Source/WebCore/platform/calc/CalcExpressionBlendLength.cpp

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#include "config.h"
#include "CalcExpressionBlendLength.h"

#include "CalculationValue.h"
#include "LengthFunctions.h"
#include <wtf/text/TextStream.h>

namespace WebCore {

CalcExpressionBlendLength::CalcExpressionBlendLength(Length from, Length to, float progress)
    : CalcExpressionNode(CalcExpressionNodeType::BlendLength)
    , m_from(from)
    , m_to(to)
    , m_progress(progress)
{
    // Flatten nesting of CalcExpressionBlendLength as a speculative fix for rdar://problem/30533005.
    // CalcExpressionBlendLength is only used as a result of animation and they don't nest in normal cases.
    if (m_from.isCalculated() && m_from.calculationValue().expression().type() == CalcExpressionNodeType::BlendLength)
        m_from = downcast<CalcExpressionBlendLength>(m_from.calculationValue().expression()).from();
    if (m_to.isCalculated() && m_to.calculationValue().expression().type() == CalcExpressionNodeType::BlendLength)
        m_to = downcast<CalcExpressionBlendLength>(m_to.calculationValue().expression()).to();
}

float CalcExpressionBlendLength::evaluate(float maxValue) const
{
    return (1.0f - m_progress) * floatValueForLength(m_from, maxValue) + m_progress * floatValueForLength(m_to, maxValue);
}

bool CalcExpressionBlendLength::operator==(const CalcExpressionNode& other) const
{
    return is<CalcExpressionBlendLength>(other) && *this == downcast<CalcExpressionBlendLength>(other);
}

void CalcExpressionBlendLength::dump(TextStream& ts) const
{
    ts << "blend(" << m_from << ", " << m_to << ", " << m_progress << ")";
}

}