next = 0;
   return z;
}
#else
#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
#endif
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#if STBTT_RASTERIZER_VERSION == 1
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// note: this routine clips fills that extend off the edges... ideally this
// wouldn't happen, but it could happen if the truetype glyph bounding boxes
// are wrong, or if the user supplies a too-small bitmap
static void stbtt__fill_active_edges(unsigned char *scanline, int len, stbtt__active_edge *e, int max_weight)
{
   // non-zero winding fill
   int x0=0, w=0;

   while (e) {
      if (w == 0) {
         // if we're currently at zero, we need to record the edge start point
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         x0 = e->x; w += e->direction;
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      } else {
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         int x1 = e->x; w += e->direction;
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         // if we went to zero, we need to draw
         if (w == 0) {
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            int i = x0 >> STBTT_FIXSHIFT;
            int j = x1 >> STBTT_FIXSHIFT;
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            if (i < len && j >= 0) {
               if (i == j) {
                  // x0,x1 are the same pixel, so compute combined coverage
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                  scanline[i] = scanline[i] + (stbtt_uint8) ((x1 - x0) * max_weight >> STBTT_FIXSHIFT);
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               } else {
                  if (i >= 0) // add antialiasing for x0
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                     scanline[i] = scanline[i] + (stbtt_uint8) (((STBTT_FIX - (x0 & STBTT_FIXMASK)) * max_weight) >> STBTT_FIXSHIFT);
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                  else
                     i = -1; // clip

                  if (j < len) // add antialiasing for x1
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                     scanline[j] = scanline[j] + (stbtt_uint8) (((x1 & STBTT_FIXMASK) * max_weight) >> STBTT_FIXSHIFT);
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                  else
                     j = len; // clip

                  for (++i; i < j; ++i) // fill pixels between x0 and x1
                     scanline[i] = scanline[i] + (stbtt_uint8) max_weight;
               }
            }
         }
      }
      
      e = e->next;
   }
}

static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
{
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   stbtt__hheap hh = { 0, 0, 0 };
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   stbtt__active_edge *active = NULL;
   int y,j=0;
   int max_weight = (255 / vsubsample);  // weight per vertical scanline
   int s; // vertical subsample index
   unsigned char scanline_data[512], *scanline;

   if (result->w > 512)
      scanline = (unsigned char *) STBTT_malloc(result->w, userdata);
   else
      scanline = scanline_data;

   y = off_y * vsubsample;
   e[n].y0 = (off_y + result->h) * (float) vsubsample + 1;

   while (j < result->h) {
      STBTT_memset(scanline, 0, result->w);
      for (s=0; s < vsubsample; ++s) {
         // find center of pixel for this scanline
         float scan_y = y + 0.5f;
         stbtt__active_edge **step = &active;

         // update all active edges;
         // remove all active edges that terminate before the center of this scanline
         while (*step) {
            stbtt__active_edge * z = *step;
            if (z->ey <= scan_y) {
               *step = z->next; // delete from list
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               STBTT_assert(z->direction);
               z->direction = 0;
               stbtt__hheap_free(&hh, z);
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            } else {
               z->x += z->dx; // advance to position for current scanline
               step = &((*step)->next); // advance through list
            }
         }

         // resort the list if needed
         for(;;) {
            int changed=0;
            step = &active;
            while (*step && (*step)->next) {
               if ((*step)->x > (*step)->next->x) {
                  stbtt__active_edge *t = *step;
                  stbtt__active_edge *q = t->next;

                  t->next = q->next;
                  q->next = t;
                  *step = q;
                  changed = 1;
               }
               step = &(*step)->next;
            }
            if (!changed) break;
         }

         // insert all edges that start before the center of this scanline -- omit ones that also end on this scanline
         while (e->y0 <= scan_y) {
            if (e->y1 > scan_y) {
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               stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y, userdata);
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               if (z != NULL) {
                  // find insertion point
                  if (active == NULL)
                     active = z;
                  else if (z->x < active->x) {
                     // insert at front
                     z->next = active;
                     active = z;
                  } else {
                     // find thing to insert AFTER
                     stbtt__active_edge *p = active;
                     while (p->next && p->next->x < z->x)
                        p = p->next;
                     // at this point, p->next->x is NOT < z->x
                     z->next = p->next;
                     p->next = z;
                  }
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               }
            }
            ++e;
         }

         // now process all active edges in XOR fashion
         if (active)
            stbtt__fill_active_edges(scanline, result->w, active, max_weight);

         ++y;
      }
      STBTT_memcpy(result->pixels + j * result->stride, scanline, result->w);
      ++j;
   }

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   stbtt__hheap_cleanup(&hh, userdata);

   if (scanline != scanline_data)
      STBTT_free(scanline, userdata);
}

#elif STBTT_RASTERIZER_VERSION == 2

// the edge passed in here does not cross the vertical line at x or the vertical line at x+1
// (i.e. it has already been clipped to those)
static void stbtt__handle_clipped_edge(float *scanline, int x, stbtt__active_edge *e, float x0, float y0, float x1, float y1)
{
   if (y0 == y1) return;
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   STBTT_assert(y0 < y1);
   STBTT_assert(e->sy <= e->ey);
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   if (y0 > e->ey) return;
   if (y1 < e->sy) return;
   if (y0 < e->sy) {
      x0 += (x1-x0) * (e->sy - y0) / (y1-y0);
      y0 = e->sy;
   }
   if (y1 > e->ey) {
      x1 += (x1-x0) * (e->ey - y1) / (y1-y0);
      y1 = e->ey;
   }

   if (x0 == x)
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      STBTT_assert(x1 <= x+1);
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   else if (x0 == x+1)
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      STBTT_assert(x1 >= x);
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   else if (x0 <= x)
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      STBTT_assert(x1 <= x);
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   else if (x0 >= x+1)
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      STBTT_assert(x1 >= x+1);
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   else
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      STBTT_assert(x1 >= x && x1 <= x+1);
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   if (x0 <= x && x1 <= x)
      scanline[x] += e->direction * (y1-y0);
   else if (x0 >= x+1 && x1 >= x+1)
      ;
   else {
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      STBTT_assert(x0 >= x && x0 <= x+1 && x1 >= x && x1 <= x+1);
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      scanline[x] += e->direction * (y1-y0) * (1-((x0-x)+(x1-x))/2); // coverage = 1 - average x position
   }
}

static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill, int len, stbtt__active_edge *e, float y_top)
{
   float y_bottom = y_top+1;

   while (e) {
      // brute force every pixel

      // compute intersection points with top & bottom
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      STBTT_assert(e->ey >= y_top);
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      if (e->fdx == 0) {
         float x0 = e->fx;
         if (x0 < len) {
            if (x0 >= 0) {
               stbtt__handle_clipped_edge(scanline,(int) x0,e, x0,y_top, x0,y_bottom);
               stbtt__handle_clipped_edge(scanline_fill-1,(int) x0+1,e, x0,y_top, x0,y_bottom);
            } else {
               stbtt__handle_clipped_edge(scanline_fill-1,0,e, x0,y_top, x0,y_bottom);
            }
         }
      } else {
         float x0 = e->fx;
         float dx = e->fdx;
         float xb = x0 + dx;
         float x_top, x_bottom;
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         float sy0,sy1;
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         float dy = e->fdy;
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         STBTT_assert(e->sy <= y_bottom && e->ey >= y_top);
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         // compute endpoints of line segment clipped to this scanline (if the
         // line segment starts on this scanline. x0 is the intersection of the
         // line with y_top, but that may be off the line segment.
         if (e->sy > y_top) {
            x_top = x0 + dx * (e->sy - y_top);
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            sy0 = e->sy;
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         } else {
            x_top = x0;
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            sy0 = y_top;
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         }
         if (e->ey < y_bottom) {
            x_bottom = x0 + dx * (e->ey - y_top);
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            sy1 = e->ey;
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         } else {
            x_bottom = xb;
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            sy1 = y_bottom;
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         }

