Surfaceless OutputSurface implementation.

content/browser/compositor/buffered_output_surface.cc

+// Copyright 2014 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/compositor/buffered_output_surface.h"
+
+#include "content/common/gpu/client/context_provider_command_buffer.h"
+#include "gpu/GLES2/gl2extchromium.h"
+#include "gpu/command_buffer/client/gles2_interface.h"
+
+namespace content {
+
+BufferedOutputSurface::BufferedOutputSurface(
+    scoped_refptr<cc::ContextProvider> context_provider,
+    unsigned int internalformat)
+    : context_provider_(context_provider),
+      fbo_(0),
+      depth_rb_(0),
+      allocated_count_(0),
+      internalformat_(internalformat) {
+  Initialize();
+}
+
+BufferedOutputSurface::~BufferedOutputSurface() {
+  FreeAllSurfaces();
+
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  if (fbo_)
+    gl->DeleteFramebuffers(1, &fbo_);
+  if (depth_rb_)
+    gl->DeleteRenderbuffers(1, &depth_rb_);
+}
+
+void BufferedOutputSurface::Initialize() {
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  gl->GenFramebuffers(1, &fbo_);
+  gl->GenRenderbuffers(1, &depth_rb_);
+  DCHECK(fbo_);
+  DCHECK(depth_rb_);
+}
+
+void BufferedOutputSurface::BindFramebuffer() {
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  gl->BindFramebuffer(GL_FRAMEBUFFER, fbo_);
+
+  if (!current_surface_.first) {
+    current_surface_ = GetNextSurface();
+    gl->FramebufferTexture2D(GL_FRAMEBUFFER,
+                             GL_COLOR_ATTACHMENT0,
+                             GL_TEXTURE_2D,
+                             current_surface_.second,
+                             0);
+  }
+}
+
+void BufferedOutputSurface::SwapBuffers() {
+  if (last_surface_.first)
+    in_flight_surfaces_.push(last_surface_);
+  last_surface_ = current_surface_;
+  current_surface_.first = 0;
+  current_surface_.second = 0;
+}
+
+void BufferedOutputSurface::Reshape(const gfx::Size& size, float scale_factor) {
+  if (size == size_)
+    return;
+  size_ = size;
+  FreeAllSurfaces();
+
+  if (size_.width() == 0 || size_.height() == 0)
+    return;  // Nothing to do.
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  gl->BindFramebuffer(GL_FRAMEBUFFER, fbo_);
+  gl->BindRenderbuffer(GL_RENDERBUFFER, depth_rb_);
+  gl->RenderbufferStorage(
+      GL_RENDERBUFFER, GL_DEPTH_COMPONENT24_OES, size_.width(), size_.height());
+  gl->FramebufferRenderbuffer(
+      GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depth_rb_);
+}
+
+void BufferedOutputSurface::PageFlipComplete() {
+  if (!in_flight_surfaces_.empty()) {
+    available_surfaces_.push_back(in_flight_surfaces_.front());
+    in_flight_surfaces_.pop();
+  }
+}
+
+void BufferedOutputSurface::FreeAllSurfaces() {
+  FreeSurface(&last_surface_);
+  FreeSurface(&current_surface_);
+  while (!in_flight_surfaces_.empty()) {
+    FreeSurface(&in_flight_surfaces_.front());
+    in_flight_surfaces_.pop();
+  }
+  for (size_t i = 0; i < available_surfaces_.size(); i++)
+    FreeSurface(&available_surfaces_[i]);
+  available_surfaces_.clear();
+}
+
+void BufferedOutputSurface::FreeSurface(AllocatedSurface* surface) {
+  if (surface->first) {
+    gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+    gl->DeleteTextures(1, &surface->first);

[alexst (slow to review), 2014/09/10 21:25:14]

Use ReleaseTexImage2DCHROMIUM before deleting the texture please

[achaulk, 2014/09/11 17:25:47]

Done.

+    gl->DestroyImageCHROMIUM(surface->second);
+    surface->first = 0;
+    surface->second = 0;
+  }
+}
+
+BufferedOutputSurface::AllocatedSurface
+BufferedOutputSurface::GetNextSurface() {
+  if (!available_surfaces_.empty()) {
+    AllocatedSurface id = available_surfaces_.back();
+    available_surfaces_.pop_back();
+    return id;
+  }
+
+  unsigned int tex;
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  gl->GenTextures(1, &tex);
+
+  // We don't want to allow anything more than triple buffering.
+  DCHECK(allocated_count_ < 4);

[alexst (slow to review), 2014/09/10 21:25:14]

There is a DCHECK_LT, please use that instead.

[achaulk, 2014/09/11 17:25:48]

Done.

+
+  unsigned int id = context_provider_->ContextGL()->CreateImageCHROMIUM(
+      size_.width(),
+      size_.height(),
+      internalformat_,
+      GL_IMAGE_SCANOUT_CHROMIUM);
+  DCHECK(id);
+  allocated_count_++;
+  gl->BindTexture(GL_TEXTURE_2D, tex);
+  gl->BindTexImage2DCHROMIUM(GL_TEXTURE_2D, id);
+  return AllocatedSurface(tex, id);
+}
+
+}  // namespace content