Function expire_gas_cloud

src/region.c:1045–1087

* Here is an example of an expire function that may prolong * region life after some mods... */ ARGSUSED*/

 */
/*ARGSUSED*/
boolean
expire_gas_cloud(genericptr_t p1, genericptr_t p2 UNUSED)
{
    NhRegion *reg;
    int damage, pass;
    coordxy x, y;

    reg = (NhRegion *) p1;
    damage = reg->arg.a_int;

    /* If it was a thick cloud, it dissipates a little first */
    if (damage >= 5) {
        damage /= 2; /* It dissipates, let's do less damage */
        reg->arg = cg.zeroany;
        reg->arg.a_int = damage;
        reg->ttl = 2L; /* Here's the trick : reset ttl */
        return FALSE;  /* THEN return FALSE, means "still there" */
    }

    /* The cloud no longer blocks vision.  cansee() checks shouldn't be made
       until all blocked spots have been unblocked, so we need two passes */
    for (pass = 1; pass <= (Blind ? 1 : 2); ++pass) {
        for (x = reg->bounding_box.lx; x <= reg->bounding_box.hx; x++) {
            for (y = reg->bounding_box.ly; y <= reg->bounding_box.hy; y++) {
                if (inside_region(reg, x, y)) {
                    if (pass == 1) {
                        if (!does_block(x, y, &levl[x][y]))
                            unblock_point(x, y);
                    } else { /* pass==2 */
                        if (!u.uswallow) {
                            if (u_at(x, y))
                                gg.gas_cloud_diss_within = TRUE;
                            else if (cansee(x, y))
                                gg.gas_cloud_diss_seen++;
                        }
                    }
                }
            }
        }
    }

    return TRUE; /* OK, it's gone, you can free it! */
}

/* returns True if p2 is killed by region p1, False otherwise */
boolean