cc/texture_copier.cc

   1 // Copyright 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 "cc/texture_copier.h"
   6
   7 #include "base/debug/trace_event.h"
   8 #include "build/build_config.h"
   9 #include "cc/gl_renderer.h" // For the GLC() macro.
  10 #include "third_party/khronos/GLES2/gl2.h"
  11 #include <public/WebGraphicsContext3D.h>
  12
  13 namespace cc {
  14
  15 AcceleratedTextureCopier::AcceleratedTextureCopier(WebKit::WebGraphicsContext3D* context, bool usingBindUniforms)
  16     : m_context(context)
  17     , m_usingBindUniforms(usingBindUniforms)
  18 {
  19     DCHECK(m_context);
  20     GLC(m_context, m_fbo = m_context->createFramebuffer());
  21     GLC(m_context, m_positionBuffer = m_context->createBuffer());
  22
  23     static const float kPositions[4][4] = {
  24         {-1, -1, 0, 1},
  25         { 1, -1, 0, 1},
  26         { 1, 1, 0, 1},
  27         {-1, 1, 0, 1}
  28     };
  29
  30     GLC(m_context, m_context->bindBuffer(GL_ARRAY_BUFFER, m_positionBuffer));
  31     GLC(m_context, m_context->bufferData(GL_ARRAY_BUFFER, sizeof(kPositions), kPositions, GL_STATIC_DRAW));
  32     GLC(m_context, m_context->bindBuffer(GL_ARRAY_BUFFER, 0));
  33
  34     m_blitProgram.reset(new BlitProgram(m_context));
  35 }
  36
  37 AcceleratedTextureCopier::~AcceleratedTextureCopier()
  38 {
  39     if (m_blitProgram)
  40         m_blitProgram->cleanup(m_context);
  41     if (m_positionBuffer)
  42         GLC(m_context, m_context->deleteBuffer(m_positionBuffer));
  43     if (m_fbo)
  44         GLC(m_context, m_context->deleteFramebuffer(m_fbo));
  45 }
  46
  47 void AcceleratedTextureCopier::copyTexture(Parameters parameters)
  48 {
  49     TRACE_EVENT0("cc", "TextureCopier::copyTexture");
  50
  51     GLC(m_context, m_context->disable(GL_SCISSOR_TEST));
  52
  53     // Note: this code does not restore the viewport, bound program, 2D texture, framebuffer, buffer or blend enable.
  54     GLC(m_context, m_context->bindFramebuffer(GL_FRAMEBUFFER, m_fbo));
  55     GLC(m_context, m_context->framebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, parameters.destTexture, 0));
  56
  57 #if defined(OS_ANDROID)
  58     // Clear destination to improve performance on tiling GPUs.
  59     // TODO: Use EXT_discard_framebuffer or skip clearing if it isn't available.
  60     GLC(m_context, m_context->clear(GL_COLOR_BUFFER_BIT));
  61 #endif
  62
  63     GLC(m_context, m_context->bindTexture(GL_TEXTURE_2D, parameters.sourceTexture));
  64     GLC(m_context, m_context->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST));
  65     GLC(m_context, m_context->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST));
  66
  67     if (!m_blitProgram->initialized())
  68         m_blitProgram->initialize(m_context, m_usingBindUniforms);
  69
  70     // TODO: Use EXT_framebuffer_blit if available.
  71     GLC(m_context, m_context->useProgram(m_blitProgram->program()));
  72
  73     const int kPositionAttribute = 0;
  74     GLC(m_context, m_context->bindBuffer(GL_ARRAY_BUFFER, m_positionBuffer));
  75     GLC(m_context, m_context->vertexAttribPointer(kPositionAttribute, 4, GL_FLOAT, false, 0, 0));
  76     GLC(m_context, m_context->enableVertexAttribArray(kPositionAttribute));
  77     GLC(m_context, m_context->bindBuffer(GL_ARRAY_BUFFER, 0));
  78
  79     GLC(m_context, m_context->viewport(0, 0, parameters.size.width(), parameters.size.height()));
  80     GLC(m_context, m_context->disable(GL_BLEND));
  81     GLC(m_context, m_context->drawArrays(GL_TRIANGLE_FAN, 0, 4));
  82
  83     GLC(m_context, m_context->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
  84     GLC(m_context, m_context->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
  85     GLC(m_context, m_context->disableVertexAttribArray(kPositionAttribute));
  86
  87     GLC(m_context, m_context->useProgram(0));
  88
  89     GLC(m_context, m_context->framebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0));
  90     GLC(m_context, m_context->bindFramebuffer(GL_FRAMEBUFFER, 0));
  91     GLC(m_context, m_context->bindTexture(GL_TEXTURE_2D, 0));
  92
  93     GLC(m_context, m_context->enable(GL_SCISSOR_TEST));
  94 }
  95
  96 void AcceleratedTextureCopier::flush()
  97 {
  98     GLC(m_context, m_context->flush());
  99 }
 100
 101 }  // namespace cc