         if (x_top >= 0 && x_bottom >= 0 && x_top < len && x_bottom < len) {
            // from here on, we don't have to range check x values

            if ((int) x_top == (int) x_bottom) {
               float height;
               // simple case, only spans one pixel
               int x = (int) x_top;
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               height = sy1 - sy0;
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               STBTT_assert(x >= 0 && x < len);
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               scanline[x] += e->direction * (1-((x_top - x) + (x_bottom-x))/2)  * height;
               scanline_fill[x] += e->direction * height; // everything right of this pixel is filled
            } else {
               int x,x1,x2;
               float y_crossing, step, sign, area;
               // covers 2+ pixels
               if (x_top > x_bottom) {
                  // flip scanline vertically; signed area is the same
                  float t;
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                  sy0 = y_bottom - (sy0 - y_top);
                  sy1 = y_bottom - (sy1 - y_top);
                  t = sy0, sy0 = sy1, sy1 = t;
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                  t = x_bottom, x_bottom = x_top, x_top = t;
                  dx = -dx;
                  dy = -dy;
                  t = x0, x0 = xb, xb = t;
               }

               x1 = (int) x_top;
               x2 = (int) x_bottom;
               // compute intersection with y axis at x1+1
               y_crossing = (x1+1 - x0) * dy + y_top;

               sign = e->direction;
               // area of the rectangle covered from y0..y_crossing
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               area = sign * (y_crossing-sy0);
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               // area of the triangle (x_top,y0), (x+1,y0), (x+1,y_crossing)
               scanline[x1] += area * (1-((x_top - x1)+(x1+1-x1))/2);

               step = sign * dy;
               for (x = x1+1; x < x2; ++x) {
                  scanline[x] += area + step/2;
                  area += step;
               }
               y_crossing += dy * (x2 - (x1+1));

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               STBTT_assert(STBTT_fabs(area) <= 1.01f);
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               scanline[x2] += area + sign * (1-((x2-x2)+(x_bottom-x2))/2) * (sy1-y_crossing);
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               scanline_fill[x2] += sign * (sy1-sy0);
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            }
         } else {
            // if edge goes outside of box we're drawing, we require
            // clipping logic. since this does not match the intended use
            // of this library, we use a different, very slow brute
            // force implementation
            int x;
            for (x=0; x < len; ++x) {
               // cases:
               //
               // there can be up to two intersections with the pixel. any intersection
               // with left or right edges can be handled by splitting into two (or three)
               // regions. intersections with top & bottom do not necessitate case-wise logic.
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               //
               // the old way of doing this found the intersections with the left & right edges,
               // then used some simple logic to produce up to three segments in sorted order
               // from top-to-bottom. however, this had a problem: if an x edge was epsilon
               // across the x border, then the corresponding y position might not be distinct
               // from the other y segment, and it might ignored as an empty segment. to avoid
               // that, we need to explicitly produce segments based on x positions.

               // rename variables to clear pairs
               float y0 = y_top;
               float x1 = (float) (x);
               float x2 = (float) (x+1);
               float x3 = xb;
               float y3 = y_bottom;
               float y1,y2;

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               // x = e->x + e->dx * (y-y_top)
               // (y-y_top) = (x - e->x) / e->dx
               // y = (x - e->x) / e->dx + y_top
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               y1 = (x - x0) / dx + y_top;
               y2 = (x+1 - x0) / dx + y_top;

               if (x0 < x1 && x3 > x2) {         // three segments descending down-right
                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x2,y2);
                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
               } else if (x3 < x1 && x0 > x2) {  // three segments descending down-left
                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x1,y1);
                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
               } else if (x0 < x1 && x3 > x1) {  // two segments across x, down-right
                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
               } else if (x3 < x1 && x0 > x1) {  // two segments across x, down-left
                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
               } else if (x0 < x2 && x3 > x2) {  // two segments across x+1, down-right
                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
               } else if (x3 < x2 && x0 > x2) {  // two segments across x+1, down-left
                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
               } else {  // one segment
                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x3,y3);
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               }
            }
         }
      }
      e = e->next;
   }
}

// directly AA rasterize edges w/o supersampling
static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
{
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   stbtt__active_edge *active = NULL;
   int y,j=0, i;
   float scanline_data[129], *scanline, *scanline2;

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   STBTT__NOTUSED(vsubsample);

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   if (result->w > 64)
      scanline = (float *) STBTT_malloc((result->w*2+1) * sizeof(float), userdata);
   else
      scanline = scanline_data;

   scanline2 = scanline + result->w;

   y = off_y;
   e[n].y0 = (float) (off_y + result->h) + 1;

   while (j < result->h) {
      // find center of pixel for this scanline
      float scan_y_top    = y + 0.0f;
      float scan_y_bottom = y + 1.0f;
      stbtt__active_edge **step = &active;

      STBTT_memset(scanline , 0, result->w*sizeof(scanline[0]));
      STBTT_memset(scanline2, 0, (result->w+1)*sizeof(scanline[0]));

      // update all active edges;
      // remove all active edges that terminate before the top of this scanline
      while (*step) {
         stbtt__active_edge * z = *step;
         if (z->ey <= scan_y_top) {
            *step = z->next; // delete from list
            STBTT_assert(z->direction);
            z->direction = 0;
            stbtt__hheap_free(&hh, z);
         } else {
            step = &((*step)->next); // advance through list
         }
      }

      // insert all edges that start before the bottom of this scanline
      while (e->y0 <= scan_y_bottom) {
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         if (e->y0 != e->y1) {
            stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y_top, userdata);
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            if (z != NULL) {
               STBTT_assert(z->ey >= scan_y_top);
               // insert at front
               z->next = active;
               active = z;
            }
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         }
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         ++e;
      }

      // now process all active edges
      if (active)
         stbtt__fill_active_edges_new(scanline, scanline2+1, result->w, active, scan_y_top);

      {
         float sum = 0;
         for (i=0; i < result->w; ++i) {
            float k;
            int m;
            sum += scanline2[i];
            k = scanline[i] + sum;
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            k = (float) STBTT_fabs(k)*255 + 0.5f;
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            m = (int) k;
            if (m > 255) m = 255;
            result->pixels[j*result->stride + i] = (unsigned char) m;
         }
      }
      // advance all the edges
      step = &active;
      while (*step) {
         stbtt__active_edge *z = *step;
         z->fx += z->fdx; // advance to position for current scanline
         step = &((*step)->next); // advance through list
      }

      ++y;
      ++j;
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   }

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   stbtt__hheap_cleanup(&hh, userdata);

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   if (scanline != scanline_data)
      STBTT_free(scanline, userdata);
}
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#else
#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
#endif

