*vbuf->vertex_ptr++ = pack_ub4(float_to_ubyte( vertex->data[j][2] ),
float_to_ubyte( vertex->data[j][1] ),
float_to_ubyte( vertex->data[j][0] ),
*vbuf->vertex_ptr++ = pack_ub4(float_to_ubyte( vertex->data[j][2] ),
float_to_ubyte( vertex->data[j][1] ),
float_to_ubyte( vertex->data[j][0] ),