Added booleans that indicate which GL extensions are available.

ui/gfx/gl/generate_bindings.py

 #!/usr/bin/python
 #
 # Copyright (c) 2011 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 GL/GLES extension wrangler."""
 
 import os
 import collections
@@ skipping 458 matching lines @@
   [GL_FUNCTIONS, 'gl', ['../../../third_party/mesa/MesaLib/include/GL/glext.h',
     '../../../gpu/GLES2/gl2ext.h']],
   [OSMESA_FUNCTIONS, 'osmesa', []],
   [EGL_FUNCTIONS, 'egl', ['../../../gpu/EGL/eglext.h']],
   [WGL_FUNCTIONS, 'wgl', [
     '../../../third_party/mesa/MesaLib/include/GL/wglext.h']],
   [GLX_FUNCTIONS, 'glx', [
     '../../../third_party/mesa/MesaLib/include/GL/glxext.h']],
 ]
 
-def GenerateHeader(file, functions, set_name):
+def GenerateHeader(file, functions, set_name, used_extension_functions):
   """Generates gl_binding_autogen_x.h"""
 
   # Write file header.
   file.write('// Copyright (c) 2011 The Chromium Authors. All rights reserved.\n')
   file.write('// Use of this source code is governed by a BSD-style license that can be\n')
   file.write('// found in the LICENSE file.\n')
   file.write('\n')
   file.write('// This file is automatically generated.\n')
   file.write('\n')
   file.write('#ifndef UI_GFX_GL_GL_BINDINGS_AUTOGEN_%s_H_\n' % set_name.upper())
@@ skipping 10 matching lines @@
       set_name.upper())
   file.write('void InitializeDebugGLBindings%s();\n' % set_name.upper())
 
   # Write typedefs for function pointer types. Always use the GL name for the
   # typedef.
   file.write('\n')
   for [return_type, names, arguments] in functions:
     file.write('typedef %s (GL_BINDING_CALL *%sProc)(%s);\n' %
         (return_type, names[0], arguments))
 
+  # Write declarations for booleans indicating which extensions are available.
+  file.write('\n')
+  for extension, ext_functions in used_extension_functions:
+    file.write('GL_EXPORT extern bool g_%s;\n' % extension)
+
   # Write declarations for function pointers. Always use the GL name for the
   # declaration.
   file.write('\n')
   for [return_type, names, arguments] in functions:
     file.write('GL_EXPORT extern %sProc g_%s;\n' % (names[0], names[0]))
   file.write('\n')
   file.write( '}  // namespace gfx\n')
 
   # Write macros to invoke function pointers. Always use the GL name for the
   # macro.
@@ skipping 14 matching lines @@
   file.write('// Copyright (c) 2011 The Chromium Authors. All rights reserved.\n')
   file.write('// Use of this source code is governed by a BSD-style license that can be\n')
   file.write('// found in the LICENSE file.\n')
   file.write('\n')
   file.write('// This file is automatically generated.\n')
   file.write('\n')
   file.write('#include "ui/gfx/gl/gl_bindings.h"\n')
   file.write('#include "ui/gfx/gl/gl_context.h"\n')
   file.write('#include "ui/gfx/gl/gl_implementation.h"\n')
 
-  # Write definitions of function pointers.
+  # Write definitions for booleans indicating which extensions are available.
   file.write('\n')
   file.write('namespace gfx {\n')
   file.write('\n')
+  for extension, ext_functions in used_extension_functions:
+    file.write('bool g_%s;\n' % extension)
+
+  # Write definitions of function pointers.
+  file.write('\n')
   file.write('static bool g_debugBindingsInitialized;\n')
   file.write('static void UpdateDebugGLExtensionBindings();\n')
   file.write('\n')
   for [return_type, names, arguments] in functions:
     file.write('%sProc g_%s;\n' % (names[0], names[0]))
 
   file.write('\n')
   for [return_type, names, arguments] in functions:
     file.write('static %sProc g_debug_%s;\n' % (names[0], names[0]))
 
@@ skipping 11 matching lines @@
               (names[0], names[0], name))
   file.write('}\n')
   file.write('\n')
 
   # Write function to initialize the extension function pointers. This function
   # uses a current context to query which extensions are actually supported.
   file.write('void InitializeGLExtensionBindings%s(GLContext* context) {\n' %
       set_name.upper())
   file.write('  DCHECK(context && context->IsCurrent(NULL));\n')
   for extension, ext_functions in used_extension_functions:
-    file.write('  if (context->HasExtension("%s")) {\n' % extension)
+    file.write('  if ((g_%s = context->HasExtension("%s"))) {\n' %
+        (extension, extension))
     queried_entry_points = set()
     for entry_point_name, function_name in ext_functions:
       # Replace the pointer unconditionally unless this extension has several
       # alternatives for the same entry point (e.g.,
       # GL_ARB_blend_func_extended).
       if entry_point_name in queried_entry_points:
         file.write('    if (!g_%s)\n  ' % entry_point_name)
       file.write(
          '    g_%s = reinterpret_cast<%sProc>(GetGLProcAddress("%s"));\n' %
              (entry_point_name, entry_point_name, function_name))
@@ skipping 239 matching lines @@
 
 def main(argv):
   """This is the main function."""
 
   if len(argv) >= 1:
     dir = argv[0]
   else:
     dir = '.'
 
   for [functions, set_name, extension_headers] in FUNCTION_SETS:
+    used_extension_functions = GetUsedExtensionFunctions(
+        functions, extension_headers)
+
     header_file = open(
         os.path.join(dir, 'gl_bindings_autogen_%s.h' % set_name), 'wb')
-    GenerateHeader(header_file, functions, set_name)
+    GenerateHeader(header_file, functions, set_name, used_extension_functions)
     header_file.close()
 
     source_file = open(
         os.path.join(dir, 'gl_bindings_autogen_%s.cc' % set_name), 'wb')
-    used_extension_functions = GetUsedExtensionFunctions(
-        functions, extension_headers)
     GenerateSource(source_file, functions, set_name, used_extension_functions)
     source_file.close()
 
   source_file = open(os.path.join(dir, 'gl_bindings_autogen_mock.cc'), 'wb')
   GenerateMockSource(source_file, GL_FUNCTIONS)
   source_file.close()
 
 
 if __name__ == '__main__':
   main(sys.argv[1:])