Pathfinding

[willy]

I found this article on how to make a path finding formula: http://www.clickteam.info/kb/start/i...?showtopic=313

However, the example doesn’t work, and I’m not sure how to make one myself.

Angle = Angle + CollisionMask( X + Cos( Angle - 45) * 64, Y + Sin( Angle - 45) * 64 ) * 3
Angle = Angle - CollisionMask( X + Cos( Angle + 45) * 64, Y + Sin( Angle + 45 ) * 64 ) * 3

I have no idea how to use this code. Can anyone explain or preferably make an example showing how to make a pathfinding code based on this formula using 32 directions instead of 360?

[LazyCoder]

This is really for people who are making a 'custom' movement by using event lines.

What you should do instead since you are using 32 directions is use this event:
--Always
-Set direction to direction + CollisionMask(X + Cos(direction*11.25 - 45) * 64,X + Cos(direction*11.25 - 45) * 64)
-Set direction to direction - CollisionMask(X + Cos(direction*11.25 + 45) * 64,X + Cos(direction*11.25 + 45) * 64)

[willy]

Sorry, I get an error. I’m really bad at this formula thing. How is it done, exactly? If lets say, the “enemy” has to find the “player”, shouldn’t that be in the formula? I tried editing the thing, but with no luck.

[willy]

I've uploaded a file that uses collision mask. Can someone tell me why it doesn't work?
http://mb.erathean.com/collisionmask.mfa

It is supposed to move on a parallel line with the obstacles

[DanielRehn]

Use theese instead

Dir( "Enemy" )-CollisionMask(X( "Enemy" )+Cos((Dir( "Enemy" )*-11.25)-45)*16, Y( "Enemy" )+Sin((Dir( "Enemy" )*-11.25)-45)*16)

Dir( "Enemy" )+CollisionMask(X( "Enemy" )+Cos((Dir( "Enemy" )*-11.25)+45)*16, Y( "Enemy" )+Sin((Dir( "Enemy" )*-11.25)+45)*16)

Directions work the opposite way from angles in MMF

[LazyCoder]

Ah. I see.

[willy]

Thanks guys, but it didn’t turn out as I had hoped. It still doesn’t find it’s path.

[DanielRehn]

Of course it does'nt... this only tells it to turn if it gets close to a wall...

[Bernie]

There is a pathfinding extension available for MMF2. It works very well, definitely worth a try.

[willy]

Yeah, but it’s so hard to use.

But that collision mask thing would be very handy to fix the bug where enemies get stuck inside walls. Could you Daniel, or someone else, help me tune the code a little. It is a little buggy, it seems it needs just some fine tuning. Because when I use this code:

Dir( "Enemy" )-CollisionMask(X( "Enemy" )+Cos((Dir( "Enemy" )*-11.25)-45)*16, Y( "Enemy" )+Sin((Dir( "Enemy" )*-11.25)-45)*16)
Dir( "Enemy" )+CollisionMask(X( "Enemy" )+Cos((Dir( "Enemy" )*-11.25)+45)*16, Y( "Enemy" )+Sin((Dir( "Enemy" )*-11.25)+45)*16)

The Enemy turns away from the wall a little to late when walking towards the down and right wall. I’m sure all I need to do is to change some of those numbers to make it walk away a little sooner, but I can’t find the right once.