Simple Code Practice.

thanhquan1512

Hi folks,

I have some problems that is need your help because I don't know my current practices are okay.

1.With collision detection, currently I used a simple collision detection based on sprite and no need to create a physics body, like this:

function self:collidesWith(sprite2) local x,y,w,h = self:getBounds(stage) local x2,y2,w2,h2 = sprite2:getBounds(stage)   return not ((y+h < y2) or (y > y2+h2) or (x > x2+w2) or (x+w < x2)) end

I wonder if I use this method, does the game run better compared to method which use physic body? In this method we can only process square object, circle object with transparent edge will return invalid result. Any ideas to to correct this?

2.In my game, I use onEnterFrame event and frameCount to manage movement. In each enter frame event, I must loop around all object in a parent sprite (called group) then process it's movement. Is this a good practice?

3.I find my game speed is ok without sound. With sound added, every time sound channel start to play, the game is a bit freeze. Any help to avoid this?

Thank you very much

ar2rsawseen

@thanhquan1512 this collision method is faster than box2d physics, but yes it can deal only with squares. If you'll try to apply something more sophisticated, it won't be as quick as it is now.
If you really want proper (and fast) collision detection, you should try TNT Collision engine.
http://www.tntparticlesengine.com/?cat=15

It makes sense to use box2d only when you need physics simulation, not for collisions.

And about sound, do you use wav for sound effects? Cause by the description it seems that you are using mp3 (it takes time to decode it, thus the delay), so try using wav files for quick sound effects and mp3 for background music

atilim

1. I think both TNT Collision and box2d collision testing will perform better then pure Lua. For example, with this sample code I'ved use box2d for collision testing: http://giderosmobile.com/forum/discussion/2318/ios-player-issue#Item_4
2. Yes, it's really good practice.

Tom2012

I use TNT Collision engine and it's been a great find.

http://www.tntparticlesengine.com/

thanhquan1512

Thank all, I learned a lot from your experience, your fast support is 1000 times valuable than a long list of documentation, that's why I love Gideros