compositor.h revision a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7
1// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef UI_COMPOSITOR_COMPOSITOR_H_ 6#define UI_COMPOSITOR_COMPOSITOR_H_ 7 8#include <string> 9 10#include "base/containers/hash_tables.h" 11#include "base/memory/ref_counted.h" 12#include "base/memory/scoped_ptr.h" 13#include "base/observer_list.h" 14#include "base/time/time.h" 15#include "cc/trees/layer_tree_host_client.h" 16#include "cc/trees/layer_tree_host_single_thread_client.h" 17#include "third_party/skia/include/core/SkColor.h" 18#include "ui/compositor/compositor_export.h" 19#include "ui/compositor/compositor_observer.h" 20#include "ui/gfx/native_widget_types.h" 21#include "ui/gfx/size.h" 22#include "ui/gfx/vector2d.h" 23 24class SkBitmap; 25 26namespace base { 27class MessageLoopProxy; 28class RunLoop; 29} 30 31namespace blink { 32class WebGraphicsContext3D; 33} 34 35namespace cc { 36class ContextProvider; 37class Layer; 38class LayerTreeDebugState; 39class LayerTreeHost; 40} 41 42namespace gfx { 43class Rect; 44class Size; 45} 46 47namespace ui { 48 49class Compositor; 50class Layer; 51class PostedSwapQueue; 52class Reflector; 53class Texture; 54struct LatencyInfo; 55 56// This class abstracts the creation of the 3D context for the compositor. It is 57// a global object. 58class COMPOSITOR_EXPORT ContextFactory { 59 public: 60 virtual ~ContextFactory() {} 61 62 // Gets the global instance. 63 static ContextFactory* GetInstance(); 64 65 // Sets the global instance. Caller keeps ownership. 66 // If this function isn't called (for tests), a "default" factory will be 67 // created on the first call of GetInstance. 68 static void SetInstance(ContextFactory* instance); 69 70 // Creates an output surface for the given compositor. The factory may keep 71 // per-compositor data (e.g. a shared context), that needs to be cleaned up 72 // by calling RemoveCompositor when the compositor gets destroyed. 73 virtual scoped_ptr<cc::OutputSurface> CreateOutputSurface( 74 Compositor* compositor, bool software_fallback) = 0; 75 76 // Creates a reflector that copies the content of the |mirrored_compositor| 77 // onto |mirroing_layer|. 78 virtual scoped_refptr<Reflector> CreateReflector( 79 Compositor* mirrored_compositor, 80 Layer* mirroring_layer) = 0; 81 // Removes the reflector, which stops the mirroring. 82 virtual void RemoveReflector(scoped_refptr<Reflector> reflector) = 0; 83 84 // Returns a reference to the offscreen context provider used by the 85 // compositor. This provider is bound and used on whichever thread the 86 // compositor is rendering from. 87 virtual scoped_refptr<cc::ContextProvider> 88 OffscreenCompositorContextProvider() = 0; 89 90 // Return a reference to a shared offscreen context provider usable from the 91 // main thread. This may be the same as OffscreenCompositorContextProvider() 92 // depending on the compositor's threading configuration. This provider will 93 // be bound to the main thread. 94 virtual scoped_refptr<cc::ContextProvider> 95 SharedMainThreadContextProvider() = 0; 96 97 // Destroys per-compositor data. 98 virtual void RemoveCompositor(Compositor* compositor) = 0; 99 100 // When true, the factory uses test contexts that do not do real GL 101 // operations. 102 virtual bool DoesCreateTestContexts() = 0; 103}; 104 105// Texture provide an abstraction over the external texture that can be passed 106// to a layer. 107class COMPOSITOR_EXPORT Texture : public base::RefCounted<Texture> { 108 public: 109 Texture(bool flipped, const gfx::Size& size, float device_scale_factor); 110 111 bool flipped() const { return flipped_; } 112 gfx::Size size() const { return size_; } 113 float device_scale_factor() const { return device_scale_factor_; } 114 115 virtual unsigned int PrepareTexture() = 0; 116 virtual blink::WebGraphicsContext3D* HostContext3D() = 0; 117 118 // Replaces the texture with the texture from the specified mailbox. 119 virtual void Consume(const std::string& mailbox_name, 120 const gfx::Size& new_size) {} 121 122 // Moves the texture into the mailbox and returns the mailbox name. 123 // The texture must have been previously consumed from a mailbox. 124 virtual std::string Produce(); 125 126 protected: 127 virtual ~Texture(); 128 gfx::Size size_; // in pixel 129 130 private: 131 friend class base::RefCounted<Texture>; 132 133 bool flipped_; 134 float device_scale_factor_; 135 136 DISALLOW_COPY_AND_ASSIGN(Texture); 137}; 138 139// This class represents a lock on the compositor, that can be used to prevent 140// commits to the compositor tree while we're waiting for an asynchronous 141// event. The typical use case is when waiting for a renderer to produce a frame 142// at the right size. The caller keeps a reference on this object, and drops the 143// reference once it desires to release the lock. 144// Note however that the lock is cancelled after a short timeout to ensure 145// responsiveness of the UI, so the compositor tree should be kept in a 146// "reasonable" state while the lock is held. 147// Don't instantiate this class directly, use Compositor::GetCompositorLock. 