Source/core/animation/AnimatableRepeatable.cpp

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#include "config.h"
#include "core/animation/AnimatableRepeatable.h"

#include "wtf/MathExtras.h"

namespace WebCore {

bool AnimatableRepeatable::usesDefaultInterpolationWith(const AnimatableValue* value) const
{
    const WillBeHeapVector<RefPtrWillBeMember<AnimatableValue> >& fromValues = m_values;
    const WillBeHeapVector<RefPtrWillBeMember<AnimatableValue> >& toValues = toAnimatableRepeatable(value)->m_values;
    ASSERT(!fromValues.isEmpty() && !toValues.isEmpty());
    size_t size = lowestCommonMultiple(fromValues.size(), toValues.size());
    ASSERT(size > 0);
    for (size_t i = 0; i < size; ++i) {
        const AnimatableValue* from = fromValues[i % fromValues.size()].get();
        const AnimatableValue* to = toValues[i % toValues.size()].get();
        // Spec: If a pair of values cannot be interpolated, then the lists are not interpolable.
        if (AnimatableValue::usesDefaultInterpolation(from, to))
            return true;
    }
    return false;
}

bool AnimatableRepeatable::interpolateLists(const WillBeHeapVector<RefPtrWillBeMember<AnimatableValue> >& fromValues, const WillBeHeapVector<RefPtrWillBeMember<AnimatableValue> >& toValues, double fraction, WillBeHeapVector<RefPtrWillBeMember<AnimatableValue> >& interpolatedValues)
{
    // Interpolation behaviour spec: http://www.w3.org/TR/css3-transitions/#animtype-repeatable-list
    ASSERT(interpolatedValues.isEmpty());
    ASSERT(!fromValues.isEmpty() && !toValues.isEmpty());
    size_t size = lowestCommonMultiple(fromValues.size(), toValues.size());
    ASSERT(size > 0);
    for (size_t i = 0; i < size; ++i) {
        const AnimatableValue* from = fromValues[i % fromValues.size()].get();
        const AnimatableValue* to = toValues[i % toValues.size()].get();
        // Spec: If a pair of values cannot be interpolated, then the lists are not interpolable.
        if (AnimatableValue::usesDefaultInterpolation(from, to))
            return false;
        interpolatedValues.append(interpolate(from, to, fraction));
    }
    return true;
}

PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableRepeatable::interpolateTo(const AnimatableValue* value, double fraction) const
{
    WillBeHeapVector<RefPtrWillBeMember<AnimatableValue> > interpolatedValues;
    bool success = interpolateLists(m_values, toAnimatableRepeatable(value)->m_values, fraction, interpolatedValues);
    if (success)
        return create(interpolatedValues);
    return defaultInterpolateTo(this, value, fraction);
}

bool AnimatableRepeatable::equalTo(const AnimatableValue* value) const
{
    const WillBeHeapVector<RefPtrWillBeMember<AnimatableValue> >& otherValues = toAnimatableRepeatable(value)->m_values;
    if (m_values.size() != otherValues.size())
        return false;
    for (size_t i = 0; i < m_values.size(); ++i) {
        if (!m_values[i]->equals(otherValues[i].get()))
            return false;
    }
    return true;
}

void AnimatableRepeatable::trace(Visitor* visitor)
{
    visitor->trace(m_values);
    AnimatableValue::trace(visitor);
}

} // namespace WebCore