freetype: add script to create more hinting tests.

R=bsiegert, r
CC=golang-dev
https://codereview.appspot.com/14414044

cmd/print-glyph-points/main.c

 /*
-gcc main.c -I/usr/include/freetype2 -lfreetype && ./a.out
+gcc main.c -I/usr/include/freetype2 -lfreetype && ./a.out 12 ../../testdata/luxisr.ttf with_hinting
 */
 
 #include <stdio.h>
 #include <ft2build.h>
 #include FT_FREETYPE_H
 
-static int font_size = 12;
-static int no_hinting = 0;
+void usage(char** argv) {
+	printf("usage: %s font_size font_file [with_hinting|sans_hinting]\n", argv[0]);
+}
 
 int main(int argc, char** argv) {
 	FT_Error error;
 	FT_Library library;
 	FT_Face face;
 	FT_Outline* o;
-	int i, j;
+	int i, j, font_size, no_hinting;
 
+	if (argc != 4) {
+		usage(argv);
+		return 1;
+	}
+	font_size = atoi(argv[1]);
+	if (font_size <= 0) {
+		printf("invalid font_size\n");
+		usage(argv);
+		return 1;
+	}
+	if (!strcmp(argv[3], "with_hinting")) {
+		no_hinting = 0;
+	} else if (!strcmp(argv[3], "sans_hinting")) {
+		no_hinting = 1;
+	} else {
+		printf("neither \"with_hinting\" nor \"sans_hinting\"\n");
+		usage(argv);
+		return 1;
+	};
 	error = FT_Init_FreeType(&library);
 	if (error) {
 		printf("FT_Init_FreeType: error #%d\n", error);
 		return 1;
 	}
-	error = FT_New_Face(library, "../../testdata/luxisr.ttf", 0, &face);
+	error = FT_New_Face(library, argv[2], 0, &face);
 	if (error) {
 		printf("FT_New_Face: error #%d\n", error);
 		return 1;
@@ -50,4 +70,5 @@ int main(int argc, char** argv) {
 		}
 		printf("\n");
 	}
+	return 0;
 }

freetype/truetype/truetype_test.go

@@ -74,63 +74,106 @@ func TestParse(t *testing.T) {
 	}
 }
 
-func testScaling(t *testing.T, filename string, hinter *Hinter) {
-	b, err := ioutil.ReadFile("../../testdata/luxisr.ttf")
-	if err != nil {
-		t.Fatalf("ReadFile: %v", err)
-	}
-	font, err := Parse(b)
-	if err != nil {
-		t.Fatalf("Parse: %v", err)
-	}
-	f, err := os.Open("../../testdata/" + filename)
-	if err != nil {
-		t.Fatalf("Open: %v", err)
-	}
-	defer f.Close()
+var scalingTestCases = []struct {
+	name string
+	size int32
+	// hintingBrokenAt, if non-negative, is the glyph index n for which
+	// only the first n glyphs are known to be correctly hinted.
+	// TODO: remove this field, when hinting is completely implemented.
+	hintingBrokenAt int
+}{
+	{"luxisr", 12, -1},
+	// TODO: uncomment the fonts below, once they get past Parse and
+	// GlyphBuf.Load, and the unhinted values match C Freetype.
+	//{"x-arial-bold", 11, 0},
+	//{"x-deja-vu-sans-oblique", 17, 0},
+	//{"x-droid-sans-japanese", 9, 0},
+	//{"x-inconsolata", 10, 0},
+	//{"x-times-new-roman", 13, 0},
+}
 
-	wants := [][]Point{}
-	scanner := bufio.NewScanner(f)
-	for scanner.Scan() {
-		text := scanner.Text()
-		if text == "" {
-			wants = append(wants, []Point{})
-			continue
-		}
-		ss := strings.Split(text, ",")
-		points := make([]Point, len(ss))
-		for i, s := range ss {
-			p := &points[i]
-			if _, err := fmt.Sscanf(s, "%d %d %d", &p.X, &p.Y, &p.Flags); err != nil {
-				t.Fatalf("Sscanf: %v", err)
+func testScaling(t *testing.T, hinter *Hinter) {
+loop:
+	for _, tc := range scalingTestCases {
+		b, err := ioutil.ReadFile(fmt.Sprintf("../../testdata/%s.ttf", tc.name))
+		if err != nil {
+			// The "x-foo" fonts are optional tests, as they are not checked
+			// in for copyright or file size reasons.
+			if strings.HasPrefix(tc.name, "x-") {
+				t.Logf("%s: ReadFile: %v", tc.name, err)
+			} else {
+				t.Errorf("%s: ReadFile: %v", tc.name, err)
 			}
+			continue loop
 		}
-		wants = append(wants, points)
-	}
-	if err := scanner.Err(); err != nil && err != io.EOF {
-		t.Fatalf("Scanner: %v", err)
-	}
+		font, err := Parse(b)
+		if err != nil {
+			t.Errorf("%s: Parse: %v", tc.name, err)
+			continue loop
+		}
+		hinting := "sans"
+		if hinter != nil {
+			hinting = "with"
+		}
+		f, err := os.Open(fmt.Sprintf(
+			"../../testdata/%s-%dpt-%s-hinting.txt", tc.name, tc.size, hinting))
+		if err != nil {
+			t.Errorf("%s: Open: %v", tc.name, err)
+			continue loop
+		}
+		defer f.Close()
 
-	const fontSize = 12
-	glyphBuf := NewGlyphBuf()
-	for i, want := range wants {
-		if err = glyphBuf.Load(font, fontSize*64, Index(i), hinter); err != nil {
-			t.Fatalf("Load: %v", err)
+		wants := [][]Point{}
+		scanner := bufio.NewScanner(f)
+		for scanner.Scan() {
+			text := scanner.Text()
+			if text == "" {
+				wants = append(wants, []Point{})
+				continue
+			}
+			ss := strings.Split(text, ",")
+			points := make([]Point, len(ss))
+			for i, s := range ss {
+				p := &points[i]
+				if _, err := fmt.Sscanf(s, "%d %d %d", &p.X, &p.Y, &p.Flags); err != nil {
+					t.Errorf("%s: Sscanf: %v", tc.name, err)
+					continue loop
+				}
+			}
+			wants = append(wants, points)
 		}
-		got := glyphBuf.Point
-		for i := range got {
-			got[i].Flags &= 0x01
+		if err := scanner.Err(); err != nil && err != io.EOF {
+			t.Errorf("%s: Scanner: %v", tc.name, err)
+			continue loop
 		}
-		if !reflect.DeepEqual(got, want) {
-			t.Errorf("glyph #%d:\ngot  %v\nwant %v\n", i, got, want)
+
+		glyphBuf := NewGlyphBuf()
+		for i, want := range wants {
+			// TODO: completely implement hinting. For now, only the first
+			// tc.hintingBrokenAt glyphs of the test case's font are correctly hinted.
+			if hinter != nil && i == tc.hintingBrokenAt {
+				break
+			}
+
+			if err = glyphBuf.Load(font, tc.size*64, Index(i), hinter); err != nil {
+				t.Errorf("%s: glyph #%d: Load: %v", tc.name, i, err)
+				continue loop
+			}
+			got := glyphBuf.Point
+			for i := range got {
+				got[i].Flags &= 0x01
+			}
+			if !reflect.DeepEqual(got, want) {
+				t.Errorf("%s: glyph #%d:\ngot  %v\nwant %v\n", tc.name, i, got, want)
+			}
 		}
 	}
 }
 
 func TestScalingSansHinting(t *testing.T) {
-	testScaling(t, "luxisr-12pt-sans-hinting.txt", nil)
+	testScaling(t, nil)
 }
 
 func TestScalingWithHinting(t *testing.T) {
-	testScaling(t, "luxisr-12pt-with-hinting.txt", &Hinter{})
+	testScaling(t, &Hinter{})
 }

testdata/README

-The *.ttf and COPYING files in this directory were copied from the X.org
+The luxi*.ttf and COPYING files in this directory were copied from the X.org
 project, specifically
 http://xorg.freedesktop.org/releases/individual/font/font-bh-ttf-1.0.0.tar.bz2
 
-There are three fonts: sans (s), serif (r) and monospaced (m). For example,
+There are three Luxi fonts: sans (s), serif (r) and monospaced (m). For example,
 luxisr.ttf is Luxi Sans. The 'r' here means regular, as opposed to bold.
 
 The *.ttx files in this directory were generated from the *.ttf files

testdata/make-other-hinting-txts.sh

+#!/usr/bin/env bash
+#
+# This script creates the optional x-*-hinting.txt files from fonts that are
+# not checked in for copyright or file size reasons.
+#
+# Run it from this directory (testdata).
+#
+# It has only been tested on an Ubuntu 12.04 system.
+
+set -e
+
+: ${FONTDIR:=/usr/share/fonts/truetype}
+
+ln -sf $FONTDIR/droid/DroidSansJapanese.ttf       x-droid-sans-japanese.ttf
+ln -sf $FONTDIR/msttcorefonts/Arial_Bold.ttf      x-arial-bold.ttf 
+ln -sf $FONTDIR/msttcorefonts/Times_New_Roman.ttf x-times-new-roman.ttf
+ln -sf $FONTDIR/ttf-dejavu/DejaVuSans-Oblique.ttf x-deja-vu-sans-oblique.ttf
+
+${CC:=gcc} ../cmd/print-glyph-points/main.c $(pkg-config --cflags --libs freetype2) -o print-glyph-points
+
+./print-glyph-points  9 x-droid-sans-japanese.ttf sans_hinting  > x-droid-sans-japanese-9pt-sans-hinting.txt
+./print-glyph-points  9 x-droid-sans-japanese.ttf with_hinting  > x-droid-sans-japanese-9pt-with-hinting.txt
+./print-glyph-points 11 x-arial-bold.ttf sans_hinting           > x-arial-bold-11pt-sans-hinting.txt
+./print-glyph-points 11 x-arial-bold.ttf with_hinting           > x-arial-bold-11pt-with-hinting.txt
+./print-glyph-points 13 x-times-new-roman.ttf sans_hinting      > x-times-new-roman-13pt-sans-hinting.txt
+./print-glyph-points 13 x-times-new-roman.ttf with_hinting      > x-times-new-roman-13pt-with-hinting.txt
+./print-glyph-points 17 x-deja-vu-sans-oblique.ttf sans_hinting > x-deja-vu-sans-oblique-17pt-sans-hinting.txt
+./print-glyph-points 17 x-deja-vu-sans-oblique.ttf with_hinting > x-deja-vu-sans-oblique-17pt-with-hinting.txt
+
+rm print-glyph-points