Method BuildContentTimeRemap

src/rendering/layers/PAGImageLayer.cpp:437–466

输出的时间轴不包含startTime

// 输出的时间轴不包含startTime
void PAGImageLayer::BuildContentTimeRemap(AnimatableProperty<float>* property, PAGFile* fileOwner,
                                          const TimeRange& visibleRange, double frameScale) {
  auto fileDuration = fileOwner->frameDuration();
  auto fileStretchedDuration = fileOwner->stretchedFrameDuration();
  auto hasRepeat = (fileOwner->_timeStretchMode == PAGTimeStretchMode::Repeat ||
                    fileOwner->_timeStretchMode == PAGTimeStretchMode::RepeatInverted) &&
                   (fileDuration < fileStretchedDuration);
  auto fileEndFrame = hasRepeat ? fileDuration - 1 : fileStretchedDuration - 1;
  auto scaleDuration = ScaleTimeRemap(property, visibleRange, frameScale, fileEndFrame);
  auto& keyframes = property->keyframes;
  // 补齐头尾的空缺。
  auto firstKeyframe = keyframes.front();
  if (firstKeyframe->startTime > 0) {
    auto newKeyframe = CreateKeyframe(0, firstKeyframe->startTime, firstKeyframe->startValue,
                                      firstKeyframe->startValue);
    keyframes.insert(keyframes.begin(), newKeyframe);
    newKeyframe->initialize();
  }
  auto lastKeyframe = keyframes.back();
  if (lastKeyframe->endTime < fileEndFrame) {
    auto newKeyframe = CreateKeyframe(lastKeyframe->endTime, fileEndFrame, lastKeyframe->endValue,
                                      lastKeyframe->endValue);
    keyframes.push_back(newKeyframe);
    newKeyframe->initialize();
  }
  if (hasRepeat) {
    // 处理file存在repeat拉伸的情况。
    ExpandPropertyByRepeat(property, fileOwner, scaleDuration);
  }
}

TimeRange PAGImageLayer::getVisibleRangeInFile() {
  TimeRange timeRange = {};