Hi !
Featured games (84)
games approved by the League of Dukes
Games in Showcase (604)
Games in Android Showcase (171)
games submitted by our members
Games in WIP (652)
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  
  Best way to sort through giant lists?  (Read 1627 times)
0 Members and 1 Guest are viewing this topic.
Offline cubemaster21
« Posted 2013-03-15 19:52:45 »

I have a list of about 1000 entities that i need to go through on a regular basis and see which ones are in a certain range. However, looking through the list every time I need to get the new list seems a bit inefficient. Is there a better way to do this? This is somewhat of what I'm using now.
public ArrayList<Entity> getEntitiesInRage(int range, Entity center){
     ArrayList<Entity> inRange = new ArrayList<Entity>();
     for(Entity e: fullList){
          if(e.getDistanceTo(center) >= range)
     return inRange();


Check out my game, Viking Supermarket Smash
Offline HeroesGraveDev

JGO Kernel

Medals: 360
Projects: 11
Exp: 3 years

┬─┬ノ(ಠ_ಠノ)(╯°□°)╯︵ ┻━┻

« Reply #1 - Posted 2013-03-15 19:59:11 »

lol. Grin


The only way to optimise such a method is to put the entities into a large-scale grid*. Then you can work out the maximum amount of grid squares you could go and still be in that range. Then you check all the entities within those grid squares, and do the final check on only those entities.

You would have to store which entities are in which grid. And make sure that when one moves, it is removed from the previous square and added to the next.

*Grid or Tree

Offline cubemaster21
« Reply #2 - Posted 2013-03-15 20:06:38 »

Lol, that was just some psuedocode. I didn't even catch the 'Rage'. Anyway, I don't think that there is any real way that I could get them into a grid system.

Check out my game, Viking Supermarket Smash
Games published by our own members! Check 'em out!
Legends of Yore - The Casual Retro Roguelike
Offline HeroesGraveDev

JGO Kernel

Medals: 360
Projects: 11
Exp: 3 years

┬─┬ノ(ಠ_ಠノ)(╯°□°)╯︵ ┻━┻

« Reply #3 - Posted 2013-03-15 20:19:48 »

You could if you really wanted to. Smiley

Offline cubemaster21
« Reply #4 - Posted 2013-03-15 20:22:08 »

Instead, I've just decided to reduce to list size to 250 and whenever the size gets any smaller, it just adds some to fill in the gaps.

Check out my game, Viking Supermarket Smash
Offline pjt33

« JGO Spiffy Duke »

Medals: 40
Projects: 4
Exp: 7 years

« Reply #5 - Posted 2013-03-15 21:56:58 »

Lol, that was just some psuedocode.
That's good, because the logic's back to front as well.

Do you really need to find all entities within range, or would you be better using something like k-nearest, which is a well-discussed computational geometry problem?
Pages: [1]
  ignore  |  Print  
You cannot reply to this message, because it is very, very old.

SHC (24 views)
2015-08-01 03:58:20

Jesse (19 views)
2015-07-29 04:35:27

Riven (40 views)
2015-07-27 16:38:00

Riven (21 views)
2015-07-27 15:35:20

Riven (24 views)
2015-07-27 12:26:13

Riven (14 views)
2015-07-27 12:23:39

BurntPizza (36 views)
2015-07-25 00:14:37

BurntPizza (46 views)
2015-07-24 22:06:39

BurntPizza (28 views)
2015-07-24 06:06:53

NoxInc (36 views)
2015-07-22 22:16:53
List of Learning Resources
by gouessej
2015-07-09 11:29:36

How Do I Expand My Game?
by bashfrog
2015-06-14 11:34:43

List of Learning Resources
by PocketCrafter7
2015-05-31 05:37:30

Intersection Methods
by Roquen
2015-05-29 08:19:33

List of Learning Resources
by SilverTiger
2015-05-05 10:20:32

How to: JGO Wiki
by Mac70
2015-02-17 20:56:16

2D Dynamic Lighting
by ThePixelPony
2015-01-01 20:25:42

How do I start Java Game Development?
by gouessej
2014-12-27 19:41:21 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!