[Interest] 60FPS and FBO

[Thomas Senyk]

Hi,

the context of this is mail is:
 - scenegraph
 - FBO based effects
 (plain shader-effects, qtgraphicaleffects, qt3d)
 - embedded hardware / opengl es 2.0


I've noticed that on a lot of embedded systems the FPS drops rather 
drastically (e.g. from 60 to 30 with one effect, from 30 to 10-15 with two 
effects) when using FBO based effects.
  ... even simple effects, sometimes even if they have 'visible: false'

Is this somewhat expected?
It does sound like a vsync vs. fbo problem ... doesn't it?
Is this a fault/bug in the embedded opengl drivers?

Did anyone ever had a setup, using one or multiple FBO based effects did still 
result in 60fps? (as it should be for simple(!) effects?)



This mail is 'vague' on purpose, I don't want to start a concrete technical 
discussion ... I rather want to ask for opinion and experience.


Greets
Thomas