1/*
2 * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
3 * Copyright (C) 2008 Google Inc.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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 COMPUTER, INC. ``AS IS'' AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include "config.h"
28
29#include "Document.h"
30#include "FloatRect.h"
31#include "GraphicsContext.h"
32#include "ImageBuffer.h"
33#include "RenderView.h"
34#include "Settings.h"
35
36namespace WebCore {
37
38namespace {
39
40struct ScopedState {
41    ScopedState(Frame* theFrame, RenderObject* theRenderer)
42        : frame(theFrame)
43        , renderer(theRenderer)
44        , paintBehavior(frame->view()->paintBehavior())
45        , backgroundColor(frame->view()->baseBackgroundColor())
46    {
47    }
48
49    ~ScopedState()
50    {
51        if (renderer)
52            renderer->updateDragState(false);
53        frame->view()->setPaintBehavior(paintBehavior);
54        frame->view()->setBaseBackgroundColor(backgroundColor);
55        frame->view()->setNodeToDraw(0);
56    }
57
58    Frame* frame;
59    RenderObject* renderer;
60    PaintBehavior paintBehavior;
61    Color backgroundColor;
62};
63
64} // namespace
65
66DragImageRef Frame::nodeImage(Node* node)
67{
68    RenderObject* renderer = node->renderer();
69    if (!renderer)
70        return 0;
71
72    const ScopedState state(this, renderer);
73
74    renderer->updateDragState(true);
75    m_view->setPaintBehavior(state.paintBehavior | PaintBehaviorFlattenCompositingLayers);
76    // When generating the drag image for an element, ignore the document background.
77    m_view->setBaseBackgroundColor(colorWithOverrideAlpha(Color::white, 1.0));
78    m_doc->updateLayout();
79    m_view->setNodeToDraw(node); // Enable special sub-tree drawing mode.
80
81    IntRect topLevelRect;
82    IntRect paintingRect = renderer->paintingRootRect(topLevelRect);
83
84    OwnPtr<ImageBuffer> buffer(ImageBuffer::create(paintingRect.size()));
85    if (!buffer)
86        return 0;
87    buffer->context()->translate(-paintingRect.x(), -paintingRect.y());
88    buffer->context()->clip(FloatRect(0, 0, paintingRect.maxX(), paintingRect.maxY()));
89
90    m_view->paintContents(buffer->context(), paintingRect);
91
92    RefPtr<Image> image = buffer->copyImage();
93    return createDragImageFromImage(image.get());
94}
95
96DragImageRef Frame::dragImageForSelection()
97{
98    if (!selection()->isRange())
99        return 0;
100
101    const ScopedState state(this, 0);
102    m_view->setPaintBehavior(PaintBehaviorSelectionOnly);
103    m_doc->updateLayout();
104
105    IntRect paintingRect = enclosingIntRect(selection()->bounds());
106
107    OwnPtr<ImageBuffer> buffer(ImageBuffer::create(paintingRect.size()));
108    if (!buffer)
109        return 0;
110    buffer->context()->translate(-paintingRect.x(), -paintingRect.y());
111    buffer->context()->clip(FloatRect(0, 0, paintingRect.maxX(), paintingRect.maxY()));
112
113    m_view->paintContents(buffer->context(), paintingRect);
114
115    RefPtr<Image> image = buffer->copyImage();
116    return createDragImageFromImage(image.get());
117}
118
119} // namespace WebCore
120