Revert of Remove code used by --disable-delegated-renderer on Mac

content/browser/renderer_host/compositing_iosurface_transformer_mac.cc

+// Copyright (c) 2013 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.
+
+#include "content/browser/renderer_host/compositing_iosurface_transformer_mac.h"
+
+#include <algorithm>
+
+#include "base/basictypes.h"
+#include "base/debug/trace_event.h"
+#include "base/logging.h"
+#include "content/browser/renderer_host/compositing_iosurface_shader_programs_mac.h"
+#include "ui/gfx/rect.h"
+#include "ui/gfx/size.h"
+
+namespace content {
+
+namespace {
+
+const GLenum kColorAttachments[] = {
+  GL_COLOR_ATTACHMENT0_EXT,
+  GL_COLOR_ATTACHMENT1_EXT
+};
+
+// Set viewport and model/projection matrices for drawing to a framebuffer of
+// size dst_size, with coordinates starting at (0, 0).
+void SetTransformationsForOffScreenRendering(const gfx::Size& dst_size) {
+  glViewport(0, 0, dst_size.width(), dst_size.height());
+  glMatrixMode(GL_PROJECTION);
+  glLoadIdentity();
+  glOrtho(0, dst_size.width(), 0, dst_size.height(), -1, 1);
+  glMatrixMode(GL_MODELVIEW);
+  glLoadIdentity();
+}
+
+// Configure texture sampling parameters.
+void SetTextureParameters(GLenum target, GLint min_mag_filter, GLint wrap) {
+  glTexParameteri(target, GL_TEXTURE_MIN_FILTER, min_mag_filter);
+  glTexParameteri(target, GL_TEXTURE_MAG_FILTER, min_mag_filter);
+  glTexParameteri(target, GL_TEXTURE_WRAP_S, wrap);
+  glTexParameteri(target, GL_TEXTURE_WRAP_T, wrap);
+}
+
+// Draw the currently-bound texture.  The src region is applied to the entire
+// destination framebuffer of the given size.  Specify |flip_y| is the src
+// texture is upside-down relative to the destination.
+//
+// Assumption: The orthographic projection is set up as
+// (0,0)x(dst_width,dst_height).
+void DrawQuad(float src_x, float src_y, float src_width, float src_height,
+              bool flip_y, float dst_width, float dst_height) {
+  glEnableClientState(GL_VERTEX_ARRAY);
+  glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+
+  float vertices[4][2] = {
+    { 0.0f, dst_height },
+    { 0.0f, 0.0f },
+    { dst_width, 0.0f },
+    { dst_width, dst_height }
+  };
+  glVertexPointer(arraysize(vertices[0]), GL_FLOAT, sizeof(vertices[0]),
+                  vertices);
+
+  float tex_coords[4][2] = {
+    { src_x, src_y + src_height },
+    { src_x, src_y },
+    { src_x + src_width, src_y },
+    { src_x + src_width, src_y + src_height }
+  };
+  if (flip_y) {
+    std::swap(tex_coords[0][1], tex_coords[1][1]);
+    std::swap(tex_coords[2][1], tex_coords[3][1]);
+  }
+  glTexCoordPointer(arraysize(tex_coords[0]), GL_FLOAT, sizeof(tex_coords[0]),
+                    tex_coords);
+
+  COMPILE_ASSERT(arraysize(vertices) == arraysize(tex_coords),
+                 same_number_of_points_in_both);
+  glDrawArrays(GL_QUADS, 0, arraysize(vertices));
+
+  glDisableClientState(GL_VERTEX_ARRAY);
+  glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+}
+
+}  // namespace
+
+CompositingIOSurfaceTransformer::CompositingIOSurfaceTransformer(
+    GLenum texture_target, bool src_texture_needs_y_flip,
+    CompositingIOSurfaceShaderPrograms* shader_program_cache)
+    : texture_target_(texture_target),
+      src_texture_needs_y_flip_(src_texture_needs_y_flip),
+      shader_program_cache_(shader_program_cache),
+      frame_buffer_(0) {
+  DCHECK(texture_target_ == GL_TEXTURE_RECTANGLE_ARB)
+      << "Fragment shaders currently only support RECTANGLE textures.";
+  DCHECK(shader_program_cache_);
+
+  memset(textures_, 0, sizeof(textures_));
+
+  // The RGB-to-YV12 transform requires that the driver/hardware supports
+  // multiple draw buffers.
