third_party/WebKit/Source/platform/animation/AnimationUtilities.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 AnimationUtilities_h
  27 #define AnimationUtilities_h
  28
  29 #include "platform/LayoutUnit.h"
  30 #include "platform/PlatformExport.h"
  31 #include "platform/geometry/FloatPoint.h"
  32 #include "platform/geometry/IntPoint.h"
  33 #include "wtf/MathExtras.h"
  34 #include "wtf/TypeTraits.h"
  35
  36 namespace blink {
  37
  38 inline int blend(int from, int to, double progress)
  39 {
  40     return lround(from + (to - from) * progress);
  41 }
  42
  43 // For unsigned types.
  44 template <typename T>
  45 inline T blend(T from, T to, double progress)
  46 {
  47     static_assert(WTF::IsInteger<T>::value, "blend can only be used with integer types");
  48     return clampTo<T>(round(to > from ? from + (to - from) * progress : from - (from - to) * progress));
  49 }
  50
  51 inline double blend(double from, double to, double progress)
  52 {
  53     return from + (to - from) * progress;
  54 }
  55
  56 inline float blend(float from, float to, double progress)
  57 {
  58     return static_cast<float>(from + (to - from) * progress);
  59 }
  60
  61 inline LayoutUnit blend(LayoutUnit from, LayoutUnit to, double progress)
  62 {
  63     return from + (to - from) * progress;
  64 }
  65
  66 inline IntPoint blend(const IntPoint& from, const IntPoint& to, double progress)
  67 {
  68     return IntPoint(blend(from.x(), to.x(), progress), blend(from.y(), to.y(), progress));
  69 }
  70
  71 inline FloatPoint blend(const FloatPoint& from, const FloatPoint& to, double progress)
  72 {
  73     return FloatPoint(blend(from.x(), to.x(), progress), blend(from.y(), to.y(), progress));
  74 }
  75
  76 // Calculates the accuracy for evaluating a timing function for an animation with the specified duration.
  77 inline double accuracyForDuration(double duration)
  78 {
  79     return 1.0 / (200.0 * duration);
  80 }
  81
  82 } // namespace blink
  83
  84 #endif // AnimationUtilities_h