third_party/WebKit/Source/platform/geometry/TransformState.h

   1 /*
   2  * Copyright (C) 2011 Apple 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
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef TransformState_h
  27 #define TransformState_h
  28
  29 #include "platform/geometry/FloatPoint.h"
  30 #include "platform/geometry/FloatQuad.h"
  31 #include "platform/geometry/IntSize.h"
  32 #include "platform/geometry/LayoutSize.h"
  33 #include "platform/transforms/AffineTransform.h"
  34 #include "platform/transforms/TransformationMatrix.h"
  35 #include "wtf/OwnPtr.h"
  36
  37 namespace blink {
  38
  39 class PLATFORM_EXPORT TransformState {
  40 public:
  41     enum TransformDirection { ApplyTransformDirection, UnapplyInverseTransformDirection };
  42     enum TransformAccumulation { FlattenTransform, AccumulateTransform };
  43
  44     TransformState(TransformDirection mappingDirection, const FloatPoint& p, const FloatQuad& quad)
  45         : m_lastPlanarPoint(p)
  46         , m_lastPlanarQuad(quad)
  47         , m_accumulatingTransform(false)
  48         , m_mapPoint(true)
  49         , m_mapQuad(true)
  50         , m_direction(mappingDirection)
  51     {
  52     }
  53
  54     TransformState(TransformDirection mappingDirection, const FloatPoint& p)
  55         : m_lastPlanarPoint(p)
  56         , m_accumulatingTransform(false)
  57         , m_mapPoint(true)
  58         , m_mapQuad(false)
  59         , m_direction(mappingDirection)
  60     {
  61     }
  62
  63     TransformState(TransformDirection mappingDirection, const FloatQuad& quad)
  64         : m_lastPlanarQuad(quad)
  65         , m_accumulatingTransform(false)
  66         , m_mapPoint(false)
  67         , m_mapQuad(true)
  68         , m_direction(mappingDirection)
  69     {
  70     }
  71
  72     TransformState(const TransformState& other) { *this = other; }
  73
  74     TransformState& operator=(const TransformState&);
  75
  76     void setQuad(const FloatQuad& quad)
  77     {
  78         // FIXME: this assumes that the quad being added is in the coordinate system of the current state.
  79         // This breaks if we're simultaneously mapping a point. https://bugs.webkit.org/show_bug.cgi?id=106680
  80         ASSERT(!m_mapPoint);
  81         m_accumulatedOffset = LayoutSize();
  82         m_lastPlanarQuad = quad;
  83     }
  84
  85     void move(LayoutUnit x, LayoutUnit y, TransformAccumulation accumulate = FlattenTransform)
  86     {
  87         move(LayoutSize(x, y), accumulate);
  88     }
  89
  90     void move(const LayoutSize&, TransformAccumulation = FlattenTransform);
  91     void move(const IntSize& size, TransformAccumulation accumulate = FlattenTransform)
  92     {
  93         move(LayoutSize(size), accumulate);
  94     }
  95     void applyTransform(const AffineTransform& transformFromContainer, TransformAccumulation = FlattenTransform, bool* wasClamped = 0);
  96     void applyTransform(const TransformationMatrix& transformFromContainer, TransformAccumulation = FlattenTransform, bool* wasClamped = 0);
  97     void flatten(bool* wasClamped = 0);
  98
  99     // Return the coords of the point or quad in the last flattened layer
 100     FloatPoint lastPlanarPoint() const { return m_lastPlanarPoint; }
 101     FloatQuad lastPlanarQuad() const { return m_lastPlanarQuad; }
 102
 103     // Return the point or quad mapped through the current transform
 104     FloatPoint mappedPoint(bool* wasClamped = 0) const;
 105     FloatQuad mappedQuad(bool* wasClamped = 0) const;
 106
 107 private:
 108     void translateTransform(const LayoutSize&);
 109     void translateMappedCoordinates(const LayoutSize&);
 110     void flattenWithTransform(const TransformationMatrix&, bool* wasClamped);
 111     void applyAccumulatedOffset();
 112
 113     FloatPoint m_lastPlanarPoint;
 114     FloatQuad m_lastPlanarQuad;
 115
 116     // We only allocate the transform if we need to
 117     OwnPtr<TransformationMatrix> m_accumulatedTransform;
 118     LayoutSize m_accumulatedOffset;
 119     bool m_accumulatingTransform;
 120     bool m_mapPoint, m_mapQuad;
 121     TransformDirection m_direction;
 122 };
 123
 124 } // namespace blink
 125
 126 #endif // TransformState_h