+  GLint max_draw_buffers = 1;
+  glGetIntegerv(GL_MAX_DRAW_BUFFERS, &max_draw_buffers);
+  system_supports_multiple_draw_buffers_ = (max_draw_buffers >= 2);
+}
+
+CompositingIOSurfaceTransformer::~CompositingIOSurfaceTransformer() {
+  for (int i = 0; i < NUM_CACHED_TEXTURES; ++i)
+    DCHECK_EQ(textures_[i], 0u) << "Failed to call ReleaseCachedGLObjects().";
+  DCHECK_EQ(frame_buffer_, 0u) << "Failed to call ReleaseCachedGLObjects().";
+}
+
+void CompositingIOSurfaceTransformer::ReleaseCachedGLObjects() {
+  for (int i = 0; i < NUM_CACHED_TEXTURES; ++i) {
+    if (textures_[i]) {
+      glDeleteTextures(1, &textures_[i]);
+      textures_[i] = 0;
+      texture_sizes_[i] = gfx::Size();
+    }
+  }
+  if (frame_buffer_) {
+    glDeleteFramebuffersEXT(1, &frame_buffer_);
+    frame_buffer_ = 0;
+  }
+}
+
+bool CompositingIOSurfaceTransformer::ResizeBilinear(
+    GLuint src_texture, const gfx::Rect& src_subrect, const gfx::Size& dst_size,
+    GLuint* texture) {
+  if (src_subrect.IsEmpty() || dst_size.IsEmpty())
+    return false;
+
+  glActiveTexture(GL_TEXTURE0);
+  glDisable(GL_DEPTH_TEST);
+  glDisable(GL_BLEND);
+
+  PrepareTexture(RGBA_OUTPUT, dst_size);
+  PrepareFramebuffer();
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, frame_buffer_);
+  glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                            texture_target_, textures_[RGBA_OUTPUT], 0);
+  DCHECK(glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) ==
+             GL_FRAMEBUFFER_COMPLETE_EXT);
+
+  glBindTexture(texture_target_, src_texture);
+  SetTextureParameters(
+      texture_target_, src_subrect.size() == dst_size ? GL_NEAREST : GL_LINEAR,
+      GL_CLAMP_TO_EDGE);
+
+  const bool prepared = shader_program_cache_->UseBlitProgram();
+  DCHECK(prepared);
+  SetTransformationsForOffScreenRendering(dst_size);
+  DrawQuad(src_subrect.x(), src_subrect.y(),
+           src_subrect.width(), src_subrect.height(),
+           src_texture_needs_y_flip_,
+           dst_size.width(), dst_size.height());
+  glUseProgram(0);
+
+  glBindTexture(texture_target_, 0);
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+
+  *texture = textures_[RGBA_OUTPUT];
+  return true;
+}
+
+bool CompositingIOSurfaceTransformer::TransformRGBToYV12(
+    GLuint src_texture,
+    const gfx::Rect& src_subrect,
+    const gfx::Size& dst_size,
+    GLuint* texture_y,
+    GLuint* texture_u,
+    GLuint* texture_v,
+    gfx::Size* packed_y_size,
+    gfx::Size* packed_uv_size) {
+  if (!system_supports_multiple_draw_buffers_)
+    return false;
+  if (src_subrect.IsEmpty() || dst_size.IsEmpty())
+    return false;
+
+  TRACE_EVENT0("gpu", "TransformRGBToYV12");
+
+  glActiveTexture(GL_TEXTURE0);
+  glDisable(GL_DEPTH_TEST);
+  glDisable(GL_BLEND);
+
+  // Resize output textures for each plane, and for the intermediate UUVV one
+  // that becomes an input into pass #2.  |packed_y_size| is the size of the Y
+  // output texture, where its width is 1/4 the number of Y pixels because 4 Y
+  // pixels are packed into a single quad.  |packed_uv_size| is half the size of
+  // Y in both dimensions, rounded up.
+  *packed_y_size = gfx::Size((dst_size.width() + 3) / 4, dst_size.height());
+  *packed_uv_size = gfx::Size((packed_y_size->width() + 1) / 2,
+                              (packed_y_size->height() + 1) / 2);
+  PrepareTexture(Y_PLANE_OUTPUT, *packed_y_size);
+  PrepareTexture(UUVV_INTERMEDIATE, *packed_y_size);
+  PrepareTexture(U_PLANE_OUTPUT, *packed_uv_size);
+  PrepareTexture(V_PLANE_OUTPUT, *packed_uv_size);
+
+  /////////////////////////////////////////
+  // Pass 1: RGB --(scaled)--> YYYY + UUVV
+  PrepareFramebuffer();
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, frame_buffer_);
+  glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                            texture_target_, textures_[Y_PLANE_OUTPUT], 0);
+  glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT1_EXT,
+                            texture_target_, textures_[UUVV_INTERMEDIATE], 0);
+  DCHECK(glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) ==
+             GL_FRAMEBUFFER_COMPLETE_EXT);
+  glDrawBuffers(2, kColorAttachments);
+
+  // Read from |src_texture|.  Enable bilinear filtering only if scaling is
+  // required.  The filtering will take place entirely in the first pass.
