[Forage]

I love the following stuff in case you are still looking for improving the list:

• https://www.shadertoy.com/view/4dl3zn
  
• https://www.shadertoy.com/view/4dBSRK
  
• https://www.shadertoy.com/view/Xd2GR3
  
• https://www.shadertoy.com/view/lss3Df
  
• https://www.shadertoy.com/view/Ml2GWy
  

Note: on Pi1/Pi2 you can handle about 1000 cycles worth of work per pixel and have a decent framerate.
Complex operations like sin/cos/sqrt will take dozens of cycles. Shaders that have loops with high iterations are likely to struggle.
From your list the first one is probably out (loop of 40, then several calls to complex operations inside that loop).
The others look more plausible.

Many thanks for the guide. It helps now that you made it as an add-on as well.
Funny how only the ugliest one from the list (number 2) actually works and the rest is just too heavy for a RPi

Now that it's an add-on, is there a way to add and remove items from the list instead of having to replace existing ones? I didn't find a config file which includes the list with the names, but just in case I overlooked something. Not that it's a big deal, it's just for playing, I was just wondering.