shaders on shaders

[garrisonhh]

would be really cool if shaders could sample their previous frame. it would also be interesting to allow shaders/hydra to sample other shader/hydra output, but I have no idea how messy that would be to implement

[TristanCacqueray]

Perhaps we could start by figuring out how to hook the shader canvas as a hydra input, that way we can use hydra for such effect. I think we might have to move the shader code to the hydra iframe to allow them to share their canvas.

[felixroos]

ive implemented shader feedback here: https://github.com/felixroos/schattenspiel look for iFeedback