I’m having some problems rendering a scene that includes loads of foliage (static camera). The result I’m after is having 2 videos (or img sequences), one containing the final color pass & one containing the depth pass.
Using 32-bit made things super slow, so I’m now going for 8bit renders. Losing some of quality for the depth pass here, but having tested this it turns out it’s completely usable for my needs.
Couldn’t find a way to use UE’s native z-depth pass for rendering in 8bit, so I’ve found a way to use a custom material (with tweakable z-start/end sliders), and found another way to normalize it so it stays in the 0-1 range, so I can render it in 8bit. (For some reason png sequences renders completely black for the depth pass, so I’ve had to use jpg sequence for that, adding unnecessary compression, but let’s say that’s fine.)
The problem I’m facing now is with antialiasing. I have loads of foliage in the scene, so temporal antialiasing (TAA or TSR) are the only ones that work nicely. The problem is temporal antialiasing causes my depth pass to be super jittery for some reason (although the camera is not moving), making it completely unusable. If I switch to FXAA or MSAA, the depth pass is no longer jittery, but then all the foliage in the color pass becomes jittery AF, making the color pass unusable.
So I’ve come up with a few possible solutions, but no idea how to implement them:
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find a way to render UE’s native depth pass, in a normalized way (0-1 range, so I can save it in 8bit), instead of using a custom depth material. There’s a project setting that should disable TAA jittering in the depth pass, but that doesn’t work when using a custom material as depth.
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find a way to switch between antialiasing settings per render pass (but I doubt that’s possible)
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find some way to use time-dependent seeded noise for the foliage wind, so the animation of the foliage is dependant on the timeline (as default it’s completely independent). If I manage to do that, instead of doing one render with two passes, I could just do two individual renders and tweak those settings accordingly.
Any way to do either of those things?