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 #ifndef PageScaleConstraintsSet_h 32 #define PageScaleConstraintsSet_h 33 34 #include "PageScaleConstraints.h" 35 #include "core/dom/ViewportArguments.h" 36 #include "core/platform/graphics/IntSize.h" 37 38 namespace WebCore { 39 40 // This class harmonizes the viewport (particularly page scale) constraints from 41 // the meta viewport tag and other sources. 42 class PageScaleConstraintsSet { 43 public: 44 PageScaleConstraintsSet(); 45 46 PageScaleConstraints defaultConstraints() const; 47 48 // Settings defined in the website's viewport tag, if viewport tag support 49 // is enabled. 50 const PageScaleConstraints& pageDefinedConstraints() const { return m_pageDefinedConstraints; } 51 void updatePageDefinedConstraints(const ViewportArguments&, IntSize viewSize, int layoutFallbackWidth); 52 void adjustForAndroidWebViewQuirks(const ViewportArguments&, IntSize viewSize, int layoutFallbackWidth, float deviceScaleFactor, bool supportTargetDensityDPI, bool wideViewportQuirkEnabled, bool useWideViewport, bool loadWithOverviewMode); 53 54 // Constraints may also be set from Chromium -- this overrides any 55 // page-defined values. 56 const PageScaleConstraints& userAgentConstraints() const { return m_userAgentConstraints; } 57 void setUserAgentConstraints(const PageScaleConstraints&); 58 59 // Actual computed values, taking into account the above plus the current 60 // viewport size and document width. 61 const PageScaleConstraints& finalConstraints() const { return m_finalConstraints; } 62 void computeFinalConstraints(); 63 void adjustFinalConstraintsToContentsSize(IntSize viewSize, IntSize contentsSize, int nonOverlayScrollbarWidth); 64 65 void didChangeContentsSize(IntSize contentsSize, float pageScaleFactor); 66 67 // This should be set to true on each page load to note that the page scale 68 // factor needs to be reset to its initial value. 69 void setNeedsReset(bool); 70 bool needsReset() const { return m_needsReset; } 71 72 // This is set when one of the inputs to finalConstraints changes. 73 bool constraintsDirty() const { return m_constraintsDirty; } 74 75 private: 76 PageScaleConstraints computeConstraintsStack() const; 77 78 PageScaleConstraints m_pageDefinedConstraints; 79 PageScaleConstraints m_userAgentConstraints; 80 PageScaleConstraints m_finalConstraints; 81 82 int m_lastContentsWidth; 83 84 bool m_needsReset; 85 bool m_constraintsDirty; 86 }; 87 88 } // namespace WebCore 89 90 #endif // PageScaleConstraintsSet_h 91