ImportGeometryFromAssimp2JsonMesh function

GeometryBuilder ImportGeometryFromAssimp2JsonMesh(Map<String, dynamic> mesh, List<Bone> skeleton)

Implementation

GeometryBuilder ImportGeometryFromAssimp2JsonMesh(
    Map<String, dynamic> mesh, List<Bone> skeleton) {
  GeometryBuilder gb = GeometryBuilder();
  String name = mesh['name'];

  assert(mesh.containsKey("vertices"), "no vertices");
  gb.AddVertices(ConvertToVector3List(mesh['vertices']));
  if (mesh.containsKey("normals")) {
    gb.EnableAttribute(aNormal);
    gb.AddAttributesVector3(aNormal, ConvertToVector3List(mesh['normals']));
  }
  if (mesh.containsKey("texturecoords")) {
    assert(mesh["texturecoords"].length == 1);
    gb.EnableAttribute(aTexUV);
    gb.AddAttributesVector2(
        aTexUV, ConvertToVector2List(mesh['texturecoords'][0]));
  }
  if (mesh.containsKey("tangents")) {
    gb.EnableAttribute(aTangent);
    gb.AddAttributesVector3(aTangent, ConvertToVector3List(mesh['tangents']));
  }
  if (mesh.containsKey("bitangents")) {
    gb.EnableAttribute(aBitangent);
    gb.AddAttributesVector3(
        aBitangent, ConvertToVector3List(mesh['bitangents']));
  }
  List<List<int>> faces = _ListIntify(mesh['faces']);
  assert(faces != null, "no faces");
  for (List<int> f in faces) {
    assert(f.length == 3);
    gb.AddFace3(f[0], f[1], f[2]);
  }

  if (skeleton != null) {
    Map<String, Bone> name2bone = <String, Bone>{};
    skeleton.forEach((b) => name2bone[b.boneName] = b);
    final int n = mesh['normals'].length ~/ 3;
    List<VM.Vector4> indices = List.generate(n, (i) => VM.Vector4.zero());
    List<VM.Vector4> weights = List.generate(n, (i) => VM.Vector4.zero());
    for (Map<String, dynamic> b in mesh["bones"]) {
      assert(name2bone.containsKey(b["name"]));
      final Bone bone = name2bone[b["name"]] as Bone;
      // Note: Surprising side-effect
      bone.offsetTransform.copyFromArray(_Floatify(b["offsetmatrix"]));
      bone.offsetTransform.transpose();
      if (b.containsKey("weights")) {
        final double boneIndex = bone.boneIndex.toDouble();

        for (List w in b["weights"]) {
          final int vertex = w[0];
          int pos;
          for (pos = 0; pos < 4; ++pos) {
            if (weights[vertex][pos] == 0.0) break;
          }
          assert(pos != 4);
          weights[vertex][pos] = w[1].toDouble();
          indices[vertex][pos] = boneIndex;
        }
      }
    }
    gb.EnableAttribute(aBoneIndex);
    gb.EnableAttribute(aBoneWeight);
    gb.AddAttributesVector4(aBoneIndex, indices);
    gb.AddAttributesVector4(aBoneWeight, weights);
  }

  print("mesh ${name} ${gb} ${mesh.keys}");
  return gb;
}