1/*
2 * Copyright (C) 2012 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 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include "web/FindInPageCoordinates.h"
33
34#include "core/dom/Node.h"
35#include "core/dom/Range.h"
36#include "core/frame/LocalFrame.h"
37#include "core/rendering/RenderBlock.h"
38#include "core/rendering/RenderBox.h"
39#include "core/rendering/RenderObject.h"
40#include "core/rendering/RenderPart.h"
41#include "core/rendering/RenderView.h"
42#include "core/rendering/style/RenderStyle.h"
43#include "platform/geometry/FloatPoint.h"
44#include "platform/geometry/FloatQuad.h"
45#include "platform/geometry/IntPoint.h"
46
47namespace blink {
48
49static const RenderBlock* enclosingScrollableAncestor(const RenderObject* renderer)
50{
51    ASSERT(!renderer->isRenderView());
52
53    // Trace up the containingBlocks until we reach either the render view or a scrollable object.
54    const RenderBlock* container = renderer->containingBlock();
55    while (!container->hasOverflowClip() && !container->isRenderView())
56        container = container->containingBlock();
57    return container;
58}
59
60static FloatRect toNormalizedRect(const FloatRect& absoluteRect, const RenderObject* renderer, const RenderBlock* container)
61{
62    ASSERT(renderer);
63
64    ASSERT(container || renderer->isRenderView());
65    if (!container)
66        return FloatRect();
67
68    // We want to normalize by the max layout overflow size instead of only the visible bounding box.
69    // Quads and their enclosing bounding boxes need to be used in order to keep results transform-friendly.
70    FloatPoint scrolledOrigin;
71
72    // For overflow:scroll we need to get where the actual origin is independently of the scroll.
73    if (container->hasOverflowClip())
74        scrolledOrigin = -IntPoint(container->scrolledContentOffset());
75
76    FloatRect overflowRect(scrolledOrigin, container->maxLayoutOverflow());
77    FloatRect containerRect = container->localToAbsoluteQuad(FloatQuad(overflowRect)).enclosingBoundingBox();
78
79    if (containerRect.isEmpty())
80        return FloatRect();
81
82    // Make the coordinates relative to the container enclosing bounding box.
83    // Since we work with rects enclosing quad unions this is still transform-friendly.
84    FloatRect normalizedRect = absoluteRect;
85    normalizedRect.moveBy(-containerRect.location());
86
87    // Fixed positions do not make sense in this coordinate system, but need to leave consistent tickmarks.
88    // So, use their position when the view is not scrolled, like an absolute position.
89    if (renderer->style()->position() == FixedPosition && container->isRenderView())
90        normalizedRect.move(-toRenderView(container)->frameView()->scrollOffsetForFixedPosition());
91
92    normalizedRect.scale(1 / containerRect.width(), 1 / containerRect.height());
93    return normalizedRect;
94}
95
96FloatRect findInPageRectFromAbsoluteRect(const FloatRect& inputRect, const RenderObject* baseRenderer)
97{
98    if (!baseRenderer || inputRect.isEmpty())
99        return FloatRect();
100
101    // Normalize the input rect to its container block.
102    const RenderBlock* baseContainer = enclosingScrollableAncestor(baseRenderer);
103    FloatRect normalizedRect = toNormalizedRect(inputRect, baseRenderer, baseContainer);
104
105    // Go up across frames.
106    for (const RenderBox* renderer = baseContainer; renderer; ) {
107
108        // Go up the render tree until we reach the root of the current frame (the RenderView).
109        while (!renderer->isRenderView()) {
110            const RenderBlock* container = enclosingScrollableAncestor(renderer);
111
112            // Compose the normalized rects.
113            FloatRect normalizedBoxRect = toNormalizedRect(renderer->absoluteBoundingBoxRect(), renderer, container);
114            normalizedRect.scale(normalizedBoxRect.width(), normalizedBoxRect.height());
115            normalizedRect.moveBy(normalizedBoxRect.location());
116
117            renderer = container;
118        }
119
120        ASSERT(renderer->isRenderView());
121
122        // Jump to the renderer owning the frame, if any.
123        renderer = renderer->frame() ? renderer->frame()->ownerRenderer() : 0;
124    }
125
126    return normalizedRect;
127}
128
129FloatRect findInPageRectFromRange(Range* range)
130{
131    if (!range || !range->firstNode())
132        return FloatRect();
133
134    return findInPageRectFromAbsoluteRect(RenderObject::absoluteBoundingBoxRectForRange(range), range->firstNode()->renderer());
135}
136
137} // namespace blink
138