OTOY Forums

This has been bothering me for a bit. I'm trying to render out a texture coordinate pass (aka in C4D a UVW pass) of an object, and its corresponding alpha. When I render these two passes of the object out using Octane multi-pass, they don't line up. They're off by a few subpixels, but thats enough to create a seam when using the texture pass to retexture an object in post. They're off by just a few pixels, and I can't figure out why! Its maddening. Does anyone have any suggestions?

example; notice the red edge and the green edge. That green edge is the UVpass of another object that I don't want. This whole image is being cropped by the alpha that was rendered along with this texture pass, so as you can see, they don't line up because you can see that slight green line:
And here's my render settings: I need these two passes to line up down to the subpixel level. It looks like there's anti-ailiasing going on, but I don't see any other place I could turn something like that off.

Anyone? Ahmet?

do these both are generated from Octane?

Yes. That's why I'm so confused. Shouldn't they line up perfectly if I've turned off anti aliasing?

here's the project file:

It's a Octane render issue. Someone asked about this in standalone forums. I'm not sure why it cannot fit exactly. But Thomas made some explanations for this as i remember that.

Well, to me it looks like more anti-ailiasing is applied to the render layer masks than the beauty pass, even if you turn off anti-ailiasing in octane and/or C4D. Can you think of any workarounds for this at the moment?

Hi,

Thanks for the detailed report. We reproduced the issue from your file and it will be fixed in the next release.

The bug was that we use double the pixel filter radius for the info passes than for the regular render passes. If you can live with blurred edges, you can work around this by setting the filter size for the kernel twice the value as the one configured for the info passes.

cheers,
Thomas

Thanks Thomas! I'll try this later tonight. As long as I can get the two passes to line up pixel per pixel then I'm fine with blurred renders (I just need the UV data to retexture an object post render). I was planning on doing a tutorial involving 360 content, Octane/C4D, and After Effects, but with this issue, I'll have to hold off until v3.

dotcommer wrote:Thanks Thomas! I'll try this later tonight. As long as I can get the two passes to line up pixel per pixel then I'm fine with blurred edges. I was planning on doing a tutorial involving 360 content, Octane/C4D, and After Effects, but with this issue, I'll have to hold off until v3.

Version 3 is still a while off. This bug will be fixed in 2.23, which may be released in a week or two.