Add EXT_color_buffer_half_float extension support in GPU commandbuffer service.

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <stdio.h>
 
 #include <algorithm>
 #include <list>
@@ skipping 6790 matching lines @@
         }
         break;
       }
       default:
         break;
     }
   }
 }
 
 
+static inline GLenum GetTexType(GLenum type) {
+  if (gfx::GetGLImplementation() != gfx::kGLImplementationEGLGLES2) {
+    if (type == GL_HALF_FLOAT_OES)
+      return GL_HALF_FLOAT_ARB;
+  }
+  return type;
+}
+
 error::Error GLES2DecoderImpl::HandleReadPixels(
     uint32 immediate_data_size, const cmds::ReadPixels& c) {
   if (ShouldDeferReads())
     return error::kDeferCommandUntilLater;
   GLint x = c.x;
   GLint y = c.y;
   GLsizei width = c.width;
   GLsizei height = c.height;
   GLenum format = c.format;
   GLenum type = c.type;
@@ skipping 85 matching lines @@
     GLint read_width = read_end_x - read_x;
     for (GLint yy = 0; yy < height; ++yy) {
       GLint ry = y + yy;
 
       // Clear the row.
       memset(dst, 0, unpadded_row_size);
 
       // If the row is in range, copy it.
       if (ry >= 0 && ry < max_size.height() && read_width > 0) {
         glReadPixels(
-            read_x, ry, read_width, 1, format, type, dst + dest_row_offset);
+            read_x, ry, read_width, 1, format, GetTexType(type),
+            dst + dest_row_offset);
       }
       dst += padded_row_size;
     }
   } else {
     if (async && features().use_async_readpixels) {
       GLuint buffer;
       glGenBuffersARB(1, &buffer);
       glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, buffer);
       glBufferData(GL_PIXEL_PACK_BUFFER_ARB, pixels_size, NULL, GL_STREAM_READ);
       GLenum error = glGetError();
       if (error == GL_NO_ERROR) {
-        glReadPixels(x, y, width, height, format, type, 0);
+        glReadPixels(x, y, width, height, format, GetTexType(type), 0);
         pending_readpixel_fences_.push(linked_ptr<FenceCallback>(
             new FenceCallback()));
         WaitForReadPixels(base::Bind(
             &GLES2DecoderImpl::FinishReadPixels,
             base::internal::SupportsWeakPtrBase::StaticAsWeakPtr
             <GLES2DecoderImpl>(this),
             c, buffer));
         glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, 0);
         return error::kNoError;
       }
     }
-    glReadPixels(x, y, width, height, format, type, pixels);
+    glReadPixels(x, y, width, height, format, GetTexType(type), pixels);
   }
   GLenum error = LOCAL_PEEK_GL_ERROR("glReadPixels");
   if (error == GL_NO_ERROR) {
     if (result != NULL) {
       *result = true;
     }
     FinishReadPixels(c, 0);
   }
 
   return error::kNoError;
@@ skipping 3498 matching lines @@
   return error::kNoError;
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu