gpu: fix CopyTextureCHROMIUM for immutable texture.

gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.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_copy_texture_chromium.h"
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "gpu/command_buffer/service/gl_utils.h"
@@ skipping 200 matching lines @@
   }
 #endif
   return true;
 }
 
 void DoCopyTexImage2D(const gpu::gles2::GLES2Decoder* decoder,
                       GLenum source_target,
                       GLuint source_id,
                       GLuint dest_id,
                       GLint dest_level,
-                      GLenum dest_internal_format,
                       GLsizei width,
                       GLsizei height,
                       GLuint framebuffer) {
   DCHECK(source_target == GL_TEXTURE_2D ||
          source_target == GL_TEXTURE_RECTANGLE_ARB);
   if (BindFramebufferTexture2D(
           source_target, source_id, 0 /* level */, framebuffer)) {
     glBindTexture(GL_TEXTURE_2D, dest_id);
     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-    glCopyTexImage2D(GL_TEXTURE_2D,
-                     dest_level,
-                     dest_internal_format,
-                     0 /* x */,
-                     0 /* y */,
-                     width,
-                     height,
-                     0 /* border */);
+    glCopyTexSubImage2D(GL_TEXTURE_2D, dest_level, 0 /* xoffset */,
+                        0 /* yoffset */, 0 /* x */, 0 /* y */, width, height);
   }
 
   decoder->RestoreTextureState(source_id);
   decoder->RestoreTextureState(dest_id);
   decoder->RestoreTextureUnitBindings(0);
   decoder->RestoreActiveTexture();
   decoder->RestoreFramebufferBindings();
 }
 
 }  // namespace
@@ skipping 73 matching lines @@
     bool premultiply_alpha,
     bool unpremultiply_alpha) {
   bool premultiply_alpha_change = premultiply_alpha ^ unpremultiply_alpha;
   // GL_INVALID_OPERATION is generated if the currently bound framebuffer's
   // format does not contain a superset of the components required by the base
   // format of internalformat.
   // https://www.khronos.org/opengles/sdk/docs/man/xhtml/glCopyTexImage2D.xml
   bool source_format_contain_superset_of_dest_format =
       source_internal_format == dest_internal_format ||
       (source_internal_format == GL_RGBA && dest_internal_format == GL_RGB);
-  // GL_TEXTURE_RECTANGLE_ARB on FBO is supported by OpenGL, not GLES2,
-  // so restrict this to GL_TEXTURE_2D.

[dshwang, 2014/11/20 15:23:07]

ARB_texture_rectangle spec[1] don't mention about FBO.
I tests it using mesa egl driver, and work well on GLES3.

[1] https://www.opengl.org/registry/specs/ARB/texture_rectangle.txt

-  if (source_target == GL_TEXTURE_2D && !flip_y && !premultiply_alpha_change &&
+  bool source_target_allowed = source_target == GL_TEXTURE_2D ||
+                               source_target == GL_TEXTURE_RECTANGLE_ARB;
+  if (source_target_allowed && !flip_y && !premultiply_alpha_change &&
       source_format_contain_superset_of_dest_format) {
     DoCopyTexImage2D(decoder,
                      source_target,
                      source_id,
                      dest_id,
                      dest_level,
-                     dest_internal_format,
                      width,
                      height,
                      framebuffer_);
     return;
   }
 
   // Use default transform matrix if no transform passed in.
   const static GLfloat default_matrix[16] = {1.0f, 0.0f, 0.0f, 0.0f,
                                              0.0f, 1.0f, 0.0f, 0.0f,
                                              0.0f, 0.0f, 1.0f, 0.0f,
@@ skipping 118 matching lines @@
   decoder->RestoreTextureState(dest_id);
   decoder->RestoreTextureUnitBindings(0);
   decoder->RestoreActiveTexture();
   decoder->RestoreProgramBindings();
   decoder->RestoreBufferBindings();
   decoder->RestoreFramebufferBindings();
   decoder->RestoreGlobalState();
 }
 
 }  // namespace gpu