Hi !
Featured games (91)
games approved by the League of Dukes
Games in Showcase (757)
Games in Android Showcase (229)
games submitted by our members
Games in WIP (844)
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  
  hmmm... efficient collision?  (Read 2883 times)
0 Members and 1 Guest are viewing this topic.
Offline NexusOne

Junior Devvie

Java games rock!

« Posted 2004-01-03 23:24:45 »

I'm thinking of a way to create efficient collision detection in a 3d world. Would it be efficient enough if I were to create a 2d array of linked lists of references to game objects, where the each slot in the array is imagined to be a column in the 3d world, of objects with similar x and z coordinates (y being the up-vector)? Then based on where a person is in the world, they could only collide with objects in the linked list of the spot in the world they are at, or adjacent ones. That would eliminate about 99% of all game objects from collision tests. Any thoughts?
Offline kevglass

« JGO Spiffy Duke »

Medals: 319
Projects: 25
Exp: 22 years

Coder, Trainee Pixel Artist, Game Reviewer

« Reply #1 - Posted 2004-01-04 06:05:33 »

This is part of how I spatially partition my current game world. It works fine but thats really to do with the type of map I'm working with. If most of your map spread is width and depth this should be enough.


Offline Jeff

JGO Coder

Got any cats?

« Reply #2 - Posted 2004-01-13 02:04:41 »

Another common approach is a nested tree of bounding volumes.

Got a question about Java and game programming?  Just new to the Java Game Development Community?  Try my FAQ.  Its likely you'll learn something!
Games published by our own members! Check 'em out!
Legends of Yore - The Casual Retro Roguelike
Offline princec

« JGO Spiffy Duke »

Medals: 1033
Projects: 3
Exp: 20 years

Eh? Who? What? ... Me?

« Reply #3 - Posted 2004-02-04 08:37:05 »

All collision detection algorithms between n objects ultimately execute in ((n-1)*(n-1))/2 time. No matter which way you slice and dice the problem with clever and fiddly linked lists and octrees you will always end up doing at least ((n-1)*(n-1))/2 collision detection tests, whether it being direct collisions or classification of objects beforehand into octree nodes.

You can gradually tend towards an n log n time algorithm by using tricks like octrees but the added complexity and overhead means this only becomes viable as n grows very large.

My advice, therefore, is to go with the simplest approach you can get away with, and make sure that you can change your approach if you find that there is a bottleneck in collision detection. Brute force is perfectly acceptable for a couple of hundred objects per frame.

Cas Smiley

Pages: [1]
  ignore  |  Print  

EgonOlsen (78 views)
2018-06-10 19:43:48

EgonOlsen (58 views)
2018-06-10 19:43:44

EgonOlsen (78 views)
2018-06-10 19:43:20

DesertCoockie (260 views)
2018-05-13 18:23:11

nelsongames (158 views)
2018-04-24 18:15:36

nelsongames (157 views)
2018-04-24 18:14:32

ivj94 (898 views)
2018-03-24 14:47:39

ivj94 (162 views)
2018-03-24 14:46:31

ivj94 (811 views)
2018-03-24 14:43:53

Solater (175 views)
2018-03-17 05:04:08
Java Gaming Resources
by philfrei
2017-12-05 19:38:37

Java Gaming Resources
by philfrei
2017-12-05 19:37:39

Java Gaming Resources
by philfrei
2017-12-05 19:36:10

Java Gaming Resources
by philfrei
2017-12-05 19:33:10

List of Learning Resources
by elect
2017-03-13 14:05:44

List of Learning Resources
by elect
2017-03-13 14:04:45

SF/X Libraries
by philfrei
2017-03-02 08:45:19

SF/X Libraries
by philfrei
2017-03-02 08:44:05 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‑
Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines | Managed by Enhanced Four Valid XHTML 1.0! Valid CSS!