console: add qemu_pixelformat_from_pixman

Function to convert pixman format codes to qemu PixelFormat.

[ Benjamin Herrenschmidt: fix BGRA+RGBA shifts ]
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

include/ui/qemu-pixman.h

@@ -33,6 +33,7 @@
 
 /* -------------------------------------------------------------------- */
 
+PixelFormat qemu_pixelformat_from_pixman(pixman_format_code_t format);
 int qemu_pixman_get_type(int rshift, int gshift, int bshift);
 pixman_format_code_t qemu_pixman_get_format(PixelFormat *pf);
 

ui/qemu-pixman.c

@@ -6,6 +6,62 @@
 #include "qemu-common.h"
 #include "ui/console.h"
 
+PixelFormat qemu_pixelformat_from_pixman(pixman_format_code_t format)
+{
+    PixelFormat pf;
+    uint8_t bpp;
+
+    bpp = pf.bits_per_pixel = PIXMAN_FORMAT_BPP(format);
+    pf.bytes_per_pixel = PIXMAN_FORMAT_BPP(format) / 8;
+    pf.depth = PIXMAN_FORMAT_DEPTH(format);
+
+    pf.abits = PIXMAN_FORMAT_A(format);
+    pf.rbits = PIXMAN_FORMAT_R(format);
+    pf.gbits = PIXMAN_FORMAT_G(format);
+    pf.bbits = PIXMAN_FORMAT_B(format);
+
+    switch (PIXMAN_FORMAT_TYPE(format)) {
+    case PIXMAN_TYPE_ARGB:
+        pf.ashift = pf.bbits + pf.gbits + pf.rbits;
+        pf.rshift = pf.bbits + pf.gbits;
+        pf.gshift = pf.bbits;
+        pf.bshift = 0;
+        break;
+    case PIXMAN_TYPE_ABGR:
+        pf.ashift = pf.rbits + pf.gbits + pf.bbits;
+        pf.bshift = pf.rbits + pf.gbits;
+        pf.gshift = pf.rbits;
+        pf.rshift = 0;
+        break;
+    case PIXMAN_TYPE_BGRA:
+	pf.bshift = bpp - pf.bbits;
+        pf.gshift = bpp - (pf.bbits + pf.gbits);
+        pf.rshift = bpp - (pf.bbits + pf.gbits + pf.rbits);
+        pf.ashift = 0;
+        break;
+    case PIXMAN_TYPE_RGBA:
+        pf.rshift = bpp - pf.rbits;
+        pf.gshift = bpp - (pf.rbits + pf.gbits);
+        pf.bshift = bpp - (pf.rbits + pf.gbits + pf.bbits);
+        pf.ashift = 0;
+        break;
+    default:
+        g_assert_not_reached();
+        break;
+    }
+
+    pf.amax = (1 << pf.abits) - 1;
+    pf.rmax = (1 << pf.rbits) - 1;
+    pf.gmax = (1 << pf.gbits) - 1;
+    pf.bmax = (1 << pf.bbits) - 1;
+    pf.amask = pf.amax << pf.ashift;
+    pf.rmask = pf.rmax << pf.rshift;
+    pf.gmask = pf.gmax << pf.gshift;
+    pf.bmask = pf.bmax << pf.bshift;
+
+    return pf;
+}
+
 int qemu_pixman_get_type(int rshift, int gshift, int bshift)
 {
     int type = PIXMAN_TYPE_OTHER;