Z fidelity using RT Cuda

[ricoholmes]

edit note: The zdepth I'm talking of here is ridiculously fine, so in all fairness it's unreasonable to expect it to work at all.

Hello,
Just wondering if I'm missing a switch while rendering with CUDA. The only problem I've been experiencing recently is some clipping related to zDepth (not the render element, but the camera).

sample scenario: rendering PET containers (very thin plastic) where the fluid is clipping through the walls of the of the containers. They render perfectly fine with CPU, though I suspect the fidelity isn't fine enough in GPU. The viewport looks correct, but then again we've set the camera near/far to more appropriate units for that. Is there anything I can adjust regarding this for GPU rendering ?

I've seen similar issues with other scenarios (headaches with condensation droplet intersections). GPU is proving amazingly good for most production shots these days

[Svetlozar Draganov]

I am a little bit lost here, is the result expected or not?
Can you send us some images/scenes so we could understand better what exactly the issue is?

Thank you very much in advance.

[ricoholmes]

Hi Svetlozar, sorry for the delayed response. Short answer: nothing to worry about.
Actually, I pulled apart the scene and realised, if anything, the GPU is too good ;p. I had assumed that because the CPU rendered the fluids apparently inside the plastic, the CUDA renders were faulty. It turns out the fluid mesh was clipping through (not noticeable on the CPU renders ?). I have a "visible in refractions" toggled off for condensation droplets in some cases that misbehave on GPU when very close to the surface, but I'm going to work around that.
When done with the project I'll see if I can cut it back to the problem areas and send a scene (currently NDA)