#define STBTT__COMPARE(a,b)  ((a)->y0 < (b)->y0)

static void stbtt__sort_edges_ins_sort(stbtt__edge *p, int n)
{
   int i,j;
   for (i=1; i < n; ++i) {
      stbtt__edge t = p[i], *a = &t;
      j = i;
      while (j > 0) {
         stbtt__edge *b = &p[j-1];
         int c = STBTT__COMPARE(a,b);
         if (!c) break;
         p[j] = p[j-1];
         --j;
      }
      if (i != j)
         p[j] = t;
   }
}
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static void stbtt__sort_edges_quicksort(stbtt__edge *p, int n)
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{
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   /* threshhold for transitioning to insertion sort */
   while (n > 12) {
      stbtt__edge t;
      int c01,c12,c,m,i,j;

      /* compute median of three */
      m = n >> 1;
      c01 = STBTT__COMPARE(&p[0],&p[m]);
      c12 = STBTT__COMPARE(&p[m],&p[n-1]);
      /* if 0 >= mid >= end, or 0 < mid < end, then use mid */
      if (c01 != c12) {
         /* otherwise, we'll need to swap something else to middle */
         int z;
         c = STBTT__COMPARE(&p[0],&p[n-1]);
         /* 0>mid && mid<n:  0>n => n; 0<n => 0 */
         /* 0<mid && mid>n:  0>n => 0; 0<n => n */
         z = (c == c12) ? 0 : n-1;
         t = p[z];
         p[z] = p[m];
         p[m] = t;
      }
      /* now p[m] is the median-of-three */
      /* swap it to the beginning so it won't move around */
      t = p[0];
      p[0] = p[m];
      p[m] = t;

      /* partition loop */
      i=1;
      j=n-1;
      for(;;) {
         /* handling of equality is crucial here */
         /* for sentinels & efficiency with duplicates */
         for (;;++i) {
            if (!STBTT__COMPARE(&p[i], &p[0])) break;
         }
         for (;;--j) {
            if (!STBTT__COMPARE(&p[0], &p[j])) break;
         }
         /* make sure we haven't crossed */
         if (i >= j) break;
         t = p[i];
         p[i] = p[j];
         p[j] = t;

         ++i;
         --j;
      }
      /* recurse on smaller side, iterate on larger */
      if (j < (n-i)) {
         stbtt__sort_edges_quicksort(p,j);
         p = p+i;
         n = n-i;
      } else {
         stbtt__sort_edges_quicksort(p+i, n-i);
         n = j;
      }
   }
}
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static void stbtt__sort_edges(stbtt__edge *p, int n)
{
   stbtt__sort_edges_quicksort(p, n);
   stbtt__sort_edges_ins_sort(p, n);
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}

typedef struct
{
   float x,y;
} stbtt__point;

static void stbtt__rasterize(stbtt__bitmap *result, stbtt__point *pts, int *wcount, int windings, float scale_x, float scale_y, float shift_x, float shift_y, int off_x, int off_y, int invert, void *userdata)
{
   float y_scale_inv = invert ? -scale_y : scale_y;
   stbtt__edge *e;
   int n,i,j,k,m;
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#if STBTT_RASTERIZER_VERSION == 1
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   int vsubsample = result->h < 8 ? 15 : 5;
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#elif STBTT_RASTERIZER_VERSION == 2
   int vsubsample = 1;
#else
   #error "Unrecognized value of STBTT_RASTERIZER_VERSION"
#endif
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   // vsubsample should divide 255 evenly; otherwise we won't reach full opacity

   // now we have to blow out the windings into explicit edge lists
   n = 0;
   for (i=0; i < windings; ++i)
      n += wcount[i];

   e = (stbtt__edge *) STBTT_malloc(sizeof(*e) * (n+1), userdata); // add an extra one as a sentinel
   if (e == 0) return;
   n = 0;

   m=0;
   for (i=0; i < windings; ++i) {
      stbtt__point *p = pts + m;
      m += wcount[i];
      j = wcount[i]-1;
      for (k=0; k < wcount[i]; j=k++) {
         int a=k,b=j;
         // skip the edge if horizontal
         if (p[j].y == p[k].y)
            continue;
         // add edge from j to k to the list
         e[n].invert = 0;
         if (invert ? p[j].y > p[k].y : p[j].y < p[k].y) {
            e[n].invert = 1;
            a=j,b=k;
         }
         e[n].x0 = p[a].x * scale_x + shift_x;
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         e[n].y0 = (p[a].y * y_scale_inv + shift_y) * vsubsample;
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         e[n].x1 = p[b].x * scale_x + shift_x;
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         e[n].y1 = (p[b].y * y_scale_inv + shift_y) * vsubsample;
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         ++n;
      }
   }

   // now sort the edges by their highest point (should snap to integer, and then by x)
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   //STBTT_sort(e, n, sizeof(e[0]), stbtt__edge_compare);
   stbtt__sort_edges(e, n);
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   // now, traverse the scanlines and find the intersections on each scanline, use xor winding rule
   stbtt__rasterize_sorted_edges(result, e, n, vsubsample, off_x, off_y, userdata);

   STBTT_free(e, userdata);
}

static void stbtt__add_point(stbtt__point *points, int n, float x, float y)
{
   if (!points) return; // during first pass, it's unallocated
   points[n].x = x;
   points[n].y = y;
}

// tesselate until threshhold p is happy... @TODO warped to compensate for non-linear stretching
static int stbtt__tesselate_curve(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float objspace_flatness_squared, int n)
{
   // midpoint
   float mx = (x0 + 2*x1 + x2)/4;
   float my = (y0 + 2*y1 + y2)/4;
   // versus directly drawn line
   float dx = (x0+x2)/2 - mx;
   float dy = (y0+y2)/2 - my;
   if (n > 16) // 65536 segments on one curve better be enough!
      return 1;
   if (dx*dx+dy*dy > objspace_flatness_squared) { // half-pixel error allowed... need to be smaller if AA
      stbtt__tesselate_curve(points, num_points, x0,y0, (x0+x1)/2.0f,(y0+y1)/2.0f, mx,my, objspace_flatness_squared,n+1);
      stbtt__tesselate_curve(points, num_points, mx,my, (x1+x2)/2.0f,(y1+y2)/2.0f, x2,y2, objspace_flatness_squared,n+1);
   } else {
      stbtt__add_point(points, *num_points,x2,y2);
      *num_points = *num_points+1;
   }
   return 1;
}

// returns number of contours
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static stbtt__point *stbtt_FlattenCurves(stbtt_vertex *vertices, int num_verts, float objspace_flatness, int **contour_lengths, int *num_contours, void *userdata)
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{
   stbtt__point *points=0;
   int num_points=0;

   float objspace_flatness_squared = objspace_flatness * objspace_flatness;
   int i,n=0,start=0, pass;

   // count how many "moves" there are to get the contour count
   for (i=0; i < num_verts; ++i)
      if (vertices[i].type == STBTT_vmove)
         ++n;

   *num_contours = n;
   if (n == 0) return 0;

