Initial checkin of the new Mozart compositor.

services/gfx/compositor/graph/scene_def.h

+// Copyright 2015 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.
+
+#ifndef SERVICES_GFX_COMPOSITOR_GRAPH_SCENE_DEF_H_
+#define SERVICES_GFX_COMPOSITOR_GRAPH_SCENE_DEF_H_
+
+#include <iosfwd>
+#include <memory>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "mojo/services/gfx/composition/interfaces/scenes.mojom.h"
+#include "services/gfx/compositor/graph/node_def.h"
+
+namespace compositor {
+
+class RenderLayer;
+class RenderLayerBuilder;
+class SceneDef;
+class SnapshotBuilder;
+
+// Resolves a scene token to a scene definition.
+using SceneResolver =
+    base::Callback<SceneDef*(mojo::gfx::composition::SceneToken*)>;
+
+// Sends a scene unavailable message with the specified resource id.
+using SceneUnavailableSender = base::Callback<void(uint32_t)>;
+
+// Scene definition.
+// Contains all of the resources and nodes of a published scene.
+class SceneDef {
+ public:
+  // Outcome of a call to |Present|.
+  enum class Disposition {
+    kUnchanged,
+    kSucceeded,
+    kFailed,
+  };
+
+  SceneDef(mojo::gfx::composition::SceneTokenPtr scene_token,
+           const std::string& label);
+  ~SceneDef();
+
+  // Gets the token used to refer to this scene globally.
+  // Caller does not obtain ownership of the token.
+  mojo::gfx::composition::SceneToken* scene_token() {
+    return scene_token_.get();
+  }
+
+  // Gets the currently published scene graph version.
+  uint32_t version() { return version_; }
+
+  // Gets the root node, or nullptr if none.
+  NodeDef* root_node() { return root_node_; }
+
+  // Enqueues a pending update event to the scene graph.
+  void EnqueueUpdate(mojo::gfx::composition::SceneUpdatePtr update);
+
+  // Enqueues a pending publish event to the scene graph.
+  // The changes are not applied until |ApplyChanges| is called.
+  void EnqueuePublish(mojo::gfx::composition::SceneMetadataPtr metadata);
+
+  // Applies published updates to the scene up to the point indicated by
+  // |presentation_time|.
+  //
+  // Returns a value which indicates whether the updates succeded.
+  // If the result is |kFailed|, the scene graph was left in an unusable
+  // and inconsistent state and must be destroyed.
+  Disposition Present(int64_t presentation_time,
+                      const SceneResolver& resolver,
+                      const SceneUnavailableSender& unavailable_sender,
+                      std::ostream& err);
+
+  // Unlinks references to another scene which has been unregistered.
+  // Causes |OnResourceUnavailable()| to be delivered to the scene for all
+  // invalidated scene resources.  Returns true if any changes were made.
+  bool UnlinkReferencedScene(SceneDef* scene,
+                             const SceneUnavailableSender& unavailable_sender);
+
+  // Generates a snapshot of the scene.
+  // Returns true if successful, false if the scene is blocked from rendering.
+  bool Snapshot(SnapshotBuilder* snapshot_builder,
+                RenderLayerBuilder* layer_builder);
+
+  // Finds the resource with the specified id.
+  // Returns nullptr if not found.
+  ResourceDef* FindResource(uint32_t resource_id,
+                            ResourceDef::Type resource_type);
+  SceneResourceDef* FindSceneResource(uint32_t scene_resource_id) {
+    return static_cast<SceneResourceDef*>(
+        FindResource(scene_resource_id, ResourceDef::Type::kScene));
+  }
+  ImageResourceDef* FindImageResource(uint32_t image_resource_id) {
+    return static_cast<ImageResourceDef*>(
+        FindResource(image_resource_id, ResourceDef::Type::kImage));
+  }
+
+  // Finds the node with the specified id.
+  // Returns nullptr if not found.
+  NodeDef* FindNode(uint32_t node_id);
+
+  const std::string& label() { return label_; }
+  std::string FormattedLabel();
+
+ private:
+  struct Publication {
+    Publication(mojo::gfx::composition::SceneMetadataPtr metadata);
+    ~Publication();
+
+    bool is_due(int64_t presentation_time) const {
+      return metadata->presentation_time <= presentation_time;
+    }
+
+    mojo::gfx::composition::SceneMetadataPtr metadata;
+    std::vector<mojo::gfx::composition::SceneUpdatePtr> updates;
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Publication);
+  };
+
+  bool ApplyUpdate(mojo::gfx::composition::SceneUpdatePtr update,
+                   const SceneResolver& resolver,
+                   const SceneUnavailableSender& unavailable_sender,
+                   std::ostream& err);
+  bool Validate(std::ostream& err);
+
+  bool SnapshotInner(SnapshotBuilder* snapshot_builder,
+                     RenderLayerBuilder* layer_builder);
+  std::shared_ptr<RenderLayer> SnapshotLayer(SnapshotBuilder* snapshot_builder);
+  void Invalidate();
+  bool HasSceneResources();
+
+  ResourceDef* CreateResource(uint32_t resource_id,
+                              mojo::gfx::composition::ResourcePtr resource_decl,
+                              const SceneResolver& resolver,
+                              const SceneUnavailableSender& unavailable_sender,
+                              std::ostream& err);
+  NodeDef* CreateNode(uint32_t node_id,
+                      mojo::gfx::composition::NodePtr node_decl,
+                      std::ostream& err);
+  NodeOp* CreateNodeOp(uint32_t node_id,
+                       mojo::gfx::composition::NodeOpPtr node_op_decl,
+                       std::ostream& err);
+
+  mojo::gfx::composition::SceneTokenPtr scene_token_;
+  const std::string label_;
+  std::string formatted_label_cache_;
+
+  uint32_t version_ = mojo::gfx::composition::kSceneVersionNone;
+  std::vector<mojo::gfx::composition::SceneUpdatePtr> pending_updates_;
+  std::vector<std::unique_ptr<Publication>> pending_publications_;
+  std::unordered_map<uint32_t, std::unique_ptr<ResourceDef>> resources_;
+  std::unordered_map<uint32_t, std::unique_ptr<NodeDef>> nodes_;
+  NodeDef* root_node_ = nullptr;
+
+  std::shared_ptr<RenderLayer> cached_layer_;
+
+  // Used to detect cycles during a snapshot operation.
+  // This is safe because the object will only be used by a single thread.
+  bool visited_ = false;
+
+  DISALLOW_COPY_AND_ASSIGN(SceneDef);
+};
+
+}  // namespace compositor
+
+#endif  // SERVICES_GFX_COMPOSITOR_GRAPH_SCENE_DEF_H_