animationbase.cpp

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/*
 * Copyright (C) 2007 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer. 
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "AnimationBase.h"

#include "AnimationControllerPrivate.h"
#include "CSSMutableStyleDeclaration.h"
#include "CSSPropertyLonghand.h"
#include "CSSPropertyNames.h"
#include "CString.h"
#include "CompositeAnimation.h"
#include "Document.h"
#include "EventNames.h"
#include "FloatConversion.h"
#include "Frame.h"
#include "IdentityTransformOperation.h"
#include "ImplicitAnimation.h"
#include "KeyframeAnimation.h"
#include "MatrixTransformOperation.h"
#include "Matrix3DTransformOperation.h"
#include "RenderBox.h"
#include "RenderStyle.h"
#include "UnitBezier.h"

#include <algorithm>

using namespace std;

namespace WebCore {

// The epsilon value we pass to UnitBezier::solve given that the animation is going to run over |dur| seconds. The longer the
// animation, the more precision we need in the timing function result to avoid ugly discontinuities.
static inline double solveEpsilon(double duration)
{
    return 1.0 / (200.0 * duration);
}

static inline double solveCubicBezierFunction(double p1x, double p1y, double p2x, double p2y, double t, double duration)
{
    // Convert from input time to parametric value in curve, then from
    // that to output time.
    UnitBezier bezier(p1x, p1y, p2x, p2y);
    return bezier.solve(t, solveEpsilon(duration));
}

static inline int blendFunc(const AnimationBase*, int from, int to, double progress)
{  
    return int(from + (to - from) * progress);
}

static inline double blendFunc(const AnimationBase*, double from, double to, double progress)
{  
    return from + (to - from) * progress;
}

static inline float blendFunc(const AnimationBase*, float from, float to, double progress)
{  
    return narrowPrecisionToFloat(from + (to - from) * progress);
}

static inline Color blendFunc(const AnimationBase* anim, const Color& from, const Color& to, double progress)
{
    // We need to preserve the state of the valid flag at the end of the animation
    if (progress == 1 && !to.isValid())
        return Color();

    return Color(blendFunc(anim, from.red(), to.red(), progress),
                 blendFunc(anim, from.green(), to.green(), progress),
                 blendFunc(anim, from.blue(), to.blue(), progress),
                 blendFunc(anim, from.alpha(), to.alpha(), progress));
}

static inline Length blendFunc(const AnimationBase*, const Length& from, const Length& to, double progress)
{  
    return to.blend(from, progress);
}

static inline IntSize blendFunc(const AnimationBase* anim, const IntSize& from, const IntSize& to, double progress)
{  
    return IntSize(blendFunc(anim, from.width(), to.width(), progress),
                   blendFunc(anim, from.height(), to.height(), progress));
}

static inline ShadowData* blendFunc(const AnimationBase* anim, const ShadowData* from, const ShadowData* to, double progress)
{  
    ASSERT(from && to);
    return new ShadowData(blendFunc(anim, from->x, to->x, progress), blendFunc(anim, from->y, to->y, progress), 
                          blendFunc(anim, from->blur, to->blur, progress), blendFunc(anim, from->color, to->color, progress));
}

static inline TransformOperations blendFunc(const AnimationBase* anim, const TransformOperations& from, const TransformOperations& to, double progress)
{    
    TransformOperations result;

    // If we have a transform function list, use that to do a per-function animation. Otherwise do a Matrix animation
    if (anim->isTransformFunctionListValid()) {
        unsigned fromSize = from.operations().size();
        unsigned toSize = to.operations().size();
        unsigned size = max(fromSize, toSize);
        for (unsigned i = 0; i < size; i++) {
            RefPtr<TransformOperation> fromOp = (i < fromSize) ? from.operations()[i].get() : 0;
            RefPtr<TransformOperation> toOp = (i < toSize) ? to.operations()[i].get() : 0;
            RefPtr<TransformOperation> blendedOp = toOp ? toOp->blend(fromOp.get(), progress) : (fromOp ? fromOp->blend(0, progress, true) : 0);
            if (blendedOp)
                result.operations().append(blendedOp);
            else {
                RefPtr<TransformOperation> identityOp = IdentityTransformOperation::create();
                if (progress > 0.5)
                    result.operations().append(toOp ? toOp : identityOp);
                else
                    result.operations().append(fromOp ? fromOp : identityOp);
            }
        }
    } else {
        // Convert the TransformOperations into matrices
        IntSize size = anim->renderer()->isBox() ? toRenderBox(anim->renderer())->borderBoxRect().size() : IntSize();
        TransformationMatrix fromT;
        TransformationMatrix toT;
        from.apply(size, fromT);
        to.apply(size, toT);
        
        toT.blend(fromT, progress);
        