   *contour_lengths = (int *) STBTT_malloc(sizeof(**contour_lengths) * n, userdata);

   if (*contour_lengths == 0) {
      *num_contours = 0;
      return 0;
   }

   // make two passes through the points so we don't need to realloc
   for (pass=0; pass < 2; ++pass) {
      float x=0,y=0;
      if (pass == 1) {
         points = (stbtt__point *) STBTT_malloc(num_points * sizeof(points[0]), userdata);
         if (points == NULL) goto error;
      }
      num_points = 0;
      n= -1;
      for (i=0; i < num_verts; ++i) {
         switch (vertices[i].type) {
            case STBTT_vmove:
               // start the next contour
               if (n >= 0)
                  (*contour_lengths)[n] = num_points - start;
               ++n;
               start = num_points;

               x = vertices[i].x, y = vertices[i].y;
               stbtt__add_point(points, num_points++, x,y);
               break;
            case STBTT_vline:
               x = vertices[i].x, y = vertices[i].y;
               stbtt__add_point(points, num_points++, x, y);
               break;
            case STBTT_vcurve:
               stbtt__tesselate_curve(points, &num_points, x,y,
                                        vertices[i].cx, vertices[i].cy,
                                        vertices[i].x,  vertices[i].y,
                                        objspace_flatness_squared, 0);
               x = vertices[i].x, y = vertices[i].y;
               break;
         }
      }
      (*contour_lengths)[n] = num_points - start;
   }

   return points;
error:
   STBTT_free(points, userdata);
   STBTT_free(*contour_lengths, userdata);
   *contour_lengths = 0;
   *num_contours = 0;
   return NULL;
}

2406
STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result, float flatness_in_pixels, stbtt_vertex *vertices, int num_verts, float scale_x, float scale_y, float shift_x, float shift_y, int x_off, int y_off, int invert, void *userdata)
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{
   float scale = scale_x > scale_y ? scale_y : scale_x;
   int winding_count, *winding_lengths;
   stbtt__point *windings = stbtt_FlattenCurves(vertices, num_verts, flatness_in_pixels / scale, &winding_lengths, &winding_count, userdata);
   if (windings) {
      stbtt__rasterize(result, windings, winding_lengths, winding_count, scale_x, scale_y, shift_x, shift_y, x_off, y_off, invert, userdata);
      STBTT_free(winding_lengths, userdata);
      STBTT_free(windings, userdata);
   }
}

2418
STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata)
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{
   STBTT_free(bitmap, userdata);
}

2423
STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff)
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{
   int ix0,iy0,ix1,iy1;
   stbtt__bitmap gbm;
   stbtt_vertex *vertices;   
   int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);

   if (scale_x == 0) scale_x = scale_y;
   if (scale_y == 0) {
2432 2433 2434 2435
      if (scale_x == 0) {
         STBTT_free(vertices, info->userdata);
         return NULL;
      }
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      scale_y = scale_x;
   }

   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,&ix1,&iy1);

   // now we get the size
   gbm.w = (ix1 - ix0);
   gbm.h = (iy1 - iy0);
   gbm.pixels = NULL; // in case we error

   if (width ) *width  = gbm.w;
   if (height) *height = gbm.h;
   if (xoff  ) *xoff   = ix0;
   if (yoff  ) *yoff   = iy0;
   
   if (gbm.w && gbm.h) {
      gbm.pixels = (unsigned char *) STBTT_malloc(gbm.w * gbm.h, info->userdata);
      if (gbm.pixels) {
         gbm.stride = gbm.w;

         stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata);
      }
   }
   STBTT_free(vertices, info->userdata);
   return gbm.pixels;
}   

2463
STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff)
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{
   return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y, 0.0f, 0.0f, glyph, width, height, xoff, yoff);
}

2468
STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph)
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{
   int ix0,iy0;
   stbtt_vertex *vertices;
   int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);
   stbtt__bitmap gbm;   

   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,0,0);
   gbm.pixels = output;
   gbm.w = out_w;
   gbm.h = out_h;
   gbm.stride = out_stride;

   if (gbm.w && gbm.h)
      stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0,iy0, 1, info->userdata);

   STBTT_free(vertices, info->userdata);
}

2487
STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph)
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{
   stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, glyph);
}

2492
STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
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{
   return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y,shift_x,shift_y, stbtt_FindGlyphIndex(info,codepoint), width,height,xoff,yoff);
}   

2497
STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint)
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{
   stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, stbtt_FindGlyphIndex(info,codepoint));
}

2502
STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
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{
   return stbtt_GetCodepointBitmapSubpixel(info, scale_x, scale_y, 0.0f,0.0f, codepoint, width,height,xoff,yoff);
}   

2507
STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint)
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{
   stbtt_MakeCodepointBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, codepoint);
}

//////////////////////////////////////////////////////////////////////////////
//
// bitmap baking
//
// This is SUPER-CRAPPY packing to keep source code small

2518
static int stbtt_BakeFontBitmap_internal(unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
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                                float pixel_height,                     // height of font in pixels
                                unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
                                int first_char, int num_chars,          // characters to bake
                                stbtt_bakedchar *chardata)
{
   float scale;
   int x,y,bottom_y, i;
   stbtt_fontinfo f;
2527
   f.userdata = NULL;
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   if (!stbtt_InitFont(&f, data, offset))
      return -1;
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   STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels
   x=y=1;
   bottom_y = 1;

   scale = stbtt_ScaleForPixelHeight(&f, pixel_height);

   for (i=0; i < num_chars; ++i) {
      int advance, lsb, x0,y0,x1,y1,gw,gh;
      int g = stbtt_FindGlyphIndex(&f, first_char + i);
      stbtt_GetGlyphHMetrics(&f, g, &advance, &lsb);
      stbtt_GetGlyphBitmapBox(&f, g, scale,scale, &x0,&y0,&x1,&y1);
      gw = x1-x0;
      gh = y1-y0;
      if (x + gw + 1 >= pw)
         y = bottom_y, x = 1; // advance to next row
      if (y + gh + 1 >= ph) // check if it fits vertically AFTER potentially moving to next row
         return -i;
      STBTT_assert(x+gw < pw);
      STBTT_assert(y+gh < ph);
      stbtt_MakeGlyphBitmap(&f, pixels+x+y*pw, gw,gh,pw, scale,scale, g);
      chardata[i].x0 = (stbtt_int16) x;
      chardata[i].y0 = (stbtt_int16) y;
      chardata[i].x1 = (stbtt_int16) (x + gw);
      chardata[i].y1 = (stbtt_int16) (y + gh);
      chardata[i].xadvance = scale * advance;
      chardata[i].xoff     = (float) x0;
      chardata[i].yoff     = (float) y0;
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      x = x + gw + 1;
      if (y+gh+1 > bottom_y)
         bottom_y = y+gh+1;
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   }
   return bottom_y;
}

2564
STBTT_DEF void stbtt_GetBakedQuad(stbtt_bakedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int opengl_fillrule)
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{
   float d3d_bias = opengl_fillrule ? 0 : -0.5f;
   float ipw = 1.0f / pw, iph = 1.0f / ph;
   stbtt_bakedchar *b = chardata + char_index;
2569 2570
   int round_x = STBTT_ifloor((*xpos + b->xoff) + 0.5f);
   int round_y = STBTT_ifloor((*ypos + b->yoff) + 0.5f);
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   q->x0 = round_x + d3d_bias;
   q->y0 = round_y + d3d_bias;
   q->x1 = round_x + b->x1 - b->x0 + d3d_bias;
   q->y1 = round_y + b->y1 - b->y0 + d3d_bias;

   q->s0 = b->x0 * ipw;
   q->t0 = b->y0 * iph;
   q->s1 = b->x1 * ipw;
   q->t1 = b->y1 * iph;