148class COMPOSITOR_EXPORT CompositorLock 149 : public base::RefCounted<CompositorLock>, 150 public base::SupportsWeakPtr<CompositorLock> { 151 private: 152 friend class base::RefCounted<CompositorLock>; 153 friend class Compositor; 154 155 explicit CompositorLock(Compositor* compositor); 156 ~CompositorLock(); 157 158 void CancelLock(); 159 160 Compositor* compositor_; 161 DISALLOW_COPY_AND_ASSIGN(CompositorLock); 162}; 163 164// This is only to be used for test. It allows execution of other tasks on 165// the current message loop before the current task finishs (there is a 166// potential for re-entrancy). 167class COMPOSITOR_EXPORT DrawWaiterForTest : public CompositorObserver { 168 public: 169 // Waits for a draw to be issued by the compositor. If the test times out 170 // here, there may be a logic error in the compositor code causing it 171 // not to draw. 172 static void Wait(Compositor* compositor); 173 174 // Waits for a commit instead of a draw. 175 static void WaitForCommit(Compositor* compositor); 176 177 private: 178 DrawWaiterForTest(); 179 virtual ~DrawWaiterForTest(); 180 181 void WaitImpl(Compositor* compositor); 182 183 // CompositorObserver implementation. 184 virtual void OnCompositingDidCommit(Compositor* compositor) OVERRIDE; 185 virtual void OnCompositingStarted(Compositor* compositor, 186 base::TimeTicks start_time) OVERRIDE; 187 virtual void OnCompositingEnded(Compositor* compositor) OVERRIDE; 188 virtual void OnCompositingAborted(Compositor* compositor) OVERRIDE; 189 virtual void OnCompositingLockStateChanged(Compositor* compositor) OVERRIDE; 190 virtual void OnUpdateVSyncParameters(Compositor* compositor, 191 base::TimeTicks timebase, 192 base::TimeDelta interval) OVERRIDE; 193 194 scoped_ptr<base::RunLoop> wait_run_loop_; 195 196 bool wait_for_commit_; 197 198 DISALLOW_COPY_AND_ASSIGN(DrawWaiterForTest); 199}; 200 201// Compositor object to take care of GPU painting. 202// A Browser compositor object is responsible for generating the final 203// displayable form of pixels comprising a single widget's contents. It draws an 204// appropriately transformed texture for each transformed view in the widget's 205// view hierarchy. 206class COMPOSITOR_EXPORT Compositor 207 : NON_EXPORTED_BASE(public cc::LayerTreeHostClient), 208 NON_EXPORTED_BASE(public cc::LayerTreeHostSingleThreadClient), 209 public base::SupportsWeakPtr<Compositor> { 210 public: 211 explicit Compositor(gfx::AcceleratedWidget widget); 212 virtual ~Compositor(); 213 214 static void Initialize(); 215 static bool WasInitializedWithThread(); 216 static scoped_refptr<base::MessageLoopProxy> GetCompositorMessageLoop(); 217 static void Terminate(); 218 219 // Schedules a redraw of the layer tree associated with this compositor. 220 void ScheduleDraw(); 221 222 // Sets the root of the layer tree drawn by this Compositor. The root layer 223 // must have no parent. The compositor's root layer is reset if the root layer 224 // is destroyed. NULL can be passed to reset the root layer, in which case the 225 // compositor will stop drawing anything. 226 // The Compositor does not own the root layer. 227 const Layer* root_layer() const { return root_layer_; } 228 Layer* root_layer() { return root_layer_; } 229 void SetRootLayer(Layer* root_layer); 230 231 // Called when we need the compositor to preserve the alpha channel in the 232 // output for situations when we want to render transparently atop something 233 // else, e.g. Aero glass. 234 void SetHostHasTransparentBackground(bool host_has_transparent_background); 235 236 // The scale factor of the device that this compositor is 237 // compositing layers on. 238 float device_scale_factor() const { return device_scale_factor_; } 239 240 // Draws the scene created by the layer tree and any visual effects. 241 void Draw(); 242 243 // Where possible, draws are scissored to a damage region calculated from 244 // changes to layer properties. This bypasses that and indicates that 245 // the whole frame needs to be drawn. 246 void ScheduleFullRedraw(); 247 248 // Schedule redraw and append damage_rect to the damage region calculated 249 // from changes to layer properties. 