content/browser/renderer_host/compositing_iosurface_layer_mac.h

   1 // Copyright 2013 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 CONTENT_BROWSER_RENDERER_HOST_COMPOSITING_IOSURFACE_LAYER_MAC_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_COMPOSITING_IOSURFACE_LAYER_MAC_H_
   7
   8 #import <Cocoa/Cocoa.h>
   9
  10 #include "base/mac/scoped_cftyperef.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/timer/timer.h"
  13
  14 @class CompositingIOSurfaceLayer;
  15
  16 namespace content {
  17 class CompositingIOSurfaceMac;
  18 class CompositingIOSurfaceContext;
  19
  20 // The interface through which the CompositingIOSurfaceLayer calls back into
  21 // the structrue that created it (RenderWidgetHostViewMac or
  22 // BrowserCompositorViewMac).
  23 class CompositingIOSurfaceLayerClient {
  24  public:
  25   // Used to indicate that the layer should attempt to draw immediately and
  26   // should (even if the draw is elided by the system), ack the frame
  27   // immediately.
  28   virtual bool AcceleratedLayerShouldAckImmediately() const = 0;
  29
  30   // Called when a frame is drawn or when, because the layer is not visible, it
  31   // is known that the frame will never drawn.
  32   virtual void AcceleratedLayerDidDrawFrame() = 0;
  33
  34   // Called when an error prevents the frame from being drawn.
  35   virtual void AcceleratedLayerHitError() = 0;
  36 };
  37
  38 // CompositingIOSurfaceLayerHelper provides C++ functionality needed for the
  39 // CompositingIOSurfaceLayer class, and does most of the heavy lifting for the
  40 // class.
  41 // TODO(ccameron): This class should own CompositingIOSurfaceLayer, rather than
  42 // vice versa.
  43 class CompositingIOSurfaceLayerHelper {
  44  public:
  45   CompositingIOSurfaceLayerHelper(CompositingIOSurfaceLayerClient* client,
  46                                   CompositingIOSurfaceLayer* layer);
  47   ~CompositingIOSurfaceLayerHelper();
  48
  49   // Called when the CompositingIOSurfaceLayer gets a new frame.
  50   void GotNewFrame();
  51
  52   // Called whenever -[CompositingIOSurfaceLayer setNeedsDisplay] is called.
  53   void SetNeedsDisplay();
  54
  55   // Called whenever -[CompositingIOSurfaceLayer canDrawInCGLContext] is called,
  56   // to determine if a new frame should be drawn.
  57   bool CanDraw();
  58
  59   // Called whenever -[CompositingIOSurfaceLayer drawInCGLContext] draws a
  60   // frame.
  61   void DidDraw(bool success);
  62
  63   // Immediately re-draw the layer, even if the content has not changed, and
  64   // ensure that the frame be acked.
  65   void SetNeedsDisplayAndDisplayAndAck();
  66
  67   // Immediately draw the layer, only if one is pending, and ensure that the
  68   // frame be acked.
  69   void DisplayIfNeededAndAck();
  70
  71   // Mark a bracket in which new frames are being pumped in a restricted nested
  72   // run loop. During this time frames are acked immediately and draws are
  73   // deferred until the bracket ends.
  74   void BeginPumpingFrames();
  75   void EndPumpingFrames();
  76
  77  private:
  78   // Called whenever the frame provided in GotNewFrame should be acknowledged
  79   // (this may be because it was drawn, or it may be to unblock the
  80   // compositor).
  81   void AckPendingFrame(bool success);
  82
  83   void TimerFired();
  84
  85   // The client that the owning layer was created with.
  86   content::CompositingIOSurfaceLayerClient* const client_;
  87
  88   // The layer that owns this helper.
  89   CompositingIOSurfaceLayer* const layer_;
  90
  91   // Used to track when canDrawInCGLContext should return YES. This can be
  92   // in response to receiving a new compositor frame, or from any of the events
  93   // that cause setNeedsDisplay to be called on the layer.
  94   bool needs_display_;
  95
  96   // This is set when a frame is received, and un-set when the frame is drawn.
  97   bool has_pending_frame_;
  98
  99   // Incremented every time that this layer is asked to draw but does not have
 100   // new content to draw.
 101   uint64 did_not_draw_counter_;
 102
 103   // Set when inside a BeginPumpingFrames/EndPumpingFrames block.
 104   bool is_pumping_frames_;
 105
 106   // The browser places back-pressure on the GPU by not acknowledging swap
 107   // calls until they appear on the screen. This can lead to hangs if the
 108   // view is moved offscreen (among other things). Prevent hangs by always
 109   // acknowledging the frame after timeout of 1/6th of a second  has passed.
 110   base::DelayTimer<CompositingIOSurfaceLayerHelper> timer_;
 111 };
 112
 113 }  // namespace content
 114
 115 // The CoreAnimation layer for drawing accelerated content.
 116 @interface CompositingIOSurfaceLayer : CAOpenGLLayer {
 117  @private
 118   scoped_refptr<content::CompositingIOSurfaceMac> iosurface_;
 119   scoped_refptr<content::CompositingIOSurfaceContext> context_;
 120
 121   scoped_ptr<content::CompositingIOSurfaceLayerHelper> helper_;
 122 }
 123
 124 - (content::CompositingIOSurfaceMac*)iosurface;
 125 - (content::CompositingIOSurfaceContext*)context;
 126
 127 - (id)initWithIOSurface:(scoped_refptr<content::CompositingIOSurfaceMac>)
 128                             iosurface
 129         withScaleFactor:(float)scale_factor
 130              withClient:(content::CompositingIOSurfaceLayerClient*)client;
 131
 132 // Mark that the client is no longer valid and cannot be called back into. This
 133 // must be called before the layer is destroyed.
 134 - (void)resetClient;
 135
 136 // Called when a new frame is received.
 137 - (void)gotNewFrame;
 138
 139 // Force a draw immediately (even if this means re-displaying a previously
 140 // displayed frame).
 141 - (void)setNeedsDisplayAndDisplayAndAck;
 142
 143 // Force a draw immediately, but only if one was requested.
 144 - (void)displayIfNeededAndAck;
 145
 146 // Mark a bracket in which new frames are being pumped in a restricted nested
 147 // run loop.
 148 - (void)beginPumpingFrames;
 149 - (void)endPumpingFrames;
 150 @end
 151
 152 #endif  // CONTENT_BROWSER_RENDERER_HOST_COMPOSITING_IOSURFACE_LAYER_MAC_H_