gfx/webrender_bindings/RendererScreenshotGrabber.h

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #ifndef mozilla_layers_RendererScreenshotGrabber_h
   6 #define mozilla_layers_RendererScreenshotGrabber_h
   7
   8 #include "mozilla/TimeStamp.h"
   9 #include "mozilla/UniquePtr.h"
  10 #include "mozilla/gfx/Point.h"
  11 #include "mozilla/layers/ProfilerScreenshots.h"
  12 #include "mozilla/webrender/webrender_ffi.h"
  13 #include "nsTArray.h"
  14
  15 namespace mozilla {
  16 namespace wr {
  17
  18 struct Renderer;
  19 class RendererOGL;
  20
  21 /**
  22  * Used by |RendererOGL| to grab screenshots from WebRender and submit them to
  23  * the Gecko profiler.
  24  *
  25  * If the profiler is not running or the screenshots feature is disabled, no
  26  * work will be done.
  27  */
  28 class RendererScreenshotGrabber final {
  29  public:
  30   RendererScreenshotGrabber();
  31
  32   /**
  33    * Grab a screenshot from WebRender if we are profiling and screenshots are
  34    * enabled.
  35    *
  36    * The captured screenshot will not be mapped until the second call to
  37    * |MaybeProcessQueue| after this call to |MaybeGrabScreenshot|.
  38    */
  39   void MaybeGrabScreenshot(RendererOGL* aRendererOGL,
  40                            const gfx::IntSize& aWindowSize);
  41
  42   /**
  43    * Process the screenshots pending in the queue if we are profiling and
  44    * screenshots are enabled.
  45    */
  46   void MaybeProcessQueue(RendererOGL* aRenderer);
  47
  48  private:
  49   /**
  50    * Drop all our allocated memory when we are no longer profiling.
  51    *
  52    * This will also instruct WebRender to drop all its Gecko profiler
  53    * associated memory.
  54    */
  55   void Destroy(Renderer* aRenderer);
  56
  57   /**
  58    * Actually grab a screenshot from WebRender.
  59    */
  60   void GrabScreenshot(Renderer* aRenderer, const gfx::IntSize& aWindowSize);
  61
  62   /**
  63    * Process the screenshots pending in the queue.
  64    */
  65   void ProcessQueue(Renderer* aRenderer);
  66
  67   struct QueueItem {
  68     mozilla::TimeStamp mTimeStamp;
  69     AsyncScreenshotHandle mHandle;
  70     gfx::IntSize mScreenshotSize;
  71     gfx::IntSize mWindowSize;
  72   };
  73
  74   /**
  75    * The maximum size for screenshots, as dictated by
  76    * |ProfilerScrenshots::ScreenshotSize|.
  77    */
  78   gfx::IntSize mMaxScreenshotSize;
  79
  80   /**
  81    * The queue of screenshots waiting to be processed and submitted.
  82    */
  83   nsTArray<QueueItem> mQueue;
  84
  85   /**
  86    * The queue item for the current frame. This will be inserted into the queue
  87    * after a call to |MaybeProcessQueue| so it will be not be processed until
  88    * the next frame.
  89    */
  90   Maybe<QueueItem> mCurrentFrameQueueItem;
  91
  92   /**
  93    * Our handle to the profiler screenshots object.
  94    */
  95   RefPtr<mozilla::layers::ProfilerScreenshots> mProfilerScreenshots;
  96 };
  97
  98 }  // namespace wr
  99 }  // namespace mozilla
 100
 101 #endif  // mozilla_layers_RendererScreenshotGrabber_h