cc: Adding ETC1 support to UIResourceBitmap and ResourceProvider

cc/resources/resource_provider.h

Index: cc/resources/resource_provider.h
diff --git a/cc/resources/resource_provider.h b/cc/resources/resource_provider.h
index df178194d943f080060e5b1f3e4f7a6e2e17d451..59bab813c709cf4e08f4ce8dc83acb5bedada91e 100644
--- a/cc/resources/resource_provider.h
+++ b/cc/resources/resource_provider.h
@@ -491,6 +491,7 @@ class CC_EXPORT ResourceProvider {
 inline unsigned BytesPerPixel(ResourceFormat format) {

[aelias_OOO_until_Jul13, 2013/10/18 01:59:24]

Please rename this method to BitsPerPixel and multiply everything by 8.  ETC1
would be 4.

[powei, 2013/10/23 05:36:15]

Done.

   DCHECK_LE(format, RESOURCE_FORMAT_MAX);
   static const unsigned format_bytes_per_pixel[RESOURCE_FORMAT_MAX + 1] = {
+    0,  // ETC1
     4,  // RGBA_8888
     2,  // RGBA_4444
     4,  // BGRA_8888
@@ -503,6 +504,7 @@ inline unsigned BytesPerPixel(ResourceFormat format) {
 inline GLenum GLDataType(ResourceFormat format) {
   DCHECK_LE(format, RESOURCE_FORMAT_MAX);
   static const unsigned format_gl_data_type[RESOURCE_FORMAT_MAX + 1] = {
+    GL_UNSIGNED_BYTE,           // ETC1
     GL_UNSIGNED_BYTE,           // RGBA_8888
     GL_UNSIGNED_SHORT_4_4_4_4,  // RGBA_4444
     GL_UNSIGNED_BYTE,           // BGRA_8888
@@ -515,11 +517,12 @@ inline GLenum GLDataType(ResourceFormat format) {
 inline GLenum GLDataFormat(ResourceFormat format) {
   DCHECK_LE(format, RESOURCE_FORMAT_MAX);
   static const unsigned format_gl_data_format[RESOURCE_FORMAT_MAX + 1] = {
-    GL_RGBA,       // RGBA_8888
-    GL_RGBA,       // RGBA_4444
-    GL_BGRA_EXT,   // BGRA_8888
-    GL_LUMINANCE,  // LUMINANCE_8
-    GL_RGB         // RGB_565
+    GL_ETC1_RGB8_OES,  // ETC1

[kaanb, 2013/10/18 16:54:49]

Is this a GL data format or a GL internal format? 

[powei, 2013/10/23 05:36:15]

If I'm reading the spec correctly.  We're suppose to use GL_ETC1_RGB8_OES for
the internal format in glCompressedTexImage2D and for the data format in
glCompressedTexSubImage2D

http://www.khronos.org/registry/gles/extensions/OES/OES_compressed_ETC1_RGB8_...

http://www.khronos.org/opengles/sdk/1.1/docs/man/glCompressedTexSubImage2D.xml

+    GL_RGBA,           // RGBA_8888
+    GL_RGBA,           // RGBA_4444
+    GL_BGRA_EXT,       // BGRA_8888
+    GL_LUMINANCE,      // LUMINANCE_8
+    GL_RGB             // RGB_565
   };
   return format_gl_data_format[format];
 }