Quick Q on transform feedback shaders (ParticleSphereGPU sample)

Using Cinder
1

hi there,

its not entirely clear to me how i can pass per-vertex data between the transform feedback shader and the vertex shader.

this seems to be done behind the scenes for ciPosition and ciColor, but how do i create my own in from the transform feedback shader?

basically im calculating the gl_pointSize in my transform feedback shader and i need to set it in the vertex shader. any suggestions?

cheers.

2

Have you looked at the TransformFeedbackSmokeParticles sample that comes with cinder? It shows how to setup varyings to a transform feedback shader.

3

wow, thats exactly what i needed… no idea how i missed that!
thanks again @lithium for your help.