   *xpos += b->xadvance;
}

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//////////////////////////////////////////////////////////////////////////////
//
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// rectangle packing replacement routines if you don't have stb_rect_pack.h
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//

#ifndef STB_RECT_PACK_VERSION

2592 2593
typedef int stbrp_coord;

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////////////////////////////////////////////////////////////////////////////////////
//                                                                                //
//                                                                                //
// COMPILER WARNING ?!?!?                                                         //
//                                                                                //
//                                                                                //
// if you get a compile warning due to these symbols being defined more than      //
// once, move #include "stb_rect_pack.h" before #include "stb_truetype.h"         //
//                                                                                //
////////////////////////////////////////////////////////////////////////////////////

typedef struct
{
   int width,height;
   int x,y,bottom_y;
} stbrp_context;

typedef struct
{
   unsigned char x;
} stbrp_node;

2616
struct stbrp_rect
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{
2618 2619
   stbrp_coord x,y;
   int id,w,h,was_packed;
2620
};
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static void stbrp_init_target(stbrp_context *con, int pw, int ph, stbrp_node *nodes, int num_nodes)
{
   con->width  = pw;
   con->height = ph;
   con->x = 0;
   con->y = 0;
   con->bottom_y = 0;
   STBTT__NOTUSED(nodes);
   STBTT__NOTUSED(num_nodes);   
}

static void stbrp_pack_rects(stbrp_context *con, stbrp_rect *rects, int num_rects)
{
   int i;
   for (i=0; i < num_rects; ++i) {
      if (con->x + rects[i].w > con->width) {
         con->x = 0;
         con->y = con->bottom_y;
      }
      if (con->y + rects[i].h > con->height)
         break;
      rects[i].x = con->x;
      rects[i].y = con->y;
      rects[i].was_packed = 1;
      con->x += rects[i].w;
      if (con->y + rects[i].h > con->bottom_y)
         con->bottom_y = con->y + rects[i].h;
   }
   for (   ; i < num_rects; ++i)
      rects[i].was_packed = 0;
}
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#endif

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//////////////////////////////////////////////////////////////////////////////
//
// bitmap baking
//
// This is SUPER-AWESOME (tm Ryan Gordon) packing using stb_rect_pack.h. If
// stb_rect_pack.h isn't available, it uses the BakeFontBitmap strategy.

2662
STBTT_DEF int stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int pw, int ph, int stride_in_bytes, int padding, void *alloc_context)
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{
   stbrp_context *context = (stbrp_context *) STBTT_malloc(sizeof(*context)            ,alloc_context);
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   int            num_nodes = pw - padding;
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   stbrp_node    *nodes   = (stbrp_node    *) STBTT_malloc(sizeof(*nodes  ) * num_nodes,alloc_context);

   if (context == NULL || nodes == NULL) {
      if (context != NULL) STBTT_free(context, alloc_context);
      if (nodes   != NULL) STBTT_free(nodes  , alloc_context);
      return 0;
   }

   spc->user_allocator_context = alloc_context;
   spc->width = pw;
   spc->height = ph;
   spc->pixels = pixels;
   spc->pack_info = context;
   spc->nodes = nodes;
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   spc->padding = padding;
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   spc->stride_in_bytes = stride_in_bytes != 0 ? stride_in_bytes : pw;
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   spc->h_oversample = 1;
   spc->v_oversample = 1;
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   stbrp_init_target(context, pw-padding, ph-padding, nodes, num_nodes);
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2687 2688
   if (pixels)
      STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels
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   return 1;
}

2693
STBTT_DEF void stbtt_PackEnd  (stbtt_pack_context *spc)
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{
   STBTT_free(spc->nodes    , spc->user_allocator_context);
   STBTT_free(spc->pack_info, spc->user_allocator_context);
}

2699
STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample)
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{
2701 2702
   STBTT_assert(h_oversample <= STBTT_MAX_OVERSAMPLE);
   STBTT_assert(v_oversample <= STBTT_MAX_OVERSAMPLE);
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   if (h_oversample <= STBTT_MAX_OVERSAMPLE)
      spc->h_oversample = h_oversample;
   if (v_oversample <= STBTT_MAX_OVERSAMPLE)
      spc->v_oversample = v_oversample;
}

#define STBTT__OVER_MASK  (STBTT_MAX_OVERSAMPLE-1)

static void stbtt__h_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
{
   unsigned char buffer[STBTT_MAX_OVERSAMPLE];
   int safe_w = w - kernel_width;
   int j;
2716
   STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
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   for (j=0; j < h; ++j) {
      int i;
      unsigned int total;
2720
      STBTT_memset(buffer, 0, kernel_width);
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      total = 0;

      // make kernel_width a constant in common cases so compiler can optimize out the divide
      switch (kernel_width) {
         case 2:
            for (i=0; i <= safe_w; ++i) {
               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
2730
               pixels[i] = (unsigned char) (total / 2);
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            }
            break;
         case 3:
            for (i=0; i <= safe_w; ++i) {
               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
2737
               pixels[i] = (unsigned char) (total / 3);
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            }
            break;
         case 4:
            for (i=0; i <= safe_w; ++i) {
               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
2744
               pixels[i] = (unsigned char) (total / 4);
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            }
            break;
2747 2748 2749 2750 2751 2752 2753
         case 5:
            for (i=0; i <= safe_w; ++i) {
               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
               pixels[i] = (unsigned char) (total / 5);
            }
            break;
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         default:
            for (i=0; i <= safe_w; ++i) {
               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
2758
               pixels[i] = (unsigned char) (total / kernel_width);
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            }
            break;
      }

      for (; i < w; ++i) {
2764
         STBTT_assert(pixels[i] == 0);
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         total -= buffer[i & STBTT__OVER_MASK];
2766
         pixels[i] = (unsigned char) (total / kernel_width);
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      }

      pixels += stride_in_bytes;
   }
}

static void stbtt__v_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
{
   unsigned char buffer[STBTT_MAX_OVERSAMPLE];
   int safe_h = h - kernel_width;
   int j;
2778
   STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
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   for (j=0; j < w; ++j) {
      int i;
      unsigned int total;
2782
      STBTT_memset(buffer, 0, kernel_width);
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      total = 0;

      // make kernel_width a constant in common cases so compiler can optimize out the divide
      switch (kernel_width) {
         case 2:
            for (i=0; i <= safe_h; ++i) {
               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
2792
               pixels[i*stride_in_bytes] = (unsigned char) (total / 2);
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            }
            break;
         case 3:
            for (i=0; i <= safe_h; ++i) {
               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
2799
               pixels[i*stride_in_bytes] = (unsigned char) (total / 3);
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            }
            break;
         case 4:
            for (i=0; i <= safe_h; ++i) {
               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
2806
               pixels[i*stride_in_bytes] = (unsigned char) (total / 4);
S
Sean Barrett 已提交
2807 2808
            }
            break;
2809 2810 2811 2812 2813 2814 2815
         case 5:
            for (i=0; i <= safe_h; ++i) {
               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
               pixels[i*stride_in_bytes] = (unsigned char) (total / 5);
            }
            break;
S
Sean Barrett 已提交
2816 2817 2818 2819
         default:
            for (i=0; i <= safe_h; ++i) {
               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
2820
               pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width);
S
Sean Barrett 已提交
2821 2822 2823 2824 2825
            }
            break;
      }

      for (; i < h; ++i) {
2826
         STBTT_assert(pixels[i*stride_in_bytes] == 0);
S
Sean Barrett 已提交
2827
         total -= buffer[i & STBTT__OVER_MASK];
2828
         pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width);
S
Sean Barrett 已提交
2829 2830 2831 2832 2833 2834
      }

      pixels += 1;
   }
}

2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846
static float stbtt__oversample_shift(int oversample)
{
   if (!oversample)
      return 0.0f;

