Node Precomputation

Archive User Feedback
1

Do Cycles nodes support previews and precomputation?

If not are there plans or suggestions to implement this?

2

Cycles does not support node previews in the node editor, if that’s what you’re asking.

Not sure what you mean “precomputation” though.

3

When the render is started is the node calculated for every sample or is there a function to compute some data at the start of the render. E.g. is the colorramp sampled once or multiple times?

4

It depends. If we can detect that it has a constant value we sample the node once, if it’s potentially different for every pixel we need to sample it for every pixel.

5

If it’s a constant value where in the cycles code should this go?

6

here is the one for the ramp, but it’s done on a node by node basis.

7

Thanks I’ll take a look at how it’s done.