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 38 PageScaleConstraints::PageScaleConstraints() 39 : initialScale(-1), minimumScale(-1), maximumScale(-1) { } 40 41 PageScaleConstraints::PageScaleConstraints(float initial, float minimum, float maximum) 42 : initialScale(initial), minimumScale(minimum), maximumScale(maximum) { } 43 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 60 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 71 void PageScaleConstraints::clampAll() 72 { 73 if (minimumScale != -1 && maximumScale != -1) 74 maximumScale = std::max(minimumScale, maximumScale); 75 initialScale = clampToConstraints(initialScale); 76 } 77 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 95 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