shots.c

早期freebsd实现

		  case 1:
			MINUS_DELTA(x, 1);
			break;
		  case 2:
			PLUS_DELTA(y, HEIGHT - 2);
			break;
		  case 3:
			MINUS_DELTA(y, 1);
			break;
		}
		goto again;
	  case WALL1:
	  case WALL2:
	  case WALL3:
# ifdef	REFLECT
	  case WALL4:
	  case WALL5:
# endif
# ifdef	RANDOM
	  case DOOR:
# endif
		if (pp->p_flying == 0)
			pp->p_flying++;
		break;
	  case SPACE:
		break;
	}
	pp->p_y = y;
	pp->p_x = x;
	if (pp->p_flying-- == 0) {
# ifdef BOOTS
		if (pp->p_face != BOOT && pp->p_face != BOOT_PAIR) {
# endif
			checkdam(pp, (PLAYER *) NULL, (IDENT *) NULL,
				rand_num(pp->p_damage / 5), FALL);
			pp->p_face = rand_dir();
			showstat(pp);
# ifdef BOOTS
		}
		else {
			if (Maze[y][x] == BOOT)
				pp->p_face = BOOT_PAIR;
			Maze[y][x] = SPACE;
		}
# endif
	}
	pp->p_over = Maze[y][x];
	Maze[y][x] = pp->p_face;
	showexpl(y, x, pp->p_face);
}

/*
 * chkshot
 *	Handle explosions
 */
chkshot(bp, next)
register BULLET	*bp;
BULLET		*next;
{
	register int	y, x;
	register int	dy, dx, absdy;
	register int	delta, damage;
	register char	expl;
	register PLAYER	*pp;

	switch (bp->b_type) {
	  case SHOT:
	  case MINE:
	  case GRENADE:
	  case GMINE:
	  case SATCHEL:
	  case BOMB:
		delta = bp->b_size - 1;
		break;
# ifdef	OOZE
	  case SLIME:
# ifdef VOLCANO
	  case LAVA:
# endif
		chkslime(bp, next);
		return;
# endif
# ifdef DRONE
	  case DSHOT:
		bp->b_type = SLIME;
		chkslime(bp, next);
		return;
# endif
	}
	for (y = bp->b_y - delta; y <= bp->b_y + delta; y++) {
		if (y < 0 || y >= HEIGHT)
			continue;
		dy = y - bp->b_y;
		absdy = (dy < 0) ? -dy : dy;
		for (x = bp->b_x - delta; x <= bp->b_x + delta; x++) {
			if (x < 0 || x >= WIDTH)
				continue;
			dx = x - bp->b_x;
			if (dx == 0)
				expl = (dy == 0) ? '*' : '|';
			else if (dy == 0)
				expl = '-';
			else if (dx == dy)
				expl = '\\';
			else if (dx == -dy)
				expl = '/';
			else
				expl = '*';
			showexpl(y, x, expl);
			switch (Maze[y][x]) {
			  case LEFTS:
			  case RIGHT:
			  case ABOVE:
			  case BELOW:
# ifdef FLY
			  case FLYER:
# endif
				if (dx < 0)
					dx = -dx;
				if (absdy > dx)
					damage = bp->b_size - absdy;
				else
					damage = bp->b_size - dx;
				pp = play_at(y, x);
				checkdam(pp, bp->b_owner, bp->b_score,
					damage * MINDAM, bp->b_type);
				break;
			  case GMINE:
			  case MINE:
				add_shot((Maze[y][x] == GMINE) ?
					GRENADE : SHOT,
					y, x, LEFTS,
					(Maze[y][x] == GMINE) ?
					GRENREQ : BULREQ,
					(PLAYER *) NULL, TRUE, SPACE);
				Maze[y][x] = SPACE;
				break;
			}
		}
	}
}

# ifdef	OOZE
/*
 * chkslime:
 *	handle slime shot exploding
 */
chkslime(bp, next)
register BULLET	*bp;
BULLET		*next;
{
	register BULLET	*nbp;

	switch (Maze[bp->b_y][bp->b_x]) {
	  case WALL1:
	  case WALL2:
	  case WALL3:
# ifdef	REFLECT
	  case WALL4:
	  case WALL5:
# endif
# ifdef	RANDOM
	  case DOOR:
# endif
		switch (bp->b_face) {
		  case LEFTS:
			bp->b_x++;
			break;
		  case RIGHT:
			bp->b_x--;
			break;
		  case ABOVE:
			bp->b_y++;
			break;
		  case BELOW:
			bp->b_y--;
			break;
		}
		break;
	}
	nbp = (BULLET *) malloc(sizeof (BULLET));
	*nbp = *bp;
# ifdef VOLCANO
	move_slime(nbp, nbp->b_type == SLIME ? SLIMESPEED : LAVASPEED, next);
# else
	move_slime(nbp, SLIMESPEED, next);
# endif
}

/*
 * move_slime:
 *	move the given slime shot speed times and add it back if
 *	it hasn't fizzled yet
 */
move_slime(bp, speed, next)
register BULLET	*bp;
register int	speed;
BULLET		*next;
{
	register int	i, j, dirmask, count;
	register PLAYER	*pp;
	register BULLET	*nbp;

	if (speed == 0) {
		if (bp->b_charge <= 0)
			free((char *) bp);
		else
			save_bullet(bp);
		return;
	}

# ifdef VOLCANO
	showexpl(bp->b_y, bp->b_x, bp->b_type == LAVA ? LAVA : '*');
# else
	showexpl(bp->b_y, bp->b_x, '*');
# endif
	switch (Maze[bp->b_y][bp->b_x]) {
	  case LEFTS:
	  case RIGHT:
	  case ABOVE:
	  case BELOW:
# ifdef FLY
	  case FLYER:
# endif
		pp = play_at(bp->b_y, bp->b_x);
		message(pp, "You've been slimed.");
		checkdam(pp, bp->b_owner, bp->b_score, MINDAM, bp->b_type);
		break;
	  case SHOT:
	  case GRENADE:
	  case SATCHEL:
	  case BOMB:
# ifdef DRONE
	  case DSHOT:
# endif
		explshot(next, bp->b_y, bp->b_x);
		explshot(Bullets, bp->b_y, bp->b_x);
		break;
	}

	if (--bp->b_charge <= 0) {
		free((char *) bp);
		return;
	}

	dirmask = 0;
	count = 0;
	switch (bp->b_face) {
	  case LEFTS:
		if (!iswall(bp->b_y, bp->b_x - 1))
			dirmask |= WEST, count++;
		if (!iswall(bp->b_y - 1, bp->b_x))
			dirmask |= NORTH, count++;
		if (!iswall(bp->b_y + 1, bp->b_x))
			dirmask |= SOUTH, count++;
		if (dirmask == 0)
			if (!iswall(bp->b_y, bp->b_x + 1))
				dirmask |= EAST, count++;
		break;
	  case RIGHT:
		if (!iswall(bp->b_y, bp->b_x + 1))
			dirmask |= EAST, count++;
		if (!iswall(bp->b_y - 1, bp->b_x))
			dirmask |= NORTH, count++;
		if (!iswall(bp->b_y + 1, bp->b_x))
			dirmask |= SOUTH, count++;
		if (dirmask == 0)
			if (!iswall(bp->b_y, bp->b_x - 1))
				dirmask |= WEST, count++;
		break;
	  case ABOVE:
		if (!iswall(bp->b_y - 1, bp->b_x))
			dirmask |= NORTH, count++;
		if (!iswall(bp->b_y, bp->b_x - 1))
			dirmask |= WEST, count++;
		if (!iswall(bp->b_y, bp->b_x + 1))
			dirmask |= EAST, count++;
		if (dirmask == 0)
			if (!iswall(bp->b_y + 1, bp->b_x))
				dirmask |= SOUTH, count++;
		break;
	  case BELOW:
		if (!iswall(bp->b_y + 1, bp->b_x))
			dirmask |= SOUTH, count++;
		if (!iswall(bp->b_y, bp->b_x - 1))
			dirmask |= WEST, count++;
		if (!iswall(bp->b_y, bp->b_x + 1))
			dirmask |= EAST, count++;
		if (dirmask == 0)
			if (!iswall(bp->b_y - 1, bp->b_x))
				dirmask |= NORTH, count++;
		break;
	}
	if (count == 0) {
		/*
		 * No place to go.  Just sit here for a while and wait
		 * for adjacent squares to clear out.
		 */
		save_bullet(bp);
		return;
	}
	if (bp->b_charge < count) {
		/* Only bp->b_charge paths may be taken */
		while (count > bp->b_charge) {
			if (dirmask & WEST)
				dirmask &= ~WEST;
			else if (dirmask & EAST)
				dirmask &= ~EAST;
			else if (dirmask & NORTH)
				dirmask &= ~NORTH;
			else if (dirmask & SOUTH)
				dirmask &= ~SOUTH;
			count--;
		}
	}

	i = bp->b_charge / count;
	j = bp->b_charge % count;
	if (dirmask & WEST) {
		count--;
		nbp = create_shot(bp->b_type, bp->b_y, bp->b_x - 1, LEFTS,
			i, bp->b_size, bp->b_owner, bp->b_score, TRUE, SPACE);
		move_slime(nbp, speed - 1, next);
	}
	if (dirmask & EAST) {
		count--;
		nbp = create_shot(bp->b_type, bp->b_y, bp->b_x + 1, RIGHT,
			(count < j) ? i + 1 : i, bp->b_size, bp->b_owner,
			bp->b_score, TRUE, SPACE);
		move_slime(nbp, speed - 1, next);
	}
	if (dirmask & NORTH) {
		count--;
		nbp = create_shot(bp->b_type, bp->b_y - 1, bp->b_x, ABOVE,
			(count < j) ? i + 1 : i, bp->b_size, bp->b_owner,
			bp->b_score, TRUE, SPACE);
		move_slime(nbp, speed - 1, next);
	}
	if (dirmask & SOUTH) {
		count--;
		nbp = create_shot(bp->b_type, bp->b_y + 1, bp->b_x, BELOW,
			(count < j) ? i + 1 : i, bp->b_size, bp->b_owner,
			bp->b_score, TRUE, SPACE);
		move_slime(nbp, speed - 1, next);
	}

	free((char *) bp);
}

/*
 * iswall:
 *	returns whether the given location is a wall
 */
iswall(y, x)
register int	y, x;
{
	if (y < 0 || x < 0 || y >= HEIGHT || x >= WIDTH)
		return TRUE;
	switch (Maze[y][x]) {
	  case WALL1:
	  case WALL2:
	  case WALL3:
# ifdef	REFLECT
	  case WALL4:
	  case WALL5:
# endif
# ifdef	RANDOM
	  case DOOR:
# endif
# ifdef OOZE
	  case SLIME:
# ifdef VOLCANO
	  case LAVA:
# endif
# endif
		return TRUE;
	}
	return FALSE;
}
# endif

/*
 * zapshot:
 *	Take a shot out of the air.
 */
zapshot(blist, obp)
register BULLET	*blist, *obp;
{
	register BULLET	*bp;
	register FLAG	explode;

	explode = FALSE;
	for (bp = blist; bp != NULL; bp = bp->b_next) {
		if (bp->b_x != obp->b_x || bp->b_y != obp->b_y)
			continue;
		if (bp->b_face == obp->b_face)
			continue;
		explode = TRUE;
		break;
	}
	if (!explode)
		return;
	explshot(blist, obp->b_y, obp->b_x);
}

/*
 * explshot -
 *	Make all shots at this location blow up
 */
explshot(blist, y, x)
register BULLET	*blist;
register int	y, x;
{
	register BULLET	*bp;

	for (bp = blist; bp != NULL; bp = bp->b_next)
		if (bp->b_x == x && bp->b_y == y) {
			bp->b_expl = TRUE;
			if (bp->b_owner != NULL)
				message(bp->b_owner, "Shot intercepted");
		}
}

/*
 * play_at:
 *	Return a pointer to the player at the given location
 */
PLAYER *
play_at(y, x)
register int	y, x;
{
	register PLAYER	*pp;

	for (pp = Player; pp < End_player; pp++)
		if (pp->p_x == x && pp->p_y == y)
			return pp;
	fprintf(stderr, "driver: couldn't find player at (%d,%d)\n", x, y);
	abort();
	/* NOTREACHED */
}

/*
 * opposite:
 *	Return TRUE if the bullet direction faces the opposite direction
 *	of the player in the maze
 */
opposite(face, dir)
int	face;
char	dir;
{
	switch (face) {
	  case LEFTS:
		return (dir == RIGHT);
	  case RIGHT:
		return (dir == LEFTS);
	  case ABOVE:
		return (dir == BELOW);
	  case BELOW:
		return (dir == ABOVE);
	  default:
		return FALSE;
	}
}

/*
 * is_bullet:
 *	Is there a bullet at the given coordinates?  If so, return
 *	a pointer to the bullet, otherwise return NULL
 */
BULLET *
is_bullet(y, x)
register int	y, x;
{
	register BULLET	*bp;

	for (bp = Bullets; bp != NULL; bp = bp->b_next)
		if (bp->b_y == y && bp->b_x == x)
			return bp;
	return NULL;
}

/*
 * fixshots:
 *	change the underlying character of the shots at a location
 *	to the given character.
 */
fixshots(y, x, over)
register int	y, x;
char		over;
{
	register BULLET	*bp;

	for (bp = Bullets; bp != NULL; bp = bp->b_next)
		if (bp->b_y == y && bp->b_x == x)
			bp->b_over = over;
}

/*
 * find_under:
 *	find the underlying character for a bullet when it lands
 *	on another bullet.
 */
find_under(blist, bp)
register BULLET	*blist, *bp;
{
	register BULLET	*nbp;

	for (nbp = blist; nbp != NULL; nbp = nbp->b_next)
		if (bp->b_y == nbp->b_y && bp->b_x == nbp->b_x) {
			bp->b_over = nbp->b_over;
			break;
		}
}

/*
 * mark_player:
 *	mark a player as under a shot
 */
mark_player(bp)
register BULLET	*bp;
{
	register PLAYER	*pp;

	for (pp = Player; pp < End_player; pp++)
		if (pp->p_y == bp->b_y && pp->p_x == bp->b_x) {
			pp->p_undershot = TRUE;
			break;
		}
}

# ifdef BOOTS
/*
 * mark_boot:
 *	mark a boot as under a shot
 */
mark_boot(bp)
register BULLET	*bp;
{
	register PLAYER	*pp;

	for (pp = Boot; pp < &Boot[NBOOTS]; pp++)
		if (pp->p_y == bp->b_y && pp->p_x == bp->b_x) {
			pp->p_undershot = TRUE;
			break;
		}
}
# endif