topic Re: MtoA incorrectly rendering perspective projections in Arnold for Maya Forum

MtoA incorrectly rendering perspective projections

GiancaYard — Sat, 26 Nov 2022 21:37:53 GMT

I tested this bug on MtoA from 5.2.2 to as back as 5.0, and this issue is easily and consistently reproducible on Maya 2020, 2022, and 2023.

When using perspective texture projections, Arnold renders the projections incorrectly: apparently, it fails to obey the "projection1.fitType" (Match Camera Fill Gate/Resolution) flag, and perhaps other issues.

In other words, it prevents camera projections from matching what is the Maya's viewport unless the rendering resolution matches the aspect ratio of the projections.

In the first two screen grabs, you can see the texture projection displaying as expected: the Arnold render and the viewport match. However, before taking the third screen grab, I changed the render resolution from 1024x1024 to 1024x512, and the texture projection behaved differently, even as I changed *nothing else* but the render resolution.

It seems that Arnold texture perspective projections only work with "Match Camera Fill Resolution" mode with the fill value as horizontal.

Re: MtoA incorrectly rendering perspective projections

delapazr — Wed, 01 Feb 2023 20:24:26 GMT

Curious to find out if you found a solution, since I am having the same or a similar problem. I am trying to use a cylindrical projection, which looks correct in the viewport, but when Arnold renders it, it is distorted. I discovered that the distortion matches what the projection looks like if I switch to a spherical projection. I have attached an image illustrating this.

Re: MtoA incorrectly rendering perspective projections

GiancaYard — Thu, 16 Feb 2023 20:46:07 GMT

I think this issue you are having is different: in your case, Arnold is not obeying the kind of projection you are trying to use and defaults to the spherical one.

In my case, the projection type (perspective) is correct in Arnold, but the aspect ratio of the original image is not.

My solution, for now, is to use Redshift instead of Arnold, which works perfectly fine.

Re: MtoA incorrectly rendering perspective projections

sebastien.blaineau.ortegaHRM3U — Fri, 17 Feb 2023 08:30:31 GMT

Thanks for reporting this giancarlo, we can reproduce the issue.

We created ticket MTOA-1319 to address this.

Cheers