third_party/WebKit/public/platform/WebContentLayerClient.h

   1 /*
   2  * Copyright (C) 2011 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  17  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  20  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  21  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef WebContentLayerClient_h
  27 #define WebContentLayerClient_h
  28
  29 #include "WebCanvas.h"
  30 #include "WebCommon.h"
  31
  32 namespace blink {
  33
  34 class WebDisplayItemList;
  35 struct WebRect;
  36
  37 class BLINK_PLATFORM_EXPORT WebContentLayerClient {
  38 public:
  39     enum PaintingControlSetting {
  40         PaintDefaultBehavior,
  41         DisplayListConstructionDisabled,
  42         DisplayListCachingDisabled,
  43         DisplayListPaintingDisabled
  44     };
  45
  46     // Paints the content area for the layer, typically dirty rects submitted
  47     // through WebContentLayer::setNeedsDisplay, submitting drawing commands
  48     // through the WebCanvas.
  49     // The canvas is already clipped to the |clip| rect.
  50     // The |PaintingControlSetting| enum controls painting to isolate different components in performance tests.
  51     virtual void paintContents(WebCanvas*, const WebRect& clip, PaintingControlSetting = PaintDefaultBehavior) = 0;
  52
  53     // Paints the content area for the layer, typically dirty rects submitted
  54     // through WebContentLayer::setNeedsDisplayInRect, submitting drawing commands
  55     // to populate the WebDisplayItemList.
  56     // The |clip| rect defines the region of interest. The resulting WebDisplayItemList should contain
  57     // sufficient content to correctly paint the rect, but may also contain other content. The result
  58     // will be clipped on playback.
  59     // The |PaintingControlSetting| enum controls painting to isolate different components in performance tests.
  60     // Currently the DisplayListConstructionDisabled does nothing.
  61     virtual void paintContents(
  62         WebDisplayItemList*,
  63         const WebRect& clip,
  64         PaintingControlSetting = PaintDefaultBehavior) = 0;
  65
  66     // Returns an estimate of the current memory usage within this object,
  67     // excluding memory shared with painting artifacts (i.e.,
  68     // WebDisplayItemList). Should be invoked after paintContents, so that the
  69     // result includes data cached internally during painting.
  70     virtual size_t approximateUnsharedMemoryUsage() const { return 0; }
  71
  72 protected:
  73     virtual ~WebContentLayerClient() { }
  74 };
  75
  76 } // namespace blink
  77
  78 #endif // WebContentLayerClient_h