// Returns meshes in meters, in the proper basis, with proper winding
static IEnumerable <ModelMesh> GetModelMeshesFromGameObject(GameObject obj,
SceneStatePayload payload,
bool reverseWinding)
{
int i = -1;
string exportName = obj.name;
foreach (MeshData data in VisitMeshes(obj))
{
i++;
var mesh = data.mesh;
for (int sm = 0; sm < mesh.subMeshCount; sm++)
{
var exportableMaterial = GetMaterialForMeshData(data);
// TODO: The geometry pools could be aggregated, for faster downstream rendering.
var geo = new GeometryPool();
geo.Layout = exportableMaterial.VertexLayout;
geo.Append(mesh, geo.Layout);
// Important: This transform should only be applied once, since the pools are shared, and
// cannot include any mesh-local transformations.
ExportUtils.ConvertToMetersAndChangeBasis(geo, ExportUtils.GetBasisMatrix(payload));
if (reverseWinding)
{
// Note: this triangle flip intentionally un-does the Unity FBX import flip.
ExportUtils.ReverseTriangleWinding(geo, 1, 2);
}
var objectMesh = new ModelMesh {
model = null, // The model is only used for uniquefying the texture names.
name = exportName + "_" + i + "_" + sm,
id = data.renderer.gameObject.GetInstanceID(),
pool = geo,
xform = ExportUtils.ChangeBasisNonUniformScale(payload, data.renderer.localToWorldMatrix),
exportableMaterial = exportableMaterial,
meshIndex = i
};
yield return(objectMesh);
}
}
}