   // The prefilter is a box filter of width "oversample",
   // which shifts phase by (oversample - 1)/2 pixels in
   // oversampled space. We want to shift in the opposite
   // direction to counter this.
   return (float)-(oversample - 1) / (2.0f * (float)oversample);
}

2847
// rects array must be big enough to accommodate all characters in the given ranges
2848
STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
S
Sean Barrett 已提交
2849
{
2850
   int i,j,k;
S
Sean Barrett 已提交
2851 2852 2853 2854

   k=0;
   for (i=0; i < num_ranges; ++i) {
      float fh = ranges[i].font_size;
2855
      float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
2856 2857 2858
      ranges[i].h_oversample = (unsigned char) spc->h_oversample;
      ranges[i].v_oversample = (unsigned char) spc->v_oversample;
      for (j=0; j < ranges[i].num_chars; ++j) {
S
Sean Barrett 已提交
2859
         int x0,y0,x1,y1;
2860
         int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
2861
         int glyph = stbtt_FindGlyphIndex(info, codepoint);
2862 2863 2864 2865 2866
         stbtt_GetGlyphBitmapBoxSubpixel(info,glyph,
                                         scale * spc->h_oversample,
                                         scale * spc->v_oversample,
                                         0,0,
                                         &x0,&y0,&x1,&y1);
2867 2868
         rects[k].w = (stbrp_coord) (x1-x0 + spc->padding + spc->h_oversample-1);
         rects[k].h = (stbrp_coord) (y1-y0 + spc->padding + spc->v_oversample-1);
S
Sean Barrett 已提交
2869 2870 2871 2872
         ++k;
      }
   }

2873 2874 2875 2876
   return k;
}

// rects array must be big enough to accommodate all characters in the given ranges
2877
STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
2878 2879
{
   int i,j,k, return_value = 1;
S
Sean Barrett 已提交
2880

2881 2882 2883 2884
   // save current values
   int old_h_over = spc->h_oversample;
   int old_v_over = spc->v_oversample;

S
Sean Barrett 已提交
2885 2886 2887
   k = 0;
   for (i=0; i < num_ranges; ++i) {
      float fh = ranges[i].font_size;
2888
      float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
2889 2890 2891 2892 2893 2894 2895 2896
      float recip_h,recip_v,sub_x,sub_y;
      spc->h_oversample = ranges[i].h_oversample;
      spc->v_oversample = ranges[i].v_oversample;
      recip_h = 1.0f / spc->h_oversample;
      recip_v = 1.0f / spc->v_oversample;
      sub_x = stbtt__oversample_shift(spc->h_oversample);
      sub_y = stbtt__oversample_shift(spc->v_oversample);
      for (j=0; j < ranges[i].num_chars; ++j) {
S
Sean Barrett 已提交
2897 2898
         stbrp_rect *r = &rects[k];
         if (r->was_packed) {
S
Sean Barrett 已提交
2899
            stbtt_packedchar *bc = &ranges[i].chardata_for_range[j];
S
Sean Barrett 已提交
2900
            int advance, lsb, x0,y0,x1,y1;
2901
            int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
2902
            int glyph = stbtt_FindGlyphIndex(info, codepoint);
2903
            stbrp_coord pad = (stbrp_coord) spc->padding;
S
Sean Barrett 已提交
2904

S
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2905
            // pad on left and top
2906 2907 2908 2909
            r->x += pad;
            r->y += pad;
            r->w -= pad;
            r->h -= pad;
2910 2911
            stbtt_GetGlyphHMetrics(info, glyph, &advance, &lsb);
            stbtt_GetGlyphBitmapBox(info, glyph,
S
Sean Barrett 已提交
2912 2913 2914
                                    scale * spc->h_oversample,
                                    scale * spc->v_oversample,
                                    &x0,&y0,&x1,&y1);
2915
            stbtt_MakeGlyphBitmapSubpixel(info,
S
Sean Barrett 已提交
2916
                                          spc->pixels + r->x + r->y*spc->stride_in_bytes,
S
Sean Barrett 已提交
2917 2918
                                          r->w - spc->h_oversample+1,
                                          r->h - spc->v_oversample+1,
S
Sean Barrett 已提交
2919
                                          spc->stride_in_bytes,
S
Sean Barrett 已提交
2920 2921 2922
                                          scale * spc->h_oversample,
                                          scale * spc->v_oversample,
                                          0,0,
S
Sean Barrett 已提交
2923
                                          glyph);
S
Sean Barrett 已提交
2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934

            if (spc->h_oversample > 1)
               stbtt__h_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
                                  r->w, r->h, spc->stride_in_bytes,
                                  spc->h_oversample);

            if (spc->v_oversample > 1)
               stbtt__v_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
                                  r->w, r->h, spc->stride_in_bytes,
                                  spc->v_oversample);

S
Sean Barrett 已提交
2935 2936
            bc->x0       = (stbtt_int16)  r->x;
            bc->y0       = (stbtt_int16)  r->y;
S
Sean Barrett 已提交
2937 2938
            bc->x1       = (stbtt_int16) (r->x + r->w);
            bc->y1       = (stbtt_int16) (r->y + r->h);
S
Sean Barrett 已提交
2939
            bc->xadvance =                scale * advance;
S
Sean Barrett 已提交
2940 2941 2942 2943
            bc->xoff     =       (float)  x0 * recip_h + sub_x;
            bc->yoff     =       (float)  y0 * recip_v + sub_y;
            bc->xoff2    =                (x0 + r->w) * recip_h + sub_x;
            bc->yoff2    =                (y0 + r->h) * recip_v + sub_y;
S
Sean Barrett 已提交
2944 2945 2946 2947 2948 2949 2950 2951
         } else {
            return_value = 0; // if any fail, report failure
         }

         ++k;
      }
   }

2952 2953 2954 2955
   // restore original values
   spc->h_oversample = old_h_over;
   spc->v_oversample = old_v_over;

S
Sean Barrett 已提交
2956 2957 2958
   return return_value;
}

2959 2960
STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects)
{
S
Sean Barrett 已提交
2961
   stbrp_pack_rects((stbrp_context *) spc->pack_info, rects, num_rects);
2962 2963
}

2964
STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges)
2965 2966 2967
{
   stbtt_fontinfo info;
   int i,j,n, return_value = 1;
2968
   //stbrp_context *context = (stbrp_context *) spc->pack_info;
2969 2970 2971 2972
   stbrp_rect    *rects;

   // flag all characters as NOT packed
   for (i=0; i < num_ranges; ++i)
2973
      for (j=0; j < ranges[i].num_chars; ++j)
2974 2975 2976 2977 2978 2979 2980
         ranges[i].chardata_for_range[j].x0 =
         ranges[i].chardata_for_range[j].y0 =
         ranges[i].chardata_for_range[j].x1 =
         ranges[i].chardata_for_range[j].y1 = 0;

   n = 0;
   for (i=0; i < num_ranges; ++i)
2981
      n += ranges[i].num_chars;
2982 2983 2984 2985 2986
         
   rects = (stbrp_rect *) STBTT_malloc(sizeof(*rects) * n, spc->user_allocator_context);
   if (rects == NULL)
      return 0;

