public static void GetVertexAndIndexData(ModelGeometry modelGeometry, out VertexPositionNormalTexture[] vertexData, out short[] indexData)
{
if (modelGeometry.Meshes.Length != 1) throw new NotImplementedException("Multiple meshes");
var mesh = modelGeometry.Meshes[0];
if (mesh.MeshParts.Length != 1) throw new NotImplementedException("Multiple mesh parts");
var meshPartToworldMatrix = Matrix.Identity;
for (var bone = mesh.ParentBone; bone != null; bone = bone.Parent) meshPartToworldMatrix *= bone.Transform;
var meshPart = mesh.MeshParts[0];
vertexData = meshPart.VertexBuffer.Vertices
.Select(vertex => new VertexPositionNormalTexture(
position: Vector3.Transform(vertex.Position, meshPartToworldMatrix),
normal: Vector3.TransformNormal(vertex.Normal, meshPartToworldMatrix),
textureCoordinate: vertex.TextureCoordinate))
.ToArray();
indexData = new short[meshPart.PrimitiveCount * 3];
Array.Copy(meshPart.IndexBuffer.Indices, meshPart.StartIndex, indexData, 0, indexData.Length);
}
protected override void CopyAbsoluteBoneTransformsTo(ModelGeometry skeleton, Matrix[] transforms)
{
if (transforms == null) throw new ArgumentNullException("Null transformation matrix array");
if (transforms.Length < skeleton.Bones.Length) throw new ArgumentException("Too short transformation matrix array");
float[] tailTurnDeltas = new float[skeleton.Bones.Length];
float prevTailTurn = Rotation + DrawRotationOffset;
foreach (int i in _tailIndices)
{
tailTurnDeltas[i] = MathHelper.WrapAngle(_tailTurns[i].Current - prevTailTurn);
prevTailTurn = _tailTurns[i].Current;
}
foreach (var bone in skeleton.Bones)
{
if (bone.Parent == null)
transforms[bone.Index] = bone.Transform;
else
{
if (bone.Parent.Index >= bone.Index) throw new Exception("Unexpected situation: bone parent doesn't precede the bone itself");
if (_tailPhases[bone.Index] < 0)
transforms[bone.Index] = bone.Transform * transforms[bone.Parent.Index];
else
{
float wigglePhase = _wiggleMainPhase + _tailPhases[bone.Index];
float turnDamping = 1 - Math.Abs(tailTurnDeltas[bone.Index]) / MAX_TAIL_TURN; // wiggle less when bent
float tailAmplitude = MIN_TAIL_AMPLITUDE + turnDamping * (_tailAmplitudes[bone.Index] - MIN_TAIL_AMPLITUDE);
float wiggleAngle = tailTurnDeltas[bone.Index] + tailAmplitude * (float)Math.Sin(wigglePhase);
var extraTransform = Matrix.CreateRotationZ(wiggleAngle);
transforms[bone.Index] = extraTransform * bone.Transform * transforms[bone.Parent.Index];
}
}
}
}
