★ TouchArcade needs your help. Click here to support us on Patreon.

How to make glow effect in cocos2dx

06-01-2014, 08:10 AM
#1
Junior Member [Original Poster]
Joined: Dec 2013
Posts: 10
How to make glow effect in cocos2dx

i searching the web for glowing effect , i like to be able to create misc glowing effects ,
like lasers , glow around sprites and such .
couldn't find any thing on the web , any body have any direction ?
something like this :

Last edited by Umen; 06-01-2014 at 08:28 AM.
06-01-2014, 10:55 AM
#2
Joined: Apr 2013
Location: Seattle
Posts: 91
One simple way is to make a copy of the sprite image. Change it all to white. Apply a nice blur to it (all of that in a graphics program), then add the glow sprite behind the main sprite.

If you use white, then in code you can simply tint the glow to whatever color you need.
06-01-2014, 12:26 PM
#3
Junior Member [Original Poster]
Joined: Dec 2013
Posts: 10
Good idea

i was wandering if it can be done combining shaders , what is better ?
06-02-2014, 03:35 AM
#4
Blur shaders can be hefty due to needing to do multiple samples of a texture (depending on the size of the blur) and you also need to account for the fragments in the sprite (number or samples x number of fragments). On a desktop GPU this is not an issue but on a mobile it adds up fast. I did a basic one way blur effect recently and only got to 4 samples before it started getting a bit dicey on an iPad 2.

Your best move (as noted above me) is to preprocess the glow effect in a sprite. Now, whether you do that as an art asset or by using a blur shader to render to an FBO (do it during startup) is up to you. Easiest way is an art asset.

Rogue Agent Developer
Tweet me! @StephenRBerg

Last edited by Rogue; 06-02-2014 at 03:39 AM.