The Heeelix demo has been ported to GeeXLab (OpenGL 2.1). I didn’t test on all platforms but this demo should run on Windows, Linux, macOS. In theory, it should be work on Raspberry Pi but in practice, I think the pixel shader is a little bit too heavy for the VideoCore IV GPU.
Heeelix won the first place at the Revision 2018 party animated gif compo.
The pixel shader is ready to be live-coded. Just run the demo (gl21-heeelix.xml) in GeeXLab, edit the pixel shader in your favorite text editor and hack the demo!
For any feedback, a thread on Geeks3D forums is available HERE.
On my GTX 1080, it takes around 2 seconds to compile the GLSL pixel shader each time you add a new modification. If the modification is already known by the GLSL compiler, the update is extremely fast.
Heeelix runs at 174 FPS (res: 800×480) on a GeForce GTX 1080 + R391.35.
If you uncomment the line 14 of the pixel shader (ANOTHER_LEVEL) you will get:
And if you add two extra levels:
#ifdef ANOTHER_LEVEL scale *= pModHelixScale(p, lead, innerRatio); p.x *= -1.; scale *= pModHelixScale(p, lead, innerRatio); p.x *= -1.; scale *= pModHelixScale(p, lead, innerRatio); p.x *= -1.; #endif