Function launch_obj

src/trap.c:3259–3575

* Move obj from (x1,y1) to (x2,y2) * * Return 0 if no object was launched. * 1 if an object was launched and placed somewhere. * 2 if an object was launched, but used up. */

 *        2 if an object was launched, but used up.
 */
int
launch_obj(
    short otyp,
    coordxy x1, coordxy y1,
    coordxy x2, coordxy y2,
    int style)
{
    struct monst *mtmp;
    struct obj *otmp, *otmp2;
    int dx, dy;
    coordxy x, y;
    struct obj *singleobj;
    boolean used_up = FALSE, otherside = FALSE;
    int dist, tmp, delaycnt = 0;

    otmp = sobj_at(otyp, x1, y1);
    /* Try the other side too, for rolling boulder traps */
    if (!otmp && otyp == BOULDER) {
        otherside = TRUE;
        otmp = sobj_at(otyp, x2, y2);
    }
    if (!otmp)
        return 0;
    if (otherside) { /* swap 'em */
        int tx, ty;

        tx = x1;
        ty = y1;
        x1 = x2;
        y1 = y2;
        x2 = tx;
        y2 = ty;
    }

    if (otmp->quan == 1L) {
        obj_extract_self(otmp);
        maybe_unhide_at(otmp->ox, otmp->oy);
        singleobj = otmp;
        otmp = (struct obj *) 0;
    } else {
        singleobj = splitobj(otmp, 1L);
        obj_extract_self(singleobj);
    }
    newsym(x1, y1);
    /* in case you're using a pick-axe to chop the boulder that's being
       launched (perhaps a monster triggered it), destroy context so that
       the next dig attempt never thinks that you're resuming
       the previous effort */
    if ((otyp == BOULDER || otyp == STATUE)
        && singleobj->ox == svc.context.digging.pos.x
        && singleobj->oy == svc.context.digging.pos.y)
        (void) memset((genericptr_t) &svc.context.digging, 0,
                      sizeof(struct dig_info));

    dist = distmin(x1, y1, x2, y2);
    x = gb.bhitpos.x = x1;
    y = gb.bhitpos.y = y1;
    dx = sgn(x2 - x1);