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
36namespace blink {
37
38inline int blend(int from, int to, double progress)
39{
40    return lround(from + (to - from) * progress);
41}
42
43// For unsigned types.
44template <typename T>
45inline T blend(T from, T to, double progress)
46{
47    COMPILE_ASSERT(WTF::IsInteger<T>::value, BlendForUnsignedTypes);
48    return clampTo<T>(round(to > from ? from + (to - from) * progress : from - (from - to) * progress));
49}
50
51inline double blend(double from, double to, double progress)
52{
53    return from + (to - from) * progress;
54}
55
56inline float blend(float from, float to, double progress)
57{
58    return static_cast<float>(from + (to - from) * progress);
59}
60
61inline LayoutUnit blend(LayoutUnit from, LayoutUnit to, double progress)
62{
63    return from + (to - from) * progress;
64}
65
66inline 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
71inline 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.
77inline double accuracyForDuration(double duration)
78{
79    return 1.0 / (200.0 * duration);
80}
81
82} // namespace blink
83
84#endif // AnimationUtilities_h
85