ui/gl/scoped_binders.cc

   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 #include "ui/gl/scoped_binders.h"
   6 #include "ui/gl/gl_bindings.h"
   7 #include "ui/gl/gl_context.h"
   8 #include "ui/gl/gl_state_restorer.h"
   9
  10 namespace gfx {
  11
  12 ScopedFrameBufferBinder::ScopedFrameBufferBinder(unsigned int fbo)
  13     : state_restorer_(!GLContext::GetCurrent()
  14                           ? NULL
  15                           : GLContext::GetCurrent()->GetGLStateRestorer()),
  16       old_fbo_(-1) {
  17   if (!state_restorer_)
  18     glGetIntegerv(GL_FRAMEBUFFER_BINDING, &old_fbo_);
  19   glBindFramebufferEXT(GL_FRAMEBUFFER, fbo);
  20 }
  21
  22 ScopedFrameBufferBinder::~ScopedFrameBufferBinder() {
  23   if (state_restorer_) {
  24     DCHECK(!!GLContext::GetCurrent());
  25     DCHECK_EQ(state_restorer_, GLContext::GetCurrent()->GetGLStateRestorer());
  26     state_restorer_->RestoreFramebufferBindings();
  27   } else {
  28     glBindFramebufferEXT(GL_FRAMEBUFFER, old_fbo_);
  29   }
  30 }
  31
  32 ScopedTextureBinder::ScopedTextureBinder(unsigned int target, unsigned int id)
  33     : state_restorer_(!GLContext::GetCurrent()
  34                           ? NULL
  35                           : GLContext::GetCurrent()->GetGLStateRestorer()),
  36       target_(target),
  37       old_id_(-1) {
  38   if (!state_restorer_) {
  39     GLenum target_getter = 0;
  40     switch (target) {
  41       case GL_TEXTURE_2D:
  42         target_getter = GL_TEXTURE_BINDING_2D;
  43         break;
  44       case GL_TEXTURE_CUBE_MAP:
  45         target_getter = GL_TEXTURE_BINDING_CUBE_MAP;
  46         break;
  47       case GL_TEXTURE_EXTERNAL_OES:
  48         target_getter = GL_TEXTURE_BINDING_EXTERNAL_OES;
  49         break;
  50       default:
  51         NOTIMPLEMENTED() << "Target not part of OpenGL ES 2.0 spec.";
  52     }
  53     glGetIntegerv(target_getter, &old_id_);
  54   }
  55   glBindTexture(target_, id);
  56 }
  57
  58 ScopedTextureBinder::~ScopedTextureBinder() {
  59   if (state_restorer_) {
  60     DCHECK(!!GLContext::GetCurrent());
  61     DCHECK_EQ(state_restorer_, GLContext::GetCurrent()->GetGLStateRestorer());
  62     state_restorer_->RestoreActiveTextureUnitBinding(target_);
  63   } else {
  64     glBindTexture(target_, old_id_);
  65   }
  66 }
  67
  68 }  // namespace gfx