+  glBindTexture(texture_target_, src_texture);
+  SetTextureParameters(
+      texture_target_, src_subrect.size() == dst_size ? GL_NEAREST : GL_LINEAR,
+      GL_CLAMP_TO_EDGE);
+
+  // Use the first-pass shader program and draw the scene.
+  const bool prepared_pass_1 = shader_program_cache_->UseRGBToYV12Program(
+      1,
+      static_cast<float>(src_subrect.width()) / dst_size.width());
+  DCHECK(prepared_pass_1);
+  SetTransformationsForOffScreenRendering(*packed_y_size);
+  DrawQuad(src_subrect.x(), src_subrect.y(),
+           ((packed_y_size->width() * 4.0f) / dst_size.width()) *
+               src_subrect.width(),
+           src_subrect.height(),
+           src_texture_needs_y_flip_,
+           packed_y_size->width(), packed_y_size->height());
+
+  /////////////////////////////////////////
+  // Pass 2: UUVV -> UUUU + VVVV
+  glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                            texture_target_, textures_[U_PLANE_OUTPUT], 0);
+  glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT1_EXT,
+                            texture_target_, textures_[V_PLANE_OUTPUT], 0);
+  DCHECK(glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) ==
+             GL_FRAMEBUFFER_COMPLETE_EXT);
+
+  // Read from the intermediate UUVV texture.  The second pass uses bilinear
+  // minification to achieve vertical scaling, so enable it always.
+  glBindTexture(texture_target_, textures_[UUVV_INTERMEDIATE]);
+  SetTextureParameters(texture_target_, GL_LINEAR, GL_CLAMP_TO_EDGE);
+
+  // Use the second-pass shader program and draw the scene.
+  const bool prepared_pass_2 =
+      shader_program_cache_->UseRGBToYV12Program(2, 1.0f);
+  DCHECK(prepared_pass_2);
+  SetTransformationsForOffScreenRendering(*packed_uv_size);
+  DrawQuad(0.0f, 0.0f,
+           packed_uv_size->width() * 2.0f,
+           packed_uv_size->height() * 2.0f,
+           false,
+           packed_uv_size->width(), packed_uv_size->height());
+  glUseProgram(0);
+
+  // Before leaving, put back to drawing to a single rendering output.
+  glDrawBuffers(1, kColorAttachments);
+
+  glBindTexture(texture_target_, 0);
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+
+  *texture_y = textures_[Y_PLANE_OUTPUT];
+  *texture_u = textures_[U_PLANE_OUTPUT];
+  *texture_v = textures_[V_PLANE_OUTPUT];
+  return true;
+}
+
+void CompositingIOSurfaceTransformer::PrepareTexture(
+    CachedTexture which, const gfx::Size& size) {
+  DCHECK_GE(which, 0);
+  DCHECK_LT(which, NUM_CACHED_TEXTURES);
+  DCHECK(!size.IsEmpty());
+
+  if (!textures_[which]) {
+    glGenTextures(1, &textures_[which]);
+    DCHECK_NE(textures_[which], 0u);
+    texture_sizes_[which] = gfx::Size();
+  }
+
+  // Re-allocate the texture if its size has changed since last use.
+  if (texture_sizes_[which] != size) {
+    TRACE_EVENT2("gpu", "Resize Texture",
+                 "which", which,
+                 "new_size", size.ToString());
+    glBindTexture(texture_target_, textures_[which]);
+    glTexImage2D(texture_target_, 0, GL_RGBA, size.width(), size.height(), 0,
+                 GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, NULL);
+    texture_sizes_[which] = size;
+  }
+}
+
+void CompositingIOSurfaceTransformer::PrepareFramebuffer() {
+  if (!frame_buffer_) {
+    glGenFramebuffersEXT(1, &frame_buffer_);
+    DCHECK_NE(frame_buffer_, 0u);
+  }
+}
+
+}  // namespace content