Flint Particle System Forum - bounding box: other shapes than just a box?

bounding box: other shapes than just a box?

kirbysayshi — Sun, 05 Apr 2009 20:46:23 +0100

Is it possible to create an irregularly-shaped bounding box?
Something like:


 _________
|         |
|         |
|    T    |
|         |
|__     __|
   |   |
   |   |
   |   |
   |   |
   |   |
   |   |
   |   |
   | E |

Where T is where the particles are moving towards, E is the emitter, and the inner area is a the bounding box. Right now, my shapes are being generated based on tiles, with the idea that a horde of zombies (the particles) are chasing after you in a slow, yet powerful mass, bouncing off of the walls of the environment and blockades you erect.

I tried adding in a second bounding box that overlapped the first, but flint didn't seem to like that.

I saw the way the Flint logo demo accepted a BitmapData object... it would be very cool if something like that could be done to define a bounding area based on a specific color.

Any ideas?

bounding box: other shapes than just a box?

kirbysayshi — Mon, 06 Apr 2009 22:20:53 +0100

I read this thread:
http://flintparticles.org/forum/comments.php?DiscussionID=142

And it sounds like we're trying to do the same thing. Is there an action that can be added to a zone that will provide "bounce" or something like that? Could you use an acceleration action, in combination with a ZonedAction to provide irregular bounding boxes? I'll try this later, after class (I'm just throwing it out there for the sake of idea).

bounding box: other shapes than just a box?

Richard — Mon, 06 Apr 2009 23:15:49 +0100

There's a branch in svn called linesandcollisions in which I've started implementing this. I'm aiming to complete this for release later - probably version 2.2.

I was planning it for 2.1 but am rushed off my feet with work so 2.1 will probably just be the 3dgeom and flex branches, which are much closer to completion, with linesandcollisions in 2.2.

bounding box: other shapes than just a box?

kirbysayshi — Tue, 07 Apr 2009 05:00:36 +0100

Ok cool. I eagerly await the release!

I've been experimenting with using multiple AntiGravity actions as walls. Do you have any suggestions? I can't quite get the numbers right... the particles still slip by. My tiles are 16x16, and I'm putting the AntiGravity wells in the center of each wall tile. I'm hoping there might be a way to set up "absolute reverse gravity" at a set distance by fiddling with the numbers...

I can test for collisions with things by looping through the children of the renderer, but this doesn't seem very efficient.

bounding box: other shapes than just a box?

Richard — Tue, 07 Apr 2009 07:58:37 +0100

My best suggestion would be to look at what I've done so far in the linesandcollisions branch and take it from there.

bounding box: other shapes than just a box?

kirbysayshi — Tue, 07 Apr 2009 18:38:45 +0100

Ok, will do.

A related/unrelated question: is it possible, without making a new action, to have the particles added to a secondary array/list as they are created?

bounding box: other shapes than just a box?

Richard — Thu, 09 Apr 2009 07:36:11 +0100

No, but it's an initializer that you need, not an action.