2987
   info.userdata = spc->user_allocator_context;
2988 2989 2990 2991
   stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata,font_index));

   n = stbtt_PackFontRangesGatherRects(spc, &info, ranges, num_ranges, rects);

2992
   stbtt_PackFontRangesPackRects(spc, rects, n);
2993 2994 2995
  
   return_value = stbtt_PackFontRangesRenderIntoRects(spc, &info, ranges, num_ranges, rects);

2996
   STBTT_free(rects, spc->user_allocator_context);
2997 2998 2999
   return return_value;
}

3000
STBTT_DEF int stbtt_PackFontRange(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, float font_size,
3001
            int first_unicode_codepoint_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range)
S
Sean Barrett 已提交
3002 3003
{
   stbtt_pack_range range;
3004 3005 3006
   range.first_unicode_codepoint_in_range = first_unicode_codepoint_in_range;
   range.array_of_unicode_codepoints = NULL;
   range.num_chars                   = num_chars_in_range;
S
Sean Barrett 已提交
3007 3008 3009 3010 3011
   range.chardata_for_range          = chardata_for_range;
   range.font_size                   = font_size;
   return stbtt_PackFontRanges(spc, fontdata, font_index, &range, 1);
}

3012
STBTT_DEF void stbtt_GetPackedQuad(stbtt_packedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int align_to_integer)
S
Sean Barrett 已提交
3013 3014 3015 3016 3017
{
   float ipw = 1.0f / pw, iph = 1.0f / ph;
   stbtt_packedchar *b = chardata + char_index;

   if (align_to_integer) {
3018 3019
      float x = (float) STBTT_ifloor((*xpos + b->xoff) + 0.5f);
      float y = (float) STBTT_ifloor((*ypos + b->yoff) + 0.5f);
S
Sean Barrett 已提交
3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039
      q->x0 = x;
      q->y0 = y;
      q->x1 = x + b->xoff2 - b->xoff;
      q->y1 = y + b->yoff2 - b->yoff;
   } else {
      q->x0 = *xpos + b->xoff;
      q->y0 = *ypos + b->yoff;
      q->x1 = *xpos + b->xoff2;
      q->y1 = *ypos + b->yoff2;
   }

   q->s0 = b->x0 * ipw;
   q->t0 = b->y0 * iph;
   q->s1 = b->x1 * ipw;
   q->t1 = b->y1 * iph;

   *xpos += b->xadvance;
}


S
Sean Barrett 已提交
3040 3041 3042 3043 3044 3045
//////////////////////////////////////////////////////////////////////////////
//
// font name matching -- recommended not to use this
//

// check if a utf8 string contains a prefix which is the utf16 string; if so return length of matching utf8 string
3046
static stbtt_int32 stbtt__CompareUTF8toUTF16_bigendian_prefix(stbtt_uint8 *s1, stbtt_int32 len1, stbtt_uint8 *s2, stbtt_int32 len2) 
S
Sean Barrett 已提交
3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084
{
   stbtt_int32 i=0;

   // convert utf16 to utf8 and compare the results while converting
   while (len2) {
      stbtt_uint16 ch = s2[0]*256 + s2[1];
      if (ch < 0x80) {
         if (i >= len1) return -1;
         if (s1[i++] != ch) return -1;
      } else if (ch < 0x800) {
         if (i+1 >= len1) return -1;
         if (s1[i++] != 0xc0 + (ch >> 6)) return -1;
         if (s1[i++] != 0x80 + (ch & 0x3f)) return -1;
      } else if (ch >= 0xd800 && ch < 0xdc00) {
         stbtt_uint32 c;
         stbtt_uint16 ch2 = s2[2]*256 + s2[3];
         if (i+3 >= len1) return -1;
         c = ((ch - 0xd800) << 10) + (ch2 - 0xdc00) + 0x10000;
         if (s1[i++] != 0xf0 + (c >> 18)) return -1;
         if (s1[i++] != 0x80 + ((c >> 12) & 0x3f)) return -1;
         if (s1[i++] != 0x80 + ((c >>  6) & 0x3f)) return -1;
         if (s1[i++] != 0x80 + ((c      ) & 0x3f)) return -1;
         s2 += 2; // plus another 2 below
         len2 -= 2;
      } else if (ch >= 0xdc00 && ch < 0xe000) {
         return -1;
      } else {
         if (i+2 >= len1) return -1;
         if (s1[i++] != 0xe0 + (ch >> 12)) return -1;
         if (s1[i++] != 0x80 + ((ch >> 6) & 0x3f)) return -1;
         if (s1[i++] != 0x80 + ((ch     ) & 0x3f)) return -1;
      }
      s2 += 2;
      len2 -= 2;
   }
   return i;
}

3085
static int stbtt_CompareUTF8toUTF16_bigendian_internal(char *s1, int len1, char *s2, int len2) 
S
Sean Barrett 已提交
3086
{
3087
   return len1 == stbtt__CompareUTF8toUTF16_bigendian_prefix((stbtt_uint8*) s1, len1, (stbtt_uint8*) s2, len2);
S
Sean Barrett 已提交
3088 3089 3090 3091
}

// returns results in whatever encoding you request... but note that 2-byte encodings
// will be BIG-ENDIAN... use stbtt_CompareUTF8toUTF16_bigendian() to compare
3092
STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID)
S
Sean Barrett 已提交
3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127
{
   stbtt_int32 i,count,stringOffset;
   stbtt_uint8 *fc = font->data;
   stbtt_uint32 offset = font->fontstart;
   stbtt_uint32 nm = stbtt__find_table(fc, offset, "name");
   if (!nm) return NULL;

   count = ttUSHORT(fc+nm+2);
   stringOffset = nm + ttUSHORT(fc+nm+4);
   for (i=0; i < count; ++i) {
      stbtt_uint32 loc = nm + 6 + 12 * i;
      if (platformID == ttUSHORT(fc+loc+0) && encodingID == ttUSHORT(fc+loc+2)
          && languageID == ttUSHORT(fc+loc+4) && nameID == ttUSHORT(fc+loc+6)) {
         *length = ttUSHORT(fc+loc+8);
         return (const char *) (fc+stringOffset+ttUSHORT(fc+loc+10));
      }
   }
   return NULL;
}

static int stbtt__matchpair(stbtt_uint8 *fc, stbtt_uint32 nm, stbtt_uint8 *name, stbtt_int32 nlen, stbtt_int32 target_id, stbtt_int32 next_id)
{
   stbtt_int32 i;
   stbtt_int32 count = ttUSHORT(fc+nm+2);
   stbtt_int32 stringOffset = nm + ttUSHORT(fc+nm+4);

   for (i=0; i < count; ++i) {
      stbtt_uint32 loc = nm + 6 + 12 * i;
      stbtt_int32 id = ttUSHORT(fc+loc+6);
      if (id == target_id) {
         // find the encoding
         stbtt_int32 platform = ttUSHORT(fc+loc+0), encoding = ttUSHORT(fc+loc+2), language = ttUSHORT(fc+loc+4);

