Adding support for PVRTC, ATC, and ETC1 textures to the command buffer

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 3553a7addd858e7cb242b33d42bf54ab83c16e32..fd925b1eda8842890a3da1cd3bda38604504d2a2 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -7920,15 +7920,17 @@ const int kS3TCBlockWidth = 4;
 const int kS3TCBlockHeight = 4;
 const int kS3TCDXT1BlockSize = 8;
 const int kS3TCDXT3AndDXT5BlockSize = 16;
-const int kETC1BlockWidth = 4;
-const int kETC1BlockHeight = 4;
-const int kETC1BlockSize = 8;
 
 bool IsValidDXTSize(GLint level, GLsizei size) {
   return (size == 1) ||
          (size == 2) || !(size % kS3TCBlockWidth);
 }
 
+bool IsValidPVRTCSize(GLint level, GLsizei size) {
+  // Ensure that the size is a power of two
+  return (size & (size - 1)) == 0;
+}
+
 }  // anonymous namespace.
 
 bool GLES2DecoderImpl::ValidateCompressedTexFuncData(
@@ -7937,8 +7939,10 @@ bool GLES2DecoderImpl::ValidateCompressedTexFuncData(
   unsigned int bytes_required = 0;
 
   switch (format) {
+    case GL_ATC_RGB_AMD:
     case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
-    case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT: {
+    case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
+    case GL_ETC1_RGB8_OES: {
         int num_blocks_across =
             (width + kS3TCBlockWidth - 1) / kS3TCBlockWidth;
         int num_blocks_down =
@@ -7947,6 +7951,8 @@ bool GLES2DecoderImpl::ValidateCompressedTexFuncData(
         bytes_required = num_blocks * kS3TCDXT1BlockSize;
         break;
       }
+    case GL_ATC_RGBA_EXPLICIT_ALPHA_AMD:
+    case GL_ATC_RGBA_INTERPOLATED_ALPHA_AMD:
     case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
     case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT: {
         int num_blocks_across =
@@ -7957,13 +7963,14 @@ bool GLES2DecoderImpl::ValidateCompressedTexFuncData(
         bytes_required = num_blocks * kS3TCDXT3AndDXT5BlockSize;
         break;
       }
-    case GL_ETC1_RGB8_OES: {
-        int num_blocks_across =
-            (width + kETC1BlockWidth - 1) / kETC1BlockWidth;
-        int num_blocks_down =
-            (height + kETC1BlockHeight - 1) / kETC1BlockHeight;
-        int num_blocks = num_blocks_across * num_blocks_down;
-        bytes_required = num_blocks * kETC1BlockSize;
+    case GL_COMPRESSED_RGB_PVRTC_4BPPV1_IMG:
+    case GL_COMPRESSED_RGBA_PVRTC_4BPPV1_IMG: {
+        bytes_required = (std::max(width, 8) * std::max(height, 8) * 4 + 7)/8;
+        break;
+      }
+    case GL_COMPRESSED_RGB_PVRTC_2BPPV1_IMG:
+    case GL_COMPRESSED_RGBA_PVRTC_2BPPV1_IMG: {
+        bytes_required = (std::max(width, 16) * std::max(height, 8) * 2 + 7)/8;
         break;
       }
     default:
@@ -7996,7 +8003,10 @@ bool GLES2DecoderImpl::ValidateCompressedTexDimensions(
       }
       return true;
     }
-    case GL_ETC1_RGB8_OES:
+    case GL_ATC_RGB_AMD:
+    case GL_ATC_RGBA_EXPLICIT_ALPHA_AMD:
+    case GL_ATC_RGBA_INTERPOLATED_ALPHA_AMD:
+    case GL_ETC1_RGB8_OES: {
       if (width <= 0 || height <= 0) {
         LOCAL_SET_GL_ERROR(
             GL_INVALID_OPERATION, function_name,
@@ -8004,6 +8014,20 @@ bool GLES2DecoderImpl::ValidateCompressedTexDimensions(
         return false;
       }
       return true;
+    }
+    case GL_COMPRESSED_RGB_PVRTC_4BPPV1_IMG:
+    case GL_COMPRESSED_RGB_PVRTC_2BPPV1_IMG:
+    case GL_COMPRESSED_RGBA_PVRTC_4BPPV1_IMG:
+    case GL_COMPRESSED_RGBA_PVRTC_2BPPV1_IMG: {
+      if (!IsValidPVRTCSize(level, width) ||
+          !IsValidPVRTCSize(level, height)) {
+        LOCAL_SET_GL_ERROR(
+            GL_INVALID_OPERATION, function_name,
+            "width or height invalid for level");
+        return false;
+      }
+      return true;
+    }
     default:
       return false;
   }
@@ -8045,12 +8069,43 @@ bool GLES2DecoderImpl::ValidateCompressedTexSubDimensions(
       return ValidateCompressedTexDimensions(
           function_name, level, width, height, format);
     }
+    case GL_ATC_RGB_AMD:
+    case GL_ATC_RGBA_EXPLICIT_ALPHA_AMD:
+    case GL_ATC_RGBA_INTERPOLATED_ALPHA_AMD: {
+      LOCAL_SET_GL_ERROR(
+          GL_INVALID_OPERATION, function_name,
+          "not supported for ATC textures");
+      return false;
+    }
     case GL_ETC1_RGB8_OES: {
       LOCAL_SET_GL_ERROR(
           GL_INVALID_OPERATION, function_name,
           "not supported for ECT1_RGB8_OES textures");
       return false;
     }
+    case GL_COMPRESSED_RGB_PVRTC_4BPPV1_IMG:
+    case GL_COMPRESSED_RGB_PVRTC_2BPPV1_IMG:
+    case GL_COMPRESSED_RGBA_PVRTC_4BPPV1_IMG:
+    case GL_COMPRESSED_RGBA_PVRTC_2BPPV1_IMG: {
+      if ((xoffset != 0) || (yoffset != 0)) {
+        LOCAL_SET_GL_ERROR(
+            GL_INVALID_OPERATION, function_name,
+            "xoffset and yoffset must be zero");
+        return false;
+      }
+      GLsizei tex_width = 0;
+      GLsizei tex_height = 0;
+      if (!texture->GetLevelSize(target, level, &tex_width, &tex_height) ||
+          width != tex_width ||
+          height != tex_height) {
+        LOCAL_SET_GL_ERROR(
+            GL_INVALID_OPERATION, function_name,
+            "dimensions must match existing texture level dimensions");
+        return false;
+      }
+      return ValidateCompressedTexDimensions(
+          function_name, level, width, height, format);
+    }
     default:
       return false;
   }