protected virtual void BuildMeshAttributes(MeshPrimitive primitive, int meshID, int primitiveIndex)
{
if (_assetCache.MeshCache[meshID][primitiveIndex].MeshAttributes.Count == 0)
{
Dictionary <string, AttributeAccessor> attributeAccessors = new Dictionary <string, AttributeAccessor>(primitive.Attributes.Count + 1);
foreach (var attributePair in primitive.Attributes)
{
AttributeAccessor AttributeAccessor = new AttributeAccessor()
{
AccessorId = attributePair.Value,
Buffer = _assetCache.BufferCache[attributePair.Value.Value.BufferView.Value.Buffer.Id]
};
attributeAccessors[attributePair.Key] = AttributeAccessor;
}
if (primitive.Indices != null)
{
AttributeAccessor indexBuilder = new AttributeAccessor()
{
AccessorId = primitive.Indices,
Buffer = _assetCache.BufferCache[primitive.Indices.Value.BufferView.Value.Buffer.Id]
};
attributeAccessors[SemanticProperties.INDICES] = indexBuilder;
}
GLTFHelpers.BuildMeshAttributes(ref attributeAccessors);
// Flip vectors and triangles to the Unity coordinate system.
if (attributeAccessors.ContainsKey(SemanticProperties.POSITION))
{
NumericArray resultArray = attributeAccessors[SemanticProperties.POSITION].AccessorContent;
resultArray.AsVertices = GLTFUnityHelpers.FlipVectorArrayHandedness(resultArray.AsVertices);
attributeAccessors[SemanticProperties.POSITION].AccessorContent = resultArray;
}
if (attributeAccessors.ContainsKey(SemanticProperties.INDICES))
{
NumericArray resultArray = attributeAccessors[SemanticProperties.INDICES].AccessorContent;
resultArray.AsTriangles = GLTFUnityHelpers.FlipFaces(resultArray.AsTriangles);
attributeAccessors[SemanticProperties.INDICES].AccessorContent = resultArray;
}
if (attributeAccessors.ContainsKey(SemanticProperties.NORMAL))
{
NumericArray resultArray = attributeAccessors[SemanticProperties.NORMAL].AccessorContent;
resultArray.AsNormals = GLTFUnityHelpers.FlipVectorArrayHandedness(resultArray.AsNormals);
attributeAccessors[SemanticProperties.NORMAL].AccessorContent = resultArray;
}
// TexCoord goes from 0 to 3 to match GLTFHelpers.BuildMeshAttributes
for (int i = 0; i < 4; i++)
{
if (attributeAccessors.ContainsKey(SemanticProperties.TexCoord(i)))
{
NumericArray resultArray = attributeAccessors[SemanticProperties.TexCoord(i)].AccessorContent;
resultArray.AsTexcoords = GLTFUnityHelpers.FlipTexCoordArrayV(resultArray.AsTexcoords);
attributeAccessors[SemanticProperties.TexCoord(i)].AccessorContent = resultArray;
}
}
if (attributeAccessors.ContainsKey(SemanticProperties.TANGENT))
{
NumericArray resultArray = attributeAccessors[SemanticProperties.TANGENT].AccessorContent;
resultArray.AsTangents = GLTFUnityHelpers.FlipVectorArrayHandedness(resultArray.AsTangents);
attributeAccessors[SemanticProperties.TANGENT].AccessorContent = resultArray;
}
_assetCache.MeshCache[meshID][primitiveIndex].MeshAttributes = attributeAccessors;
}
}
// a mesh *might* decode to multiple prims if there are submeshes
private MeshPrimitive[] ExportPrimitive(GameObject gameObject)
{
var filter = gameObject.GetComponent <MeshFilter>();
var meshObj = filter.sharedMesh;
var renderer = gameObject.GetComponent <MeshRenderer>();
var materialsObj = renderer.sharedMaterials;
var prims = new MeshPrimitive[meshObj.subMeshCount];
// don't export any more accessors if this mesh is already exported
MeshPrimitive[] primVariations;
if (_meshToPrims.TryGetValue(meshObj, out primVariations) &&
meshObj.subMeshCount == primVariations.Length)
{
for (var i = 0; i < primVariations.Length; i++)
{
prims[i] = new MeshPrimitive(primVariations[i], _root)
{
Material = ExportMaterial(materialsObj[i])
};
}
return(prims);
}
AccessorId aPosition = null, aNormal = null, aTangent = null,
aTexcoord0 = null, aTexcoord1 = null, aColor0 = null;
aPosition = ExportAccessor(GLTFUnityHelpers.FlipVectorArrayHandedness(meshObj.vertices));
if (meshObj.normals.Length != 0)
{
aNormal = ExportAccessor(GLTFUnityHelpers.FlipVectorArrayHandedness(meshObj.normals));
}
if (meshObj.tangents.Length != 0)
{
aTangent = ExportAccessor(GLTFUnityHelpers.FlipVectorArrayHandedness(meshObj.tangents));
}
if (meshObj.uv.Length != 0)
{
aTexcoord0 = ExportAccessor(GLTFUnityHelpers.FlipTexCoordArrayV(meshObj.uv));
}
if (meshObj.uv2.Length != 0)
{
aTexcoord1 = ExportAccessor(GLTFUnityHelpers.FlipTexCoordArrayV(meshObj.uv2));
}
if (meshObj.colors.Length != 0)
{
aColor0 = ExportAccessor(meshObj.colors);
}
MaterialId lastMaterialId = null;
for (var submesh = 0; submesh < meshObj.subMeshCount; submesh++)
{
var primitive = new MeshPrimitive();
var triangles = meshObj.GetTriangles(submesh);
primitive.Indices = ExportAccessor(GLTFUnityHelpers.FlipFaces(triangles), true);
primitive.Attributes = new Dictionary <string, AccessorId>();
primitive.Attributes.Add(SemanticProperties.POSITION, aPosition);
if (aNormal != null)
{
primitive.Attributes.Add(SemanticProperties.NORMAL, aNormal);
}
if (aTangent != null)
{
primitive.Attributes.Add(SemanticProperties.TANGENT, aTangent);
}
if (aTexcoord0 != null)
{
primitive.Attributes.Add(SemanticProperties.TexCoord(0), aTexcoord0);
}
if (aTexcoord1 != null)
{
primitive.Attributes.Add(SemanticProperties.TexCoord(1), aTexcoord1);
}
if (aColor0 != null)
{
primitive.Attributes.Add(SemanticProperties.Color(0), aColor0);
}
if (submesh < materialsObj.Length)
{
primitive.Material = ExportMaterial(materialsObj[submesh]);
lastMaterialId = primitive.Material;
}
else
{
primitive.Material = lastMaterialId;
}
prims[submesh] = primitive;
}
_meshToPrims[meshObj] = prims;
return(prims);
}