1/*
2 * Copyright (C) 2011 Apple 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 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef DrawingAreaImpl_h
27#define DrawingAreaImpl_h
28
29#include "DrawingArea.h"
30#include "LayerTreeHost.h"
31#include <WebCore/Region.h>
32#include <wtf/RunLoop.h>
33
34namespace WebCore {
35    class GraphicsContext;
36}
37
38namespace WebKit {
39
40class ShareableBitmap;
41class UpdateInfo;
42
43class DrawingAreaImpl : public DrawingArea {
44public:
45    DrawingAreaImpl(WebPage&, const WebPageCreationParameters&);
46    virtual ~DrawingAreaImpl();
47
48    void layerHostDidFlushLayers();
49
50private:
51    // DrawingArea
52    virtual void setNeedsDisplay() override;
53    virtual void setNeedsDisplayInRect(const WebCore::IntRect&) override;
54    virtual void scroll(const WebCore::IntRect& scrollRect, const WebCore::IntSize& scrollDelta);
55    virtual void pageBackgroundTransparencyChanged() override;
56    virtual void setLayerTreeStateIsFrozen(bool);
57    virtual bool layerTreeStateIsFrozen() const { return m_layerTreeStateIsFrozen; }
58    virtual LayerTreeHost* layerTreeHost() const { return m_layerTreeHost.get(); }
59    virtual void forceRepaint();
60    virtual bool forceRepaintAsync(uint64_t callbackID);
61
62    virtual void didInstallPageOverlay(PageOverlay*);
63    virtual void didUninstallPageOverlay(PageOverlay*);
64    virtual void setPageOverlayNeedsDisplay(PageOverlay*, const WebCore::IntRect&);
65    virtual void setPageOverlayOpacity(PageOverlay*, float);
66
67    virtual void setPaintingEnabled(bool);
68    virtual void updatePreferences(const WebPreferencesStore&) override;
69
70    virtual WebCore::GraphicsLayerFactory* graphicsLayerFactory() override;
71    virtual void setRootCompositingLayer(WebCore::GraphicsLayer*) override;
72    virtual void scheduleCompositingLayerFlush() override;
73    virtual void scheduleCompositingLayerFlushImmediately() override;
74
75    // IPC message handlers.
76    virtual void updateBackingStoreState(uint64_t backingStoreStateID, bool respondImmediately, float deviceScaleFactor, const WebCore::IntSize&, const WebCore::IntSize& scrollOffset);
77    virtual void didUpdate();
78    virtual void suspendPainting();
79    virtual void resumePainting();
80
81    void sendDidUpdateBackingStoreState();
82
83    void enterAcceleratedCompositingMode(WebCore::GraphicsLayer*);
84    void exitAcceleratedCompositingModeSoon();
85    bool exitAcceleratedCompositingModePending() const { return m_exitCompositingTimer.isActive(); }
86    void exitAcceleratedCompositingMode();
87
88    void scheduleDisplay();
89    void displayTimerFired();
90    void display();
91    void display(UpdateInfo&);
92
93    uint64_t m_backingStoreStateID;
94
95    WebCore::Region m_dirtyRegion;
96    WebCore::IntRect m_scrollRect;
97    WebCore::IntSize m_scrollOffset;
98
99    // Whether painting is enabled. If painting is disabled, any calls to setNeedsDisplay and scroll are ignored.
100    bool m_isPaintingEnabled;
101
102    // Whether we're currently processing an UpdateBackingStoreState message.
103    bool m_inUpdateBackingStoreState;
104
105    // When true, we should send an UpdateBackingStoreState message instead of any other messages
106    // we normally send to the UI process.
107    bool m_shouldSendDidUpdateBackingStoreState;
108
109    // Whether we're waiting for a DidUpdate message. Used for throttling paints so that the
110    // web process won't paint more frequent than the UI process can handle.
111    bool m_isWaitingForDidUpdate;
112
113    // True between sending the 'enter compositing' messages, and the 'exit compositing' message.
114    bool m_compositingAccordingToProxyMessages;
115
116    // When true, we maintain the layer tree in its current state by not leaving accelerated compositing mode
117    // and not scheduling layer flushes.
118    bool m_layerTreeStateIsFrozen;
119
120    // True when we were asked to exit accelerated compositing mode but couldn't because layer tree
121    // state was frozen.
122    bool m_wantsToExitAcceleratedCompositingMode;
123
124    // Whether painting is suspended. We'll still keep track of the dirty region but we
125    // won't paint until painting has resumed again.
126    bool m_isPaintingSuspended;
127    bool m_alwaysUseCompositing;
128
129    RunLoop::Timer<DrawingAreaImpl> m_displayTimer;
130    RunLoop::Timer<DrawingAreaImpl> m_exitCompositingTimer;
131
132    // The layer tree host that handles accelerated compositing.
133    RefPtr<LayerTreeHost> m_layerTreeHost;
134};
135
136} // namespace WebKit
137
138#endif // DrawingAreaImpl_h
139