/// <summary>
/// Propagate our global transform to the sub meshes, recomputing their bounding boxes
/// </summary>
private void UpdateSubMeshes()
{
Helpers.TransformBoundingBox(ref _localBoundingBox, ref _transform, out _globalBoundingBox);
if (_model != null)
{
for (int i = 0; i < _model.Bones.Count; i++)
{
_transforms[i] = _model.Bones[i].Transform * _transform;
}
for (int i = 0; i < _subMeshes.Count; i++)
{
SubMesh subMesh = _subMeshes[i];
//compute the global transform for this submesh
subMesh.GlobalTransform = _transforms[_model.Meshes[subMesh._modelIndex].ParentBone.Index];
MeshMetadata.SubMeshMetadata metadata = subMesh._metadata;
BoundingBox source = metadata.BoundingBox;
//compute the global bounding box
Helpers.TransformBoundingBox(ref source, ref _transform, out subMesh.GlobalBoundingBox);
subMesh.GlobalBoundingSphere = BoundingSphere.CreateFromBoundingBox(subMesh.GlobalBoundingBox);
}
}
}
private BoundingBox ComputeBoundingBox(NodeContent input, ref BoundingBox aabb, MeshMetadata metadata)
{
BoundingBox boundingBox;
if (input is MeshContent)
{
MeshContent mc = (MeshContent)input;
MeshHelper.TransformScene(mc, mc.Transform);
mc.Transform = Matrix.Identity;
boundingBox = BoundingBox.CreateFromPoints(mc.Positions);
//create sub mesh information
MeshMetadata.SubMeshMetadata subMeshMetadata = new MeshMetadata.SubMeshMetadata();
subMeshMetadata.BoundingBox = boundingBox;
subMeshMetadata.RenderQueue = _renderQueue;
subMeshMetadata.CastShadows = CastShadows;
metadata.AddSubMeshMetadata(subMeshMetadata);
if (metadata.SubMeshesMetadata.Count > 1)
boundingBox = BoundingBox.CreateMerged(boundingBox, aabb);
}
else
{
boundingBox = aabb;
}
foreach (NodeContent c in input.Children)
{
boundingBox = BoundingBox.CreateMerged(boundingBox, ComputeBoundingBox(c, ref boundingBox, metadata));
}
return boundingBox;
}