Java-Gaming.org Hi !
 Featured games (90) games approved by the League of Dukes Games in Showcase (780) Games in Android Showcase (233) games submitted by our members Games in WIP (857) games currently in development
 News: Read the Java Gaming Resources, or peek at the official Java tutorials
 Home Help Search Login Register
Pages: [1]
 ignore  |  Print
 fast algorithms  (Read 1527 times) 0 Members and 1 Guest are viewing this topic.
PRW56

Senior Newbie

 « Posted 2012-09-10 06:36:26 »

Ok I have a situation where one character must test whether they collide with any other characters or debris, so far I have done this by testing whether or not the characters rectangle intersects another character or debris' rectangle. As you can imagine this will become very big as more characters are added into a game, so I wonder if there is an algorithm that would handle this more effectively? Any kind of link to a site or book that has other algorithms useful to game development would be nice as well.

Ty for any and all help.
HeroesGraveDev

JGO Kernel

Medals: 382
Projects: 11
Exp: 4 years

┬─┬ノ(ಠ_ಠノ)(╯°□°)╯︵ ┻━┻

 « Reply #1 - Posted 2012-09-10 06:49:01 »

What you need, is to cut down on the collisions being checked.

Here are some choices that I recommend:

• Circle Collisions

Google Quadtrees, as they are quite abstract.

For circle collisions, change to using circles instead of AABBs.
Then do this:

 1  2  3  4  5  6  7 `float dx = this.x - other.x;float dy = this.y - other.y;float r = this.radiusSquared + other.radiusSquared;if((dx*dx)+(dy*dy) < r){// the objects collided. do whatever.}`

The variables should be self-explanatory

Also, just think about different ways of cutting down on the amount of checks.
Test those methods with large amounts of objects.
Compare FPS.
Implement if successful.

Hopefully you can get this to work

philfrei
 « Reply #2 - Posted 2012-09-10 07:41:15 »

There are several active threads here on this very subject.

This thread has the additional benefit of linking to several others:
http://www.java-gaming.org/topics/random-thoughts-extreme-speed-2d-collisions/27331/view.html

music and music apps: http://adonax.com
Pages: [1]
 ignore  |  Print

 hadezbladez (734 views) 2018-11-16 13:46:03 hadezbladez (372 views) 2018-11-16 13:41:33 hadezbladez (724 views) 2018-11-16 13:35:35 hadezbladez (186 views) 2018-11-16 13:32:03 EgonOlsen (2384 views) 2018-06-10 19:43:48 EgonOlsen (2537 views) 2018-06-10 19:43:44 EgonOlsen (1472 views) 2018-06-10 19:43:20 DesertCoockie (2136 views) 2018-05-13 18:23:11 nelsongames (1933 views) 2018-04-24 18:15:36 nelsongames (2614 views) 2018-04-24 18:14:32
 Deployment and Packagingby mudlee2018-08-22 18:09:50Java Gaming Resourcesby gouessej2018-08-22 08:19:41Deployment and Packagingby gouessej2018-08-22 08:04:08Deployment and Packagingby gouessej2018-08-22 08:03:45Deployment and Packagingby philfrei2018-08-20 02:33:38Deployment and Packagingby philfrei2018-08-20 02:29:55Deployment and Packagingby philfrei2018-08-19 23:56:20Deployment and Packagingby philfrei2018-08-19 23:54:46
 java-gaming.org is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑gaming.org