cocos2d for iPhone

A fast, easy to use, free, and community supported 2D game engine

1. 

   moby
   Member

   I've been using particle systems in various forms for a while, yet this new issue has stumped me.
   I have a game where i add a bunch of particle systems to an nsmutabledictionary during my setup method (to initialize them), and then access them as needed by key from the nsdictionary. this technique is done to "preload" all the particle systems to avoid lag during runtime. It works great. but i am noticing a very subtle problem.
   The first time i run the game, the colors in the particle system are as expected.
   the next time i run the game (i'm not exiting the game, merely rerunning it), all the particle system colors are a lot lighter, as if they had a lot more luminosity.
   It might have something to do with my open gl blend mode settings, but even if that were the case, i would expect the behavior to be consistent so all iterations of the game would have a lighter shading for the particles. it's strange that the first iteration is normal, but then all ensuing ones have a lighter pallete.

   has anyone experienced something similar and can shed some advice?

   thanks
   m0by

   Posted 1 year ago #
2. 

   finder39
   Member

   which version of cocos2d?

   Posted 1 year ago #
3. 

   moby
   Member

   latest and greatest 0.99-3

   Posted 1 year ago #
4. 

   finder39
   Member

   I had issues with it, as to why i kept with 0.99.0-FINAL even though i lost $8 on the particle designer. I found issues with particles in 0.99.3, mainly with the fireworks one being discolored. try 0.99.0 and see if you have same issue

   Posted 1 year ago #
5. 

   riq
   Key Master

   @moby:

   try this:
   

   emitter.blendFunc = (ccBlendFunc) {GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA};

   It seems the previos versions under certain condition where not using the correct blending function.
   Could you post the code to reproduce your issue ?

   Posted 1 year ago #
6. 

   finder39
   Member

   that works :) it gets everything back to normal, at least for me :)

   Posted 1 year ago #
7. 

   moby
   Member

   through trial and error and examining the cocos2d code, i arrived at a similar conclusion - namely the fact that the blending functions were out of whack. i had transitioned to using particle designer (excellent app) and upon closer scrutiny realized that my blend functions were all over the place. i changed them to gl_src_alpha and gl_one_minus_src_alpha and saved that to the various particle plists, imported them into cocos2d and the problem disappeared.

   Posted 1 year ago #
8. 

   riq
   Key Master

   @moby:

   Try to avoid setting blend functions manually. Instead set the blend src/dst functions in the nodes. Most nodes supports the blendFunc property.

   Posted 1 year ago #
9. 

   moby
   Member

   thanks riq. i'll follow your advice.
   btw, i have a related post on some of the issues with particle designer + cocos2d over on 71^2 if it helps anyone:
   http://www.71squared.com/community/viewtopic.php?f=22&t=157&start=0
   m0by

   Posted 1 year ago #

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