Method operator()

modules/tools/animation_tool/src/skeleton_builder.cc:77–153

Validates the RawSkeleton and fills a Skeleton. Uses RawSkeleton::IterateJointsDF to traverse in DAG depth-first order. Building skeleton hierarchy in depth first order make it easier to iterate a skeleton sub-hierarchy.

// Building skeleton hierarchy in depth first order make it easier to iterate a
// skeleton sub-hierarchy.
unique_ptr<ozz::animation::Skeleton> SkeletonBuilder::operator()(
    const RawSkeleton& _raw_skeleton) const {
  // Tests _raw_skeleton validity.
  if (!_raw_skeleton.Validate()) {
    return nullptr;
  }

  // Everything is fine, allocates and fills the skeleton.
  // Will not fail.
  unique_ptr<ozz::animation::Skeleton> skeleton = make_unique<Skeleton>();
  const int num_joints = _raw_skeleton.num_joints();

  // Iterates through all the joint of the raw skeleton and fills a sorted joint
  // list.
  // Iteration order defines runtime skeleton joint ordering.
  JointLister lister(num_joints);
  IterateJointsDF<JointLister&>(_raw_skeleton, lister);
  SKR_ASSERT(static_cast<int>(lister.linear_joints.size()) == num_joints);

  // Computes name's buffer size.
  size_t chars_size = 0;
  for (int i = 0; i < num_joints; ++i) {
    const RawSkeleton::Joint& current = *lister.linear_joints[i].joint;
    chars_size += (current.name.size() + 1) * sizeof(char);
  }

  // Allocates all skeleton members.
  char* cursor = skeleton->Allocate(chars_size, num_joints);

  // Copy names. All names are allocated in a single buffer. Only the first name
  // is set, all other names array entries must be initialized.
  for (int i = 0; i < num_joints; ++i) {
    const RawSkeleton::Joint& current = *lister.linear_joints[i].joint;
    skeleton->joint_names_[i] = cursor;
    strcpy(cursor, current.name.c_str());
    cursor += (current.name.size() + 1) * sizeof(char);
  }

  // Transfers sorted joints hierarchy to the new skeleton.
  for (int i = 0; i < num_joints; ++i) {
    skeleton->joint_parents_[i] = lister.linear_joints[i].parent;
  }

  // Transfers t-poses.
  const math::SimdFloat4 w_axis = math::simd_float4::w_axis();
  const math::SimdFloat4 zero = math::simd_float4::zero();
  const math::SimdFloat4 one = math::simd_float4::one();

  for (int i = 0; i < skeleton->num_soa_joints(); ++i) {
    math::SimdFloat4 translations[4];
    math::SimdFloat4 scales[4];
    math::SimdFloat4 rotations[4];
    for (int j = 0; j < 4; ++j) {
      if (i * 4 + j < num_joints) {
        const RawSkeleton::Joint& src_joint =
            *lister.linear_joints[i * 4 + j].joint;
        translations[j] =
            math::simd_float4::Load3PtrU(&src_joint.transform.translation.x);