        // Append the result
        result.operations().append(Matrix3DTransformOperation::create(toT));
    }
    return result;
}

static inline EVisibility blendFunc(const AnimationBase* anim, EVisibility from, EVisibility to, double progress)
{
    // Any non-zero result means we consider the object to be visible.  Only at 0 do we consider the object to be
    // invisible.   The invisible value we use (HIDDEN vs. COLLAPSE) depends on the specified from/to values.
    double fromVal = from == VISIBLE ? 1. : 0.;
    double toVal = to == VISIBLE ? 1. : 0.;
    if (fromVal == toVal)
        return to;
    double result = blendFunc(anim, fromVal, toVal, progress);
    return result > 0. ? VISIBLE : (to != VISIBLE ? to : from);
}

class PropertyWrapperBase;

static void addShorthandProperties();
static PropertyWrapperBase* wrapperForProperty(int propertyID);

class PropertyWrapperBase {
public:
    PropertyWrapperBase(int prop)
        : m_prop(prop)
    {
    }

    virtual ~PropertyWrapperBase() { }
    
    virtual bool isShorthandWrapper() const { return false; }
    virtual bool equals(const RenderStyle* a, const RenderStyle* b) const = 0;
    virtual void blend(const AnimationBase* anim, RenderStyle* dst, const RenderStyle* a, const RenderStyle* b, double progress) const = 0;

    int property() const { return m_prop; }

#if USE(ACCELERATED_COMPOSITING)
    virtual bool animationIsAccelerated() const { return false; }
#endif

private:
    int m_prop;
};

template <typename T>
class PropertyWrapperGetter : public PropertyWrapperBase {
public:
    PropertyWrapperGetter(int prop, T (RenderStyle::*getter)() const)
        : PropertyWrapperBase(prop)
        , m_getter(getter)
    {
    }

    virtual bool equals(const RenderStyle* a, const RenderStyle* b) const
    {
       // If the style pointers are the same, don't bother doing the test.
       // If either is null, return false. If both are null, return true.
       if (!a && !b || a == b)
           return true;
       if (!a || !b)
            return false;
        return (a->*m_getter)() == (b->*m_getter)();
    }

protected:
    T (RenderStyle::*m_getter)() const;
};

template <typename T>
class PropertyWrapper : public PropertyWrapperGetter<T> {
public:
    PropertyWrapper(int prop, T (RenderStyle::*getter)() const, void (RenderStyle::*setter)(T))
        : PropertyWrapperGetter<T>(prop, getter)
        , m_setter(setter)
    {
    }
    
    virtual void blend(const AnimationBase* anim, RenderStyle* dst, const RenderStyle* a, const RenderStyle* b, double progress) const
    {
        (dst->*m_setter)(blendFunc(anim, (a->*PropertyWrapperGetter<T>::m_getter)(), (b->*PropertyWrapperGetter<T>::m_getter)(), progress));
    }

protected:
    void (RenderStyle::*m_setter)(T);
};

#if USE(ACCELERATED_COMPOSITING)
class PropertyWrapperAcceleratedOpacity : public PropertyWrapper<float> {
public:
    PropertyWrapperAcceleratedOpacity()
        : PropertyWrapper<float>(CSSPropertyOpacity, &RenderStyle::opacity, &RenderStyle::setOpacity)
    {
    }

    virtual bool animationIsAccelerated() const { return true; }

    virtual void blend(const AnimationBase* anim, RenderStyle* dst, const RenderStyle* a, const RenderStyle* b, double progress) const
    {
        float fromOpacity = a->opacity();
        
        // This makes sure we put the object being animated into a RenderLayer during the animation
        dst->setOpacity(blendFunc(anim, (fromOpacity == 1) ? 0.999999f : fromOpacity, b->opacity(), progress));
    }
};

class PropertyWrapperAcceleratedTransform : public PropertyWrapper<const TransformOperations&> {
public:
    PropertyWrapperAcceleratedTransform()
        : PropertyWrapper<const TransformOperations&>(CSSPropertyWebkitTransform, &RenderStyle::transform, &RenderStyle::setTransform)
    {
    }
    
    virtual bool animationIsAccelerated() const { return true; }

    virtual void blend(const AnimationBase* anim, RenderStyle* dst, const RenderStyle* a, const RenderStyle* b, double progress) const
    {
        dst->setTransform(blendFunc(anim, a->transform(), b->transform(), progress));
    }
};