private static PerVertexTangentType ExtractTangents(IMgtfPerVertexDataLocator locator,
MgtfAccessor[] accessors)
{
if (locator.Tangent.HasValue)
{
var selected = accessors[locator.Tangent.Value];
var result = PerVertexTangentType.None;
if (selected.ElementType == MgtfElementType.Float && selected.NoOfComponents == 4)
{
result = PerVertexTangentType.Float4;
}
else if (selected.ElementType == MgtfElementType.Half && selected.NoOfComponents == 4)
{
result = PerVertexTangentType.Half4;
}
else
{
throw new NotSupportedException(
string.Format(
"Format not support : {0}",
selected.ElementType)
);
}
return(result);
}
else
{
return(PerVertexTangentType.None);
}
}
private static PerVertexPositionType ExtractPosition(
IMgtfPerVertexDataLocator locator,
MgtfAccessor[] accessors)
{
if (locator.Position.HasValue)
{
var selected = accessors[locator.Position.Value];
bool isInvalid = true;
var result = PerVertexPositionType.None;
if (selected.ElementType == MgtfElementType.Float)
{
if (selected.NoOfComponents == 3)
{
result = PerVertexPositionType.Float3;
isInvalid = false;
}
else if (selected.NoOfComponents == 2)
{
result = PerVertexPositionType.Float2;
isInvalid = false;
}
}
else if (selected.ElementType == MgtfElementType.Half)
{
if (selected.NoOfComponents == 3)
{
result = PerVertexPositionType.Half3;
isInvalid = false;
}
else if (selected.NoOfComponents == 2)
{
result = PerVertexPositionType.Half2;
isInvalid = false;
}
}
if (isInvalid)
{
throw new NotSupportedException(
string.Format(
"Format not support : {0}",
selected.ElementType)
);
}
return(result);
}
else
{
return(PerVertexPositionType.None);
}
}
public static PerVertexDefinition Extract(IMgtfPerVertexDataLocator locator, MgtfAccessor[] accessors)
{
return(new PerVertexDefinition
{
IndexType = ExtractIndexType(locator.Indices, accessors),
Position = ExtractPosition(locator, accessors),
Normal = ExtractNormals(locator, accessors),
Tangent = ExtractTangents(locator, accessors),
TexCoords0 = ExtractTexCoords(locator.TexCoords0, accessors),
TexCoords1 = ExtractTexCoords(locator.TexCoords1, accessors),
Weights0 = ExtractWeights(locator.Weights0, accessors),
Weights1 = ExtractWeights(locator.Weights1, accessors),
Color0 = ExtractColor(locator.Color0, accessors),
Color1 = ExtractColor(locator.Color1, accessors),
Joints0 = ExtractJoints(locator.Joints0, accessors),
Joints1 = ExtractJoints(locator.Joints1, accessors),
});
}
private static int ExtractVertices(uint vertexCount,
MgStorageBlockAllocationRequest request,
MgtfAccessor[] accessors,
MgtfBufferView[] bufferViews,
IMgtfPerVertexDataLocator locator,
out GltfInterleavedOperation[] vertexCopies)
{
var totalSize = 0UL;
var vertexFields = new int?[]
{
locator.Position,
locator.Normal,
locator.Tangent,
locator.TexCoords0,
locator.TexCoords1,
locator.Color0,
locator.Color1,
locator.Joints0,
locator.Joints1,
locator.Weights0,
locator.Weights1,
};
var DEFAULT_PADDING_BYTE_STRIDE = new uint[]
{
12U,
12U,
16U,
8U,
8U,
16U,
16U,
4U,
4U,
16U,
16U,
};
var copyOps = new List <GltfInterleavedOperation>();
var vertexBufferStride = 0U;
for (var i = 0; i < vertexFields.Length; i += 1)
{
var field = vertexFields[i];
if (field.HasValue)
{
var selected = accessors[field.Value];
var op = GenerateCopyOperation(selected, bufferViews);
copyOps.Add(op);
vertexBufferStride += op.ByteStride;
totalSize += selected.TotalByteSize;
}
else
{
vertexBufferStride += DEFAULT_PADDING_BYTE_STRIDE[i];
totalSize += vertexCount * DEFAULT_PADDING_BYTE_STRIDE[i];
}
}
foreach (var op in copyOps)
{
op.DstStride = vertexBufferStride;
}
var vertexInfo = new MgStorageBlockAllocationInfo
{
MemoryPropertyFlags = MgMemoryPropertyFlagBits.HOST_COHERENT_BIT,
Usage = MgBufferUsageFlagBits.VERTEX_BUFFER_BIT,
ElementByteSize = vertexBufferStride,
Size = totalSize,
};
vertexCopies = copyOps.ToArray();
return(request.Insert(vertexInfo));
}