third_party/WebKit/Source/core/animation/InterpolationEffect.cpp

// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "core/animation/InterpolationEffect.h"

#include "platform/animation/AnimationUtilities.h"

namespace blink {

void InterpolationEffect::getActiveInterpolations(
    double fraction,
    double iterationDuration,
    Vector<RefPtr<Interpolation>>& result) const {
  size_t existingSize = result.size();
  size_t resultIndex = 0;

  for (const auto& record : m_interpolations) {
    if (fraction >= record.m_applyFrom && fraction < record.m_applyTo) {
      RefPtr<Interpolation> interpolation = record.m_interpolation;
      double recordLength = record.m_end - record.m_start;
      double localFraction =
          recordLength ? (fraction - record.m_start) / recordLength : 0.0;
      if (record.m_easing)
        localFraction = record.m_easing->evaluate(
            localFraction, accuracyForDuration(iterationDuration));
      interpolation->interpolate(0, localFraction);
      if (resultIndex < existingSize)
        result[resultIndex++] = interpolation;
      else
        result.append(interpolation);
    }
  }
  if (resultIndex < existingSize)
    result.shrink(resultIndex);
}

void InterpolationEffect::addInterpolationsFromKeyframes(
    PropertyHandle property,
    const Keyframe::PropertySpecificKeyframe& keyframeA,
    const Keyframe::PropertySpecificKeyframe& keyframeB,
    double applyFrom,
    double applyTo) {
  addInterpolation(keyframeA.createInterpolation(property, keyframeB),
                   &keyframeA.easing(), keyframeA.offset(), keyframeB.offset(),
                   applyFrom, applyTo);
}

}  // namespace blink