Initial checkin of the compositor_model_bench tool, which simulates the GPU demands of Chromium's...

gpu/tools/compositor_model_bench/forward_render_model.cc

+// Copyright (c) 2011 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 "gpu/tools/compositor_model_bench/forward_render_model.h"
+
+#include <cstdlib>
+#include <vector>
+
+#include "gpu/tools/compositor_model_bench/render_model_utils.h"
+
+using std::vector;
+
+class ForwardRenderNodeVisitor : public RenderNodeVisitor {
+ public:
+  ForwardRenderNodeVisitor() {}
+
+  virtual void BeginVisitRenderNode(RenderNode* v) OVERRIDE {
+    NOTREACHED();
+  }
+
+  virtual void BeginVisitCCNode(CCNode* v) OVERRIDE {
+    if (!v->drawsContent())
+      return;
+    ConfigAndActivateShaderForNode(v);
+    DrawQuad(v->width(), v->height());
+  }
+
+  virtual void BeginVisitContentLayerNode(ContentLayerNode* l) OVERRIDE {
+    if (!l->drawsContent())
+      return;
+    ConfigAndActivateShaderForTiling(l);
+    // Now that we capture root layer tiles, a layer without tiles
+    // should not get drawn.
+    for (size_t n = 0; n < l->num_tiles(); ++n) {
+      const Tile* i = l->tile(n);
+      DrawTileQuad(i->texID, i->x, i->y);
+    }
+  }
+};
+
+ForwardRenderSimulator::ForwardRenderSimulator(RenderNode* root,
+                                               int window_width,
+                                               int window_height)
+    : RenderModelSimulator(root) {
+  textures_.reset(new TextureGenerator(root));
+  visitor_.reset(new ForwardRenderNodeVisitor());
+  glViewport(0, 0, window_width, window_height);
+  glDisable(GL_DEPTH_TEST);
+  glDisable(GL_CULL_FACE);
+  glEnable(GL_BLEND);
+  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+}
+
+ForwardRenderSimulator::~ForwardRenderSimulator() OVERRIDE {
+  delete visitor_;
+}
+
+void ForwardRenderSimulator::Update() OVERRIDE {
+  glClearColor(0, 0, 1, 1);
+  glColorMask(true, true, true, true);
+  glClear(GL_COLOR_BUFFER_BIT);
+  glColorMask(true, true, true, false);
+  BeginFrame();
+  root_->Accept(visitor_);
+}
+
+void ForwardRenderSimulator::Resize(int width, int height) OVERRIDE {
+  glViewport(0, 0, width, height);
+}
+