private static GltfInterleavedOperation GenerateCopyOperation(MgtfAccessor accessor, MgtfBufferView[] bufferViews)
{
if (!accessor.BufferView.HasValue)
{
throw new InvalidOperationException("unable to locate bufferview");
}
var view = bufferViews[accessor.BufferView.Value];
var op = new GltfInterleavedOperation
{
BufferIndex = view.BufferIndex,
Count = accessor.ElementCount,
SrcOffset = (ulong)(view.BufferOffset + accessor.ViewOffset),
TotalSize = (uint)(accessor.ElementCount * accessor.NoOfComponents * accessor.ElementByteSize),
ByteStride = (view.ByteStride.HasValue)
? (uint)view.ByteStride.Value
: accessor.NoOfComponents * accessor.ElementByteSize,
};
return(op);
}
private GltfPrimitiveStorageLocation[] AllocateMeshes(
MgStorageBlockAllocationRequest request,
MgtfMesh[] meshes,
MgtfAccessor[] accessors,
MgtfBufferView[] bufferViews)
{
var noOfMeshes = meshes != null ? meshes.Length : 0;
var locations = new List <GltfPrimitiveStorageLocation>();
for (var i = 0; i < noOfMeshes; i += 1)
{
var mesh = meshes[i];
var noOfPrimitives = mesh.Primitives != null
? mesh.Primitives.Length
: 0;
for (var j = 0; j < noOfPrimitives; j += 1)
{
var primitive = mesh.Primitives[j];
var locator = primitive.VertexLocations;
int?indexLocation = null;
GltfInterleavedOperation indexCopy = null;
if (locator.Indices.HasValue)
{
var accessor = accessors[locator.Indices.Value];
indexCopy = GenerateCopyOperation(accessor, bufferViews);
indexCopy.DstStride = accessor.ElementByteSize;
indexLocation = request.Insert(GetIndexAllocation(accessor));
}
var vertexLocation = ExtractVertices(
primitive.VertexCount,
request,
accessors,
bufferViews,
locator,
out GltfInterleavedOperation[] vertexCopies);
var copyOperations = new List <GltfInterleavedOperation>();
if (indexCopy != null)
{
copyOperations.Add(indexCopy);
}
copyOperations.AddRange(vertexCopies);
var location = new GltfPrimitiveStorageLocation
{
Mesh = i,
MeshPrimitive = j,
FinalDefinition = PadVertexDefinition(primitive.InitialDefinition),
Index = indexLocation,
Vertex = vertexLocation,
CopyOperations = copyOperations.ToArray(),
};
locations.Add(location);
}
}
return(locations.ToArray());
}
