btmagic_scale
dx = btmagic_scale(dx, &sc->sc_rx, sc->sc_resolution);
dy = btmagic_scale(dy, &sc->sc_ry, sc->sc_resolution);
dx = btmagic_scale(dx, &sc->sc_rx, sc->sc_resolution);
dy = btmagic_scale(dy, &sc->sc_ry, sc->sc_resolution);
dz += btmagic_scale(tz, &sc->sc_rz,
dw += btmagic_scale(tw, &sc->sc_rw,
dx += btmagic_scale(tx, &sc->sc_rx,
dy += btmagic_scale(ty, &sc->sc_ry,
dz += btmagic_scale(ty, &sc->sc_rz,
dw += btmagic_scale(tx, &sc->sc_rw,
static int btmagic_scale(int, int *, int);