Thank you. I have figured out what scale_s and scale_t mean by trying several special textures. However, I also found that scale_s and scale_t can only be used when to calculate UVs on group objects and component objects. So, if one face is attached with group material, we should multiply the stq coordinates returned by SUMeshHelperGetSTQCoords or SUUVHelperGetUVQ by s&t scale to get the right UVs while we shouldn’t if the face is attached with its own material returned by SUFaceGet*Material. Do I mistake anything?