Method Build

modules/tools/animation_tool/src/track_builder.cc:102–151

// in the RawAnimation then the builder creates it.
template <typename _RawTrack, typename _Track>
unique_ptr<_Track> TrackBuilder::Build(const _RawTrack& _input) const {
  // Tests _raw_animation validity.
  if (!_input.Validate()) {
    return unique_ptr<_Track>();
  }

  // Everything is fine, allocates and fills the animation.
  // Nothing can fail now.
  unique_ptr<_Track> track = make_unique<_Track>();

  // Copy data to temporary prepared data structure
  typename _RawTrack::Keyframes keyframes;
  // Guessing a worst size to avoid realloc.
  const size_t worst_size =
      _input.keyframes.size() * 2 +  // * 2 in case all keys are kStep
      2;                             // + 2 for first and last keys
  keyframes.reserve(worst_size);

  // Ensure there's a key frame at the start and end of the track (required for
  // sampling).
  PatchBeginEndKeys(_input, &keyframes);

  // Fixup values, ex: successive opposite quaternions that would fail to take
  // the shortest path during the normalized-lerp.
  Fixup(&keyframes);

  // Allocates output track.
  const size_t name_len = _input.name.size();
  track->Allocate(keyframes.size(), _input.name.size());

  // Copy all keys to output.
  SKR_ASSERT(keyframes.size() == track->ratios_.size() &&
         keyframes.size() == track->values_.size() &&
         keyframes.size() <= track->steps_.size() * 8);
  memset(track->steps_.data(), 0, track->steps_.size_bytes());
  for (size_t i = 0; i < keyframes.size(); ++i) {
    const typename _RawTrack::Keyframe& src_key = keyframes[i];
    track->ratios_[i] = src_key.ratio;
    track->values_[i] = src_key.value;
    track->steps_[i / 8] |=
        (src_key.interpolation == RawTrackInterpolation::kStep) << (i & 7);
  }

  // Copy track's name.
  if (name_len) {
    strcpy(track->name_, _input.name.c_str());
  }

  return track;  // Success.
}

unique_ptr<FloatTrack> TrackBuilder::operator()(
    const RawFloatTrack& _input) const {