Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Bug Reporting => Topic started by: arqