Bowling Bash Stun on Hitting Against Wall

[Vyserion]

Hello guys!

  How can I do to make Bowling Bash stun the target with a chance, when being knocked back against a wall?

case KN_BOWLINGBASH:
	case MS_BOWLINGBASH:
		{
			int min_x,max_x,min_y,max_y,i,c,dir,tx,ty;
			// Chain effect and check range gets reduction by recursive depth, as this can reach 0, we don't use blowcount
			c = (skill_lv-(flag&0xFFF)+1)/2;
			// Determine the Bowling Bash area depending on configuration
			if (battle_config.bowling_bash_area == 0) {
				// Gutter line system
				min_x = ((src->x)-c) - ((src->x)-c)%40;
				if(min_x < 0) min_x = 0;
				max_x = min_x + 39;
				min_y = ((src->y)-c) - ((src->y)-c)%40;
				if(min_y < 0) min_y = 0;
				max_y = min_y + 39;
			} else if (battle_config.bowling_bash_area == 1) {
				// Gutter line system without demi gutter bug
				min_x = src->x - (src->x)%40;
				max_x = min_x + 39;
				min_y = src->y - (src->y)%40;
				max_y = min_y + 39;
			} else {
				// Area around caster
				min_x = src->x - battle_config.bowling_bash_area;
				max_x = src->x + battle_config.bowling_bash_area;
				min_y = src->y - battle_config.bowling_bash_area;
				max_y = src->y + battle_config.bowling_bash_area;
			}
			// Initialization, break checks, direction
			if((flag&0xFFF) > 0) {
				// Ignore monsters outside area
				if(bl->x < min_x || bl->x > max_x || bl->y < min_y || bl->y > max_y)
					break;
				// Ignore monsters already in list
				if(idb_exists(bowling_db, bl->id))
					break;
				// Random direction
				dir = rnd()%8;
			} else {
				// Create an empty list of already hit targets
				db_clear(bowling_db);
				// Direction is walkpath
				dir = (unit_getdir(src)+4)%8;
			}
			// Add current target to the list of already hit targets
			idb_put(bowling_db, bl->id, bl);
			// Keep moving target in direction square by square
			tx = bl->x;
			ty = bl->y;
			for(i=0;i<c;i++) {
				// Target coordinates (get changed even if knockback fails)
				tx -= dirx[dir];
				ty -= diry[dir];
				// If target cell is a wall then break
				if(map_getcell(bl->m,tx,ty,CELL_CHKWALL))
					break;
				skill_blown(src,bl,1,dir,BLOWN_NONE);

				int count;

				// Splash around target cell, but only cells inside area; we first have to check the area is not negative
				if((max(min_x,tx-1) <= min(max_x,tx+1)) &&
					(max(min_y,ty-1) <= min(max_y,ty+1)) &&
					(count = map_foreachinallarea(skill_area_sub, bl->m, max(min_x,tx-1), max(min_y,ty-1), min(max_x,tx+1), min(max_y,ty+1), splash_target(src), src, skill_id, skill_lv, tick, flag|BCT_ENEMY, skill_area_sub_count))) {
					// Recursive call
					map_foreachinallarea(skill_area_sub, bl->m, max(min_x,tx-1), max(min_y,ty-1), min(max_x,tx+1), min(max_y,ty+1), splash_target(src), src, skill_id, skill_lv, tick, (flag|BCT_ENEMY)+1, skill_castend_damage_id);
					// Self-collision
					if(bl->x >= min_x && bl->x <= max_x && bl->y >= min_y && bl->y <= max_y)
						skill_attack(BF_WEAPON,src,src,bl,skill_id,skill_lv,tick,(flag&0xFFF)>0?SD_ANIMATION|count:count);
					break;
				}
			}
#ifndef  RENEWAL
			// Original hit or chain hit depending on flag
			skill_attack(BF_WEAPON,src,src,bl,skill_id,skill_lv,tick,(flag&0xFFF)>0?SD_ANIMATION:0);
#endif
		}
		break;