1 /*
2 * Copyright (C) 2013 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 "core/page/PageScaleConstraints.h"
33
34 #include <algorithm>
35
36 namespace WebCore {
37
PageScaleConstraints()38 PageScaleConstraints::PageScaleConstraints()
39 : initialScale(-1), minimumScale(-1), maximumScale(-1) { }
40
PageScaleConstraints(float initial,float minimum,float maximum)41 PageScaleConstraints::PageScaleConstraints(float initial, float minimum, float maximum)
42 : initialScale(initial), minimumScale(minimum), maximumScale(maximum) { }
43
overrideWith(const PageScaleConstraints & other)44 void PageScaleConstraints::overrideWith(const PageScaleConstraints& other)
45 {
46 if (other.initialScale != -1) {
47 initialScale = other.initialScale;
48 if (minimumScale != -1)
49 minimumScale = std::min(minimumScale, other.initialScale);
50 }
51 if (other.minimumScale != -1)
52 minimumScale = other.minimumScale;
53 if (other.maximumScale != -1)
54 maximumScale = other.maximumScale;
55 if (!other.layoutSize.isEmpty())
56 layoutSize = other.layoutSize;
57 clampAll();
58 }
59
clampToConstraints(float pageScaleFactor) const60 float PageScaleConstraints::clampToConstraints(float pageScaleFactor) const
61 {
62 if (pageScaleFactor == -1)
63 return pageScaleFactor;
64 if (minimumScale != -1)
65 pageScaleFactor = std::max(pageScaleFactor, minimumScale);
66 if (maximumScale != -1)
67 pageScaleFactor = std::min(pageScaleFactor, maximumScale);
68 return pageScaleFactor;
69 }
70
clampAll()71 void PageScaleConstraints::clampAll()
72 {
73 if (minimumScale != -1 && maximumScale != -1)
74 maximumScale = std::max(minimumScale, maximumScale);
75 initialScale = clampToConstraints(initialScale);
76 }
77
fitToContentsWidth(float contentsWidth,int viewWidthNotIncludingScrollbars)78 void PageScaleConstraints::fitToContentsWidth(float contentsWidth, int viewWidthNotIncludingScrollbars)
79 {
80 if (!contentsWidth || !viewWidthNotIncludingScrollbars)
81 return;
82
83 // Clamp the minimum scale so that the viewport can't exceed the document
84 // width.
85 minimumScale = std::max(minimumScale, viewWidthNotIncludingScrollbars / contentsWidth);
86
87 // If the initial scale wasn't defined, set it to minimum scale now that we
88 // know the real value.
89 if (initialScale == -1)
90 initialScale = minimumScale;
91
92 clampAll();
93 }
94
operator ==(const PageScaleConstraints & other) const95 bool PageScaleConstraints::operator==(const PageScaleConstraints& other) const
96 {
97 return layoutSize == other.layoutSize
98 && initialScale == other.initialScale
99 && minimumScale == other.minimumScale
100 && maximumScale == other.maximumScale;
101 }
102
103 } // namespace WebCore
104