Source/core/animation/AnimatableLength.cpp

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

#include "core/css/CSSPrimitiveValueMappings.h"
#include "platform/CalculationValue.h"
#include "platform/animation/AnimationUtilities.h"

namespace WebCore {

PassRefPtrWillBeRawPtr<AnimatableLength> AnimatableLength::create(CSSValue* value)
{
    ASSERT(canCreateFrom(value));
    if (value->isPrimitiveValue()) {
        CSSPrimitiveValue* primitiveValue = WebCore::toCSSPrimitiveValue(value);
        const CSSCalcValue* calcValue = primitiveValue->cssCalcValue();
        if (calcValue)
            return create(calcValue->expressionNode(), primitiveValue);
        CSSPrimitiveValue::LengthUnitType unitType;
        bool isPrimitiveLength = CSSPrimitiveValue::unitTypeToLengthUnitType(primitiveValue->primitiveType(), unitType);
        ASSERT_UNUSED(isPrimitiveLength, isPrimitiveLength);
        const double scale = CSSPrimitiveValue::conversionToCanonicalUnitsScaleFactor(primitiveValue->primitiveType());
        return create(primitiveValue->getDoubleValue() * scale, unitType, primitiveValue);
    }

    if (value->isCalcValue())
        return create(toCSSCalcValue(value)->expressionNode());

    ASSERT_NOT_REACHED();
    return nullptr;
}

bool AnimatableLength::canCreateFrom(const CSSValue* value)
{
    ASSERT(value);
    if (value->isPrimitiveValue()) {
        const CSSPrimitiveValue* primitiveValue = WebCore::toCSSPrimitiveValue(value);
        if (primitiveValue->cssCalcValue())
            return true;

        CSSPrimitiveValue::LengthUnitType type;
        // Only returns true if the type is a primitive length unit.
        return CSSPrimitiveValue::unitTypeToLengthUnitType(primitiveValue->primitiveType(), type);
    }
    return value->isCalcValue();
}

PassRefPtrWillBeRawPtr<CSSValue> AnimatableLength::toCSSValue(NumberRange range) const
{
    return toCSSPrimitiveValue(range);
}

Length AnimatableLength::toLength(const CSSToLengthConversionData& conversionData, NumberRange range) const
{
    // Avoid creating a CSSValue in the common cases
    if (m_lengthUnitType == CSSPrimitiveValue::UnitTypePixels)
        return Length(clampedNumber(range) * conversionData.zoom(), Fixed);
    if (m_lengthUnitType == CSSPrimitiveValue::UnitTypePercentage)
        return Length(clampedNumber(range), Percent);

    return toCSSPrimitiveValue(range)->convertToLength<AnyConversion>(conversionData);
}

PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableLength::interpolateTo(const AnimatableValue* value, double fraction) const
{
    const AnimatableLength* length = toAnimatableLength(value);
    CSSPrimitiveValue::LengthUnitType type = commonUnitType(length);
    if (!isCalc(type))
        return AnimatableLength::create(blend(m_lengthValue, length->m_lengthValue, fraction), type);
    return AnimatableLength::create(scale(1 - fraction).get(), length->scale(fraction).get());
}

bool AnimatableLength::equalTo(const AnimatableValue* value) const
{
    const AnimatableLength* length = toAnimatableLength(value);
    if (m_lengthUnitType != length->m_lengthUnitType)
        return false;
    if (isCalc())
        return m_calcExpression == length->m_calcExpression || m_calcExpression->equals(*length->m_calcExpression);
    return m_lengthValue == length->m_lengthValue;
}

PassRefPtrWillBeRawPtr<CSSCalcExpressionNode> AnimatableLength::toCSSCalcExpressionNode() const
{
    if (isCalc())
        return m_calcExpression;
    return CSSCalcValue::createExpressionNode(toCSSPrimitiveValue(AllValues), m_lengthValue == trunc(m_lengthValue));
}

static bool isCompatibleWithRange(const CSSPrimitiveValue* primitiveValue, NumberRange range)
{
    ASSERT(primitiveValue);
    if (range == AllValues)
        return true;
    if (primitiveValue->isCalculated())
        return primitiveValue->cssCalcValue()->permittedValueRange() == ValueRangeNonNegative;
    return primitiveValue->getDoubleValue() >= 0;
}

PassRefPtrWillBeRawPtr<CSSPrimitiveValue> AnimatableLength::toCSSPrimitiveValue(NumberRange range) const
{
    if (!m_cachedCSSPrimitiveValue || !isCompatibleWithRange(m_cachedCSSPrimitiveValue.get(), range)) {
        if (isCalc())
            m_cachedCSSPrimitiveValue = CSSPrimitiveValue::create(CSSCalcValue::create(m_calcExpression, range == AllValues ? ValueRangeAll : ValueRangeNonNegative));
        else
            m_cachedCSSPrimitiveValue = CSSPrimitiveValue::create(clampedNumber(range), static_cast<CSSPrimitiveValue::UnitTypes>(CSSPrimitiveValue::lengthUnitTypeToUnitType(m_lengthUnitType)));
    }
    return m_cachedCSSPrimitiveValue;
}

PassRefPtrWillBeRawPtr<AnimatableLength> AnimatableLength::scale(double factor) const
{
    if (isCalc()) {
        return AnimatableLength::create(CSSCalcValue::createExpressionNode(
            m_calcExpression,
            CSSCalcValue::createExpressionNode(CSSPrimitiveValue::create(factor, CSSPrimitiveValue::CSS_NUMBER)),
            CalcMultiply));
    }
    return AnimatableLength::create(m_lengthValue * factor, m_lengthUnitType);
}

void AnimatableLength::trace(Visitor* visitor)
{
    visitor->trace(m_calcExpression);
    visitor->trace(m_cachedCSSPrimitiveValue);
}

} // namespace WebCore