TonyPa, Ed Mack, Vengeance, anyone!?

[Scotopia]

Hey guys.. I have a problem thats driving me nuts, and I am hoping one of you can propose a modification or a better way. I am making a tilebased breakout engine (using ideas from tonypas tutorial) and I am up to the part that checks for collisions, richochets the ball, and deletes brick. My code seems to work but if the ball happens to hit a certain spot (maybe right in between too bricks) it will kind of zig zag through them and annhilate way more than it should. Perhaps this is because I am using the basic hitTest which involves the bounding box of the ball, and maybe the problem would resolve itself if I used the other type of hittest (which i am not quite sure how too). Another idea i thought of was maybe having like a very very small weight timer, that only lets a brick be destroyed if some increment of time has gone by since the last destruction (i dont like this idea though, could cause problems) My code for the hittest part is below. If you guys have any suggested modifications or alternate methods of approach I would reaaaallly appreciate it. Thank you very much in advance.

---Keith

code:

---

	function getMyCorners(x, y, ob) {

	// find corner points

	ob.upY = Math.floor((y+ob.height-1)/game.tileH);

	ob.downY = Math.floor((y-ob.height)/game.tileH);

	ob.rightX = Math.floor((x-ob.width)/game.tileW);

	ob.leftX = Math.floor((x+ob.width-1)/game.tileW);

	// check if they are walls

	ob.downright = game["t_"+ob.downY+"_"+ob.rightX].walkable;

	ob.upright = game["t_"+ob.upY+"_"+ob.rightX].walkable;

	ob.downleft = game["t_"+ob.downY+"_"+ob.leftX].walkable;

	ob.upleft = game["t_"+ob.upY+"_"+ob.leftX].walkable;

	}

	

	function moveBall(ob) {		

		

		//check horizontal collisions first 

		getMyCorners (ob._x + ob.xspeed, ob._y, ob);

		

		if ( !(ob.downright && ob.upright && ob.downleft && ob.upleft))

		{

			if (game.clip["t_"+ob.downY+"_"+ob.rightX].hitTest(ball)) {

				

				ball.xspeed *= -1; 

				removeMovieClip(game.clip["t_"+ob.downY+"_"+ob.rightX]);

			}

			

			if (game.clip["t_"+ob.upY+"_"+ob.rightX].hitTest(ball)) {

				

				ball.xspeed *= -1;

				removeMovieClip(game.clip["t_"+ob.upY+"_"+ob.rightX]);

			}

			

			if (game.clip["t_"+ob.downY+"_"+ob.leftX].hitTest(ball)) {

				

				ball.xspeed *= -1;

				removeMovieClip(game.clip["t_"+ob.downY+"_"+ob.leftX]);

			}

			

			if (game.clip["t_"+ob.upY+"_"+ob.leftX].hitTest(ball)) {

				

				ball.xspeed *= -1;

				removeMovieClip(game.clip["t_"+ob.upY+"_"+ob.leftX]);

			}

			

		

		}

		

		//check vertical collisions

		getMyCorners (ob._x, ob._y + ob.yspeed, ob);

		

		if ( !(ob.downright && ob.upright && ob.downleft && ob.upleft))

		{

			if (game.clip["t_"+ob.downY+"_"+ob.rightX].hitTest(ball)) {

				

				ball.yspeed *= -1; 

				removeMovieClip(game.clip["t_"+ob.downY+"_"+ob.rightX]);

			}

			

			if (game.clip["t_"+ob.upY+"_"+ob.rightX].hitTest(ball)) {

				

				ball.yspeed *= -1;

				removeMovieClip(game.clip["t_"+ob.upY+"_"+ob.rightX]);

			}

			

			if (game.clip["t_"+ob.downY+"_"+ob.leftX].hitTest(ball)) {

				

				ball.yspeed *= -1;

				removeMovieClip(game.clip["t_"+ob.downY+"_"+ob.leftX]);

			}

			

			if (game.clip["t_"+ob.upY+"_"+ob.leftX].hitTest(ball)) {

				

				ball.yspeed *= -1;

				removeMovieClip(game.clip["t_"+ob.upY+"_"+ob.leftX]);

			}

			

		

		}

		

			

		ball._x += ball.xspeed; //move depending on our xspeed

		ball._y += ball.yspeed; //move depending on our yspeed

---

P.S. I know i could clean this up a bit by making better use of functions... but I'll save that till I actually have it right....

[tonypa]

I am pretty sure you should use if...else statements so only 1 block is destroyed at each step.

[Scotopia]

usually only one block does get destroyed, unless it happens to hit in a certain way, then it does what i said. Also, if you do if/else, wouldn't you be giving precedence to one kind of collision over the other?

[Scotopia]

What say you, tonypa? (or anyone else)

[kyled]

use ifs to detect the problem, even use double ifs, If the ball hits in that area and will create that bug the do this, ie, if this block is hit and this block is there do this action that will lead it away from your bug.