gl_helper.h revision c2e0dbddbe15c98d52c4786dac06cb8952a8ae6d 
1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_
6#define CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_
7
8#include "base/atomicops.h"
9#include "base/basictypes.h"
10#include "base/callback.h"
11#include "base/memory/scoped_ptr.h"
12#include "content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h"
13
14namespace gfx {
15class Rect;
16class Size;
17}
18
19class SkRegion;
20
21namespace content {
22
23// Provides higher level operations on top of the WebKit::WebGraphicsContext3D
24// interfaces.
25class GLHelper {
26 public:
27  explicit GLHelper(WebGraphicsContext3DCommandBufferImpl* context);
28  virtual ~GLHelper();
29
30  WebGraphicsContext3DCommandBufferImpl* context() const;
31
32  // Copies the block of pixels specified with |src_subrect| from |src_texture|,
33  // scales it to |dst_size|, and writes it into |out|.
34  // |src_size| is the size of |src_texture|. The result is of format GL_BGRA
35  // and is potentially flipped vertically to make it a correct image
36  // representation.  |callback| is invoked with the copy result when the copy
37  // operation has completed.
38  void CropScaleReadbackAndCleanTexture(
39      WebKit::WebGLId src_texture,
40      const gfx::Size& src_size,
41      const gfx::Rect& src_subrect,
42      const gfx::Size& dst_size,
43      unsigned char* out,
44      const base::Callback<void(bool)>& callback);
45
46  // Copies the texture data out of |texture| into |out|.  |size| is the
47  // size of the texture.  No post processing is applied to the pixels.  The
48  // texture is assumed to have a format of GL_RGBA with a pixel type of
49  // GL_UNSIGNED_BYTE.  This is a blocking call that calls glReadPixels on this
50  // current context.
51  void ReadbackTextureSync(WebKit::WebGLId texture,
52                           const gfx::Rect& src_rect,
53                           unsigned char* out);
54
55  // Creates a copy of the specified texture. |size| is the size of the texture.
56  WebKit::WebGLId CopyTexture(WebKit::WebGLId texture,
57                              const gfx::Size& size);
58
59  // Creates a scaled copy of the specified texture. |src_size| is the size of
60  // the texture and |dst_size| is the size of the resulting copy.
61  WebKit::WebGLId CopyAndScaleTexture(WebKit::WebGLId texture,
62                                      const gfx::Size& src_size,
63                                      const gfx::Size& dst_size,
64                                      bool vertically_flip_texture);
65
66  // Returns the shader compiled from the source.
67  WebKit::WebGLId CompileShaderFromSource(const WebKit::WGC3Dchar* source,
68                                          WebKit::WGC3Denum type);
69
70  // Copies all pixels from |previous_texture| into |texture| that are
71  // inside the region covered by |old_damage| but not part of |new_damage|.
72  void CopySubBufferDamage(WebKit::WebGLId texture,
73                           WebKit::WebGLId previous_texture,
74                           const SkRegion& new_damage,
75                           const SkRegion& old_damage);
76
77 private:
78  class CopyTextureToImpl;
79
80  // Creates |copy_texture_to_impl_| if NULL.
81  void InitCopyTextToImpl();
82
83  WebGraphicsContext3DCommandBufferImpl* context_;
84  scoped_ptr<CopyTextureToImpl> copy_texture_to_impl_;
85
86  DISALLOW_COPY_AND_ASSIGN(GLHelper);
87};
88
89}  // namespace content
90
91#endif  // CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_
92