gpu: Defer reads from default framebuffer when needed.

gpu/command_buffer/build_gles2_cmd_buffer.py

 #!/usr/bin/env python
 # 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.
 
 """code generator for GLES2 command buffers."""
 
 import itertools
 import os
 import os.path
@@ skipping 1162 matching lines @@
     'gen_func': 'GenRenderbuffersEXT',
   },
   'BindTexture': {
     'type': 'Bind',
     'decoder_func': 'DoBindTexture',
     'gen_func': 'GenTextures',
     # TODO(gman): remove this once client side caching works.
     'client_test': False,
   },
   'BlitFramebufferEXT': {
-    'decoder_func': 'DoBlitFramebufferEXT',
+    'type': 'ManualService',
     'unit_test': False,
     'extension': True,
     'pepper_interface': 'FramebufferBlit',

[greggman, 2012/11/30 02:49:01]

Would be better to add add a couple of flags here?

'defer_draw': True,
'defer_read': True,

And adjust the generation code?

[piman, 2012/11/30 04:52:34]

Done.

   },
   'BufferData': {
     'type': 'Manual',
     'immediate': True,
     'client_test': False,
   },
   'BufferSubData': {
     'type': 'Data',
     'client_test': False,
     'decoder_func': 'DoBufferSubData',
   },
   'CheckFramebufferStatus': {
     'type': 'Is',
     'decoder_func': 'DoCheckFramebufferStatus',
     'gl_test_func': 'glCheckFramebufferStatusEXT',
     'error_value': 'GL_FRAMEBUFFER_UNSUPPORTED',
     'result': ['GLenum'],
   },
   'Clear': {
-    'type': 'Manual',
-    'cmd_args': 'GLbitfield mask'
+    'type': 'ManualService',
   },
   'ClearColor': {
     'type': 'StateSet',
     'state': 'ClearColor',
   },
   'ClearDepthf': {
     'type': 'StateSet',
     'state': 'ClearDepthf',
     'decoder_func': 'glClearDepth',
     'gl_test_func': 'glClearDepth',
@@ skipping 36 matching lines @@
     'type': 'Manual',
     'immediate': True,
     'bucket': True,
   },
   'CompressedTexSubImage2D': {
     'type': 'Data',
     'bucket': True,
     'decoder_func': 'DoCompressedTexSubImage2D',
   },
   'CopyTexImage2D': {
-    'decoder_func': 'DoCopyTexImage2D',
+    'type': 'ManualService',
     'unit_test': False,
   },
   'CopyTexSubImage2D': {
-    'decoder_func': 'DoCopyTexSubImage2D',
+    'type': 'ManualService',
   },
   'CreateProgram': {
     'type': 'Create',
     'client_test': False,
   },
   'CreateShader': {
     'type': 'Create',
     'client_test': False,
   },
   'BlendColor': {
@@ skipping 1960 matching lines @@
 
   def WriteImmediateCmdGetTotalSize(self, func, file):
     """Overrriden from TypeHandler."""
     # TODO(gman): Move this data to _FUNCTION_INFO?
     if func.name == 'ShaderSourceImmediate':
       file.Write("    uint32 total_size = ComputeSize(_data_size);\n")
     else:
       CustomHandler.WriteImmediateCmdGetTotalSize(self, func, file)
 
 
+class ManualServiceHandler(TypeHandler):
+  """Handler for commands that are auto-generated but for the service side."""
+
+  def __init__(self):
+    TypeHandler.__init__(self)
+
+  def WriteServiceImplementation(self, func, file):
+    """Overrriden from TypeHandler."""
+    pass
+
+  def WriteImmediateServiceImplementation(self, func, file):
+    """Overrriden from TypeHandler."""
+    pass
+
+  def WriteBucketServiceImplementation(self, func, file):
+    """Overrriden from TypeHandler."""
+    pass
+
+
 class DataHandler(TypeHandler):
   """Handler for glBufferData, glBufferSubData, glTexImage2D, glTexSubImage2D,
      glCompressedTexImage2D, glCompressedTexImageSub2D."""
   def __init__(self):
     TypeHandler.__init__(self)
 
   def InitFunction(self, func):
     """Overrriden from TypeHandler."""
     if func.name == 'CompressedTexSubImage2DBucket':
       func.cmd_args = func.cmd_args[:-1]
@@ skipping 3148 matching lines @@
       'Data': DataHandler(),
       'Delete': DeleteHandler(),
       'DELn': DELnHandler(),
       'GENn': GENnHandler(),
       'GETn': GETnHandler(),
       'GLchar': GLcharHandler(),
       'GLcharN': GLcharNHandler(),
       'HandWritten': HandWrittenHandler(),
       'Is': IsHandler(),
       'Manual': ManualHandler(),
+      'ManualService': ManualServiceHandler(),
       'PUT': PUTHandler(),
       'PUTn': PUTnHandler(),
       'PUTXn': PUTXnHandler(),
       'StateSet': StateSetHandler(),
       'StateSetRGBAlpha': StateSetRGBAlphaHandler(),
       'StateSetFrontBack': StateSetFrontBackHandler(),
       'StateSetFrontBackSeparate': StateSetFrontBackSeparateHandler(),
       'STRn': STRnHandler(),
       'Todo': TodoHandler(),
     }
@@ skipping 998 matching lines @@
     gen.WriteGLES2Header("../../third_party/khronos/GLES2/gl2chromium.h")
 
   if gen.errors > 0:
     print "%d errors" % gen.errors
     return 1
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))