Add a simple compositor for Sky

sky/compositor/layer_host.cc

Index: sky/compositor/layer_host.cc
diff --git a/sky/compositor/layer_host.cc b/sky/compositor/layer_host.cc
new file mode 100644
index 0000000000000000000000000000000000000000..2cd2de038c4bc98ffc07d13f47104f4305d50ba5
--- /dev/null
+++ b/sky/compositor/layer_host.cc
@@ -0,0 +1,101 @@
+// 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 "sky/compositor/layer_host.h"
+
+#include "mojo/converters/geometry/geometry_type_converters.h"
+#include "mojo/gpu/gl_context.h"
+#include "mojo/services/public/cpp/surfaces/surfaces_utils.h"
+#include "mojo/skia/ganesh_context.h"
+#include "sky/compositor/layer.h"
+
+namespace sky {
+
+LayerHost::LayerHost(LayerHostClient* client)
+    : client_(client),
+      surface_holder_(this, client->GetShell()),
+      gl_context_(mojo::GLContext::Create(client->GetShell())),
+      ganesh_context_(gl_context_),
+      resource_manager_(gl_context_) {
+}
+
+LayerHost::~LayerHost() {
+}
+
+void LayerHost::SetNeedsAnimate() {
+}
+
+void LayerHost::SetRootLayer(scoped_refptr<Layer> layer) {
+  DCHECK(!root_layer_.get());
+  root_layer_ = layer;
+  root_layer_->set_host(this);
+}
+
+void LayerHost::OnReadyForNextFrame() {
+  client_->BeginFrame();
+  root_layer_->Display();
+  Upload(root_layer_.get());
+}
+
+void LayerHost::OnSurfaceIdAvailable(mojo::SurfaceIdPtr surface_id) {
+  client_->OnSurfaceIdAvailable(surface_id.Pass());
+}
+
+void LayerHost::ReturnResources(
+    mojo::Array<mojo::ReturnedResourcePtr> resources) {
+  resource_manager_.ReturnResources(resources.Pass());
+}
+
+void LayerHost::Upload(Layer* layer) {
+  gfx::Size size = layer->size();
+  surface_holder_.SetSize(size);
+
+  mojo::FramePtr frame = mojo::Frame::New();
+  frame->resources.resize(0u);
+
+  mojo::Rect bounds;
+  bounds.width = size.width();
+  bounds.height = size.height();
+  mojo::PassPtr pass = mojo::CreateDefaultPass(1, bounds);
+  pass->quads.resize(0u);
+  pass->shared_quad_states.push_back(mojo::CreateDefaultSQS(
+      mojo::TypeConverter<mojo::Size, gfx::Size>::Convert(size)));
+
+  mojo::TransferableResourcePtr resource =
+      resource_manager_.CreateTransferableResource(layer);
+
+  mojo::QuadPtr quad = mojo::Quad::New();
+  quad->material = mojo::MATERIAL_TEXTURE_CONTENT;
+
+  mojo::RectPtr rect = mojo::Rect::New();
+  rect->width = size.width();
+  rect->height = size.height();
+  quad->rect = rect.Clone();
+  quad->opaque_rect = rect.Clone();
+  quad->visible_rect = rect.Clone();
+  quad->needs_blending = true;
+  quad->shared_quad_state_index = 0u;
+
+  mojo::TextureQuadStatePtr texture_state = mojo::TextureQuadState::New();
+  texture_state->resource_id = resource->id;
+  texture_state->premultiplied_alpha = true;
+  texture_state->uv_top_left = mojo::PointF::New();
+  texture_state->uv_bottom_right = mojo::PointF::New();
+  texture_state->uv_bottom_right->x = 1.f;
+  texture_state->uv_bottom_right->y = 1.f;
+  texture_state->background_color = mojo::Color::New();
+  texture_state->background_color->rgba = 0;
+  for (int i = 0; i < 4; ++i)
+    texture_state->vertex_opacity.push_back(1.f);
+  texture_state->flipped = false;
+
+  frame->resources.push_back(resource.Pass());
+  quad->texture_quad_state = texture_state.Pass();
+  pass->quads.push_back(quad.Pass());
+
+  frame->passes.push_back(pass.Pass());
+  surface_holder_.SubmitFrame(frame.Pass());
+}
+
+}  // namespace sky