Method ScaleTimeRemap

src/rendering/layers/PAGImageLayer.cpp:378–434

}

Frame PAGImageLayer::ScaleTimeRemap(AnimatableProperty<float>* property,
                                    const TimeRange& visibleRange, double frameScale,
                                    Frame fileEndFrame) {
  float minValue = FLT_MAX;
  float maxValue = 0;
  auto& keyframes = property->keyframes;
  for (int i = static_cast<int>(keyframes.size() - 1); i >= 0; i--) {
    auto& keyframe = keyframes[i];
    keyframe->startTime =
        visibleRange.start + static_cast<Frame>(round(keyframe->startTime * frameScale));
    auto duration = keyframe->endTime - keyframe->startTime + 1;
    // 由于是闭区间，计算完后需要-1
    keyframe->endTime = visibleRange.start +
                        static_cast<Frame>(round((keyframe->startTime + duration) * frameScale)) -
                        1;
    keyframe->startValue = static_cast<Frame>(round(keyframe->startValue * frameScale));
    auto valueLength = keyframe->endValue - keyframe->startValue + 1;
    // 由于是闭区间，计算完后需要-1
    keyframe->endValue =
        static_cast<Frame>(round((keyframe->startValue + valueLength) * frameScale)) - 1;
    // 由于startTime和endTime都是帧号，因此当startTime == fileEndFrame 和 endTime == 0都有意义
    if (keyframe->startTime > fileEndFrame) {
      delete keyframe;
      keyframes.erase(keyframes.begin() + i);
      continue;
    }
    if (keyframe->endTime < 0) {
      delete keyframe;
      keyframes.erase(keyframes.begin() + i);
      continue;
    }
    if (keyframe->endTime > fileEndFrame) {
      CutKeyframe(keyframe, fileEndFrame, false);
    }
    if (keyframe->startTime < 0) {
      CutKeyframe(keyframe, 0, true);
    }
    minValue = std::round(std::min(keyframe->startValue, minValue));
    minValue = std::round(std::min(keyframe->endValue, minValue));
    maxValue = std::round(std::max(keyframe->startValue, maxValue));
    maxValue = std::round(std::max(keyframe->endValue, maxValue));
  }
  for (auto& keyframe : keyframes) {
    keyframe->startValue -= minValue;
    keyframe->endValue -= minValue;
  }
  // 当keyframes所有的区间都在File的显示区间之外时，补一个keyFrame，防止后续计算错误。
  if (keyframes.size() == 0) {
    auto newKeyframe = CreateKeyframe(visibleRange.start, visibleRange.end, 0,
                                      visibleRange.end - visibleRange.start);
    keyframes.push_back(newKeyframe);
    newKeyframe->initialize();
    maxValue = visibleRange.end - visibleRange.start;
    minValue = 0;
  }
  return (maxValue - minValue + 1);
}