         // is this a Unicode encoding?
         if (platform == 0 || (platform == 3 && encoding == 1) || (platform == 3 && encoding == 10)) {
3128 3129
            stbtt_int32 slen = ttUSHORT(fc+loc+8);
            stbtt_int32 off = ttUSHORT(fc+loc+10);
S
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3130 3131 3132 3133 3134 3135

            // check if there's a prefix match
            stbtt_int32 matchlen = stbtt__CompareUTF8toUTF16_bigendian_prefix(name, nlen, fc+stringOffset+off,slen);
            if (matchlen >= 0) {
               // check for target_id+1 immediately following, with same encoding & language
               if (i+1 < count && ttUSHORT(fc+loc+12+6) == next_id && ttUSHORT(fc+loc+12) == platform && ttUSHORT(fc+loc+12+2) == encoding && ttUSHORT(fc+loc+12+4) == language) {
3136 3137
                  slen = ttUSHORT(fc+loc+12+8);
                  off = ttUSHORT(fc+loc+12+10);
S
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3138 3139 3140 3141 3142
                  if (slen == 0) {
                     if (matchlen == nlen)
                        return 1;
                  } else if (matchlen < nlen && name[matchlen] == ' ') {
                     ++matchlen;
3143
                     if (stbtt_CompareUTF8toUTF16_bigendian_internal((char*) (name+matchlen), nlen-matchlen, (char*)(fc+stringOffset+off),slen))
S
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3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188
                        return 1;
                  }
               } else {
                  // if nothing immediately following
                  if (matchlen == nlen)
                     return 1;
               }
            }
         }

         // @TODO handle other encodings
      }
   }
   return 0;
}

static int stbtt__matches(stbtt_uint8 *fc, stbtt_uint32 offset, stbtt_uint8 *name, stbtt_int32 flags)
{
   stbtt_int32 nlen = (stbtt_int32) STBTT_strlen((char *) name);
   stbtt_uint32 nm,hd;
   if (!stbtt__isfont(fc+offset)) return 0;

   // check italics/bold/underline flags in macStyle...
   if (flags) {
      hd = stbtt__find_table(fc, offset, "head");
      if ((ttUSHORT(fc+hd+44) & 7) != (flags & 7)) return 0;
   }

   nm = stbtt__find_table(fc, offset, "name");
   if (!nm) return 0;

   if (flags) {
      // if we checked the macStyle flags, then just check the family and ignore the subfamily
      if (stbtt__matchpair(fc, nm, name, nlen, 16, -1))  return 1;
      if (stbtt__matchpair(fc, nm, name, nlen,  1, -1))  return 1;
      if (stbtt__matchpair(fc, nm, name, nlen,  3, -1))  return 1;
   } else {
      if (stbtt__matchpair(fc, nm, name, nlen, 16, 17))  return 1;
      if (stbtt__matchpair(fc, nm, name, nlen,  1,  2))  return 1;
      if (stbtt__matchpair(fc, nm, name, nlen,  3, -1))  return 1;
   }

   return 0;
}

3189
static int stbtt_FindMatchingFont_internal(unsigned char *font_collection, char *name_utf8, stbtt_int32 flags)
S
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3190 3191 3192 3193 3194 3195 3196 3197 3198 3199
{
   stbtt_int32 i;
   for (i=0;;++i) {
      stbtt_int32 off = stbtt_GetFontOffsetForIndex(font_collection, i);
      if (off < 0) return off;
      if (stbtt__matches((stbtt_uint8 *) font_collection, off, (stbtt_uint8*) name_utf8, flags))
         return off;
   }
}

3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235
#if defined(__GNUC__) || defined(__clang__)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wcast-qual"
#endif

STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,
                                float pixel_height, unsigned char *pixels, int pw, int ph,
                                int first_char, int num_chars, stbtt_bakedchar *chardata)
{
   return stbtt_BakeFontBitmap_internal((unsigned char *) data, offset, pixel_height, pixels, pw, ph, first_char, num_chars, chardata);
}

STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index)
{
   return stbtt_GetFontOffsetForIndex_internal((unsigned char *) data, index);   
}

STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset)
{
   return stbtt_InitFont_internal(info, (unsigned char *) data, offset);
}

STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags)
{
   return stbtt_FindMatchingFont_internal((unsigned char *) fontdata, (char *) name, flags);
}

STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2)
{
   return stbtt_CompareUTF8toUTF16_bigendian_internal((char *) s1, len1, (char *) s2, len2);
}

#if defined(__GNUC__) || defined(__clang__)
#pragma GCC diagnostic pop
#endif

S
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#endif // STB_TRUETYPE_IMPLEMENTATION
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// FULL VERSION HISTORY
//
S
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//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
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//   1.11 (2016-04-02) fix unused-variable warning
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//   1.10 (2016-04-02) allow user-defined fabs() replacement
//                     fix memory leak if fontsize=0.0
//                     fix warning from duplicate typedef
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//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use alloc userdata for PackFontRanges
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//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
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//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
//                     allow PackFontRanges to pack and render in separate phases;
//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
//                     fixed an assert() bug in the new rasterizer
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//                     replace assert() with STBTT_assert() in new rasterizer
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//   1.06 (2015-07-14) performance improvements (~35% faster on x86 and x64 on test machine)
//                     also more precise AA rasterizer, except if shapes overlap
//                     remove need for STBTT_sort
//   1.05 (2015-04-15) fix misplaced definitions for STBTT_STATIC
//   1.04 (2015-04-15) typo in example
//   1.03 (2015-04-12) STBTT_STATIC, fix memory leak in new packing, various fixes
//   1.02 (2014-12-10) fix various warnings & compile issues w/ stb_rect_pack, C++
//   1.01 (2014-12-08) fix subpixel position when oversampling to exactly match
//                        non-oversampled; STBTT_POINT_SIZE for packed case only
//   1.00 (2014-12-06) add new PackBegin etc. API, w/ support for oversampling
//   0.99 (2014-09-18) fix multiple bugs with subpixel rendering (ryg)
//   0.9  (2014-08-07) support certain mac/iOS fonts without an MS platformID
//   0.8b (2014-07-07) fix a warning
//   0.8  (2014-05-25) fix a few more warnings
//   0.7  (2013-09-25) bugfix: subpixel glyph bug fixed in 0.5 had come back
//   0.6c (2012-07-24) improve documentation
//   0.6b (2012-07-20) fix a few more warnings
//   0.6  (2012-07-17) fix warnings; added stbtt_ScaleForMappingEmToPixels,
//                        stbtt_GetFontBoundingBox, stbtt_IsGlyphEmpty
//   0.5  (2011-12-09) bugfixes:
//                        subpixel glyph renderer computed wrong bounding box
//                        first vertex of shape can be off-curve (FreeSans)
//   0.4b (2011-12-03) fixed an error in the font baking example
//   0.4  (2011-12-01) kerning, subpixel rendering (tor)
//                    bugfixes for:
//                        codepoint-to-glyph conversion using table fmt=12
//                        codepoint-to-glyph conversion using table fmt=4
//                        stbtt_GetBakedQuad with non-square texture (Zer)
//                    updated Hello World! sample to use kerning and subpixel
//                    fixed some warnings
//   0.3  (2009-06-24) cmap fmt=12, compound shapes (MM)
//                    userdata, malloc-from-userdata, non-zero fill (stb)
//   0.2  (2009-03-11) Fix unsigned/signed char warnings
//   0.1  (2009-03-09) First public release
//