250 void ScheduleRedrawRect(const gfx::Rect& damage_rect); 251 252 void SetLatencyInfo(const LatencyInfo& latency_info); 253 254 // Reads the region |bounds_in_pixel| of the contents of the last rendered 255 // frame into the given bitmap. 256 // Returns false if the pixels could not be read. 257 bool ReadPixels(SkBitmap* bitmap, const gfx::Rect& bounds_in_pixel); 258 259 // Sets the compositor's device scale factor and size. 260 void SetScaleAndSize(float scale, const gfx::Size& size_in_pixel); 261 262 // Returns the size of the widget that is being drawn to in pixel coordinates. 263 const gfx::Size& size() const { return size_; } 264 265 // Sets the background color used for areas that aren't covered by 266 // the |root_layer|. 267 void SetBackgroundColor(SkColor color); 268 269 // Returns the widget for this compositor. 270 gfx::AcceleratedWidget widget() const { return widget_; } 271 272 // Compositor does not own observers. It is the responsibility of the 273 // observer to remove itself when it is done observing. 274 void AddObserver(CompositorObserver* observer); 275 void RemoveObserver(CompositorObserver* observer); 276 bool HasObserver(CompositorObserver* observer); 277 278 // Creates a compositor lock. Returns NULL if it is not possible to lock at 279 // this time (i.e. we're waiting to complete a previous unlock). 280 scoped_refptr<CompositorLock> GetCompositorLock(); 281 282 // Internal functions, called back by command-buffer contexts on swap buffer 283 // events. 284 285 // Signals swap has been posted. 286 void OnSwapBuffersPosted(); 287 288 // Signals swap has completed. 289 void OnSwapBuffersComplete(); 290 291 // Signals swap has aborted (e.g. lost context). 292 void OnSwapBuffersAborted(); 293 294 void OnUpdateVSyncParameters(base::TimeTicks timebase, 295 base::TimeDelta interval); 296 297 // LayerTreeHostClient implementation. 298 virtual void WillBeginMainFrame(int frame_id) OVERRIDE {} 299 virtual void DidBeginMainFrame() OVERRIDE {} 300 virtual void Animate(double frame_begin_time) OVERRIDE {} 301 virtual void Layout() OVERRIDE; 302 virtual void ApplyScrollAndScale(gfx::Vector2d scroll_delta, 303 float page_scale) OVERRIDE {} 304 virtual scoped_ptr<cc::OutputSurface> CreateOutputSurface(bool fallback) 305 OVERRIDE; 306 virtual void DidInitializeOutputSurface(bool success) OVERRIDE {} 307 virtual void WillCommit() OVERRIDE {} 308 virtual void DidCommit() OVERRIDE; 309 virtual void DidCommitAndDrawFrame() OVERRIDE; 310 virtual void DidCompleteSwapBuffers() OVERRIDE; 311 virtual scoped_refptr<cc::ContextProvider> 312 OffscreenContextProvider() OVERRIDE; 313 314 // cc::LayerTreeHostSingleThreadClient implementation. 315 virtual void ScheduleComposite() OVERRIDE; 316 virtual void ScheduleAnimation() OVERRIDE; 317 virtual void DidPostSwapBuffers() OVERRIDE; 318 virtual void DidAbortSwapBuffers() OVERRIDE; 319 320 int last_started_frame() { return last_started_frame_; } 321 int last_ended_frame() { return last_ended_frame_; } 322 323 bool IsLocked() { return compositor_lock_ != NULL; } 324 325 const cc::LayerTreeDebugState& GetLayerTreeDebugState() const; 326 void SetLayerTreeDebugState(const cc::LayerTreeDebugState& debug_state); 327 328 private: 329 friend class base::RefCounted<Compositor>; 330 friend class CompositorLock; 331 332 // Called by CompositorLock. 333 void UnlockCompositor(); 334 335 // Called to release any pending CompositorLock 336 void CancelCompositorLock(); 337 338 // Notifies the compositor that compositing is complete. 339 void NotifyEnd(); 340 341 gfx::Size size_; 342 343 // The root of the Layer tree drawn by this compositor. 344 Layer* root_layer_; 345 346 ObserverList<CompositorObserver> observer_list_; 347 348 gfx::AcceleratedWidget widget_; 349 scoped_refptr<cc::Layer> root_web_layer_; 350 scoped_ptr<cc::LayerTreeHost> host_; 351 352 // Used to verify that we have at most one draw swap in flight. 353 scoped_ptr<PostedSwapQueue> posted_swaps_; 354 355 // The device scale factor of the monitor that this compositor is compositing 356 // layers on. 357 float device_scale_factor_; 358 359 int last_started_frame_; 360 int last_ended_frame_; 361 362 bool next_draw_is_resize_; 363 364 bool disable_schedule_composite_; 365 366 CompositorLock* compositor_lock_; 367 368 // Prevent more than one draw from being scheduled. 369 bool defer_draw_scheduling_; 370 371 // Used to prevent Draw()s while a composite is in progress. 372 bool waiting_on_compositing_end_; 373 bool draw_on_compositing_end_; 374 375 base::WeakPtrFactory<Compositor> schedule_draw_factory_; 376 377 DISALLOW_COPY_AND_ASSIGN(Compositor); 378}; 379 380} // namespace ui 381 382#endif // UI_COMPOSITOR_COMPOSITOR_H_ 383