;; use nvgArcTo (bind-func xtm_add_arc (lambda (path x1:i64 y1:i64 x2:i64 y2:i64 x3:i64 y3:i64 rad:i64) (nvgMoveTo path (i64tof x1) (i64tof y1)) (nvgArcTo path (i64tof x2) (i64tof y2) (i64tof x3) (i64tof y3) (i64tof rad))))