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 are
6 * met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above
12 * copyright notice, this list of conditions and the following disclaimer
13 * in the documentation and/or other materials provided with the
14 * distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY GOOGLE INC. AND ITS CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GOOGLE INC.
20 * OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include "config.h"
30#include "web/PageOverlay.h"
31
32#include "core/frame/Settings.h"
33#include "core/page/Page.h"
34#include "platform/graphics/GraphicsContext.h"
35#include "platform/graphics/GraphicsLayer.h"
36#include "platform/graphics/GraphicsLayerClient.h"
37#include "public/platform/WebLayer.h"
38#include "public/web/WebPageOverlay.h"
39#include "public/web/WebViewClient.h"
40#include "web/WebViewImpl.h"
41
42namespace blink {
43
44namespace {
45
46WebCanvas* ToWebCanvas(GraphicsContext* gc)
47{
48    return gc->canvas();
49}
50
51} // namespace
52
53PassOwnPtr<PageOverlay> PageOverlay::create(WebViewImpl* viewImpl, WebPageOverlay* overlay)
54{
55    return adoptPtr(new PageOverlay(viewImpl, overlay));
56}
57
58PageOverlay::PageOverlay(WebViewImpl* viewImpl, WebPageOverlay* overlay)
59    : m_viewImpl(viewImpl)
60    , m_overlay(overlay)
61    , m_zOrder(0)
62{
63}
64
65class OverlayGraphicsLayerClientImpl : public GraphicsLayerClient {
66public:
67    static PassOwnPtr<OverlayGraphicsLayerClientImpl> create(WebPageOverlay* overlay)
68    {
69        return adoptPtr(new OverlayGraphicsLayerClientImpl(overlay));
70    }
71
72    virtual ~OverlayGraphicsLayerClientImpl() { }
73
74    virtual void notifyAnimationStarted(const GraphicsLayer*, double monotonicTime) OVERRIDE { }
75
76    virtual void paintContents(const GraphicsLayer*, GraphicsContext& gc, GraphicsLayerPaintingPhase, const IntRect& inClip)
77    {
78        gc.save();
79        m_overlay->paintPageOverlay(ToWebCanvas(&gc));
80        gc.restore();
81    }
82
83    virtual String debugName(const GraphicsLayer* graphicsLayer) OVERRIDE
84    {
85        return String("WebViewImpl Page Overlay Content Layer");
86    }
87
88private:
89    explicit OverlayGraphicsLayerClientImpl(WebPageOverlay* overlay)
90        : m_overlay(overlay)
91    {
92    }
93
94    WebPageOverlay* m_overlay;
95};
96
97void PageOverlay::clear()
98{
99    invalidateWebFrame();
100
101    if (m_layer) {
102        m_layer->removeFromParent();
103        if (Page* page = m_viewImpl->page())
104            page->inspectorController().didRemovePageOverlay(m_layer.get());
105        m_layer = nullptr;
106        m_layerClient = nullptr;
107    }
108}
109
110void PageOverlay::update()
111{
112    invalidateWebFrame();
113
114    if (!m_layer) {
115        m_layerClient = OverlayGraphicsLayerClientImpl::create(m_overlay);
116        m_layer = GraphicsLayer::create(m_viewImpl->graphicsLayerFactory(), m_layerClient.get());
117        m_layer->setDrawsContent(true);
118
119        if (Page* page = m_viewImpl->page())
120            page->inspectorController().willAddPageOverlay(m_layer.get());
121
122        // This is required for contents of overlay to stay in sync with the page while scrolling.
123        WebLayer* platformLayer = m_layer->platformLayer();
124        platformLayer->setShouldScrollOnMainThread(true);
125    }
126
127    FloatSize size(m_viewImpl->size());
128    if (size != m_layer->size()) {
129        // Triggers re-adding to root layer to ensure that we are on top of
130        // scrollbars.
131        m_layer->removeFromParent();
132        m_layer->setSize(size);
133    }
134
135    m_viewImpl->setOverlayLayer(m_layer.get());
136    m_layer->setNeedsDisplay();
137}
138
139void PageOverlay::paintWebFrame(GraphicsContext& gc)
140{
141    if (!m_viewImpl->isAcceleratedCompositingActive()) {
142        gc.save();
143        m_overlay->paintPageOverlay(ToWebCanvas(&gc));
144        gc.restore();
145    }
146}
147
148void PageOverlay::invalidateWebFrame()
149{
150    // WebPageOverlay does the actual painting of the overlay.
151    // Here we just make sure to invalidate.
152    if (!m_viewImpl->isAcceleratedCompositingActive()) {
153        // FIXME: able to invalidate a smaller rect.
154        // FIXME: Is it important to just invalidate a smaller rect given that
155        // this is not on a critical codepath? In order to do so, we'd
156        // have to take scrolling into account.
157        const WebSize& size = m_viewImpl->size();
158        WebRect damagedRect(0, 0, size.width, size.height);
159        if (m_viewImpl->client())
160            m_viewImpl->client()->didInvalidateRect(damagedRect);
161    }
162}
163
164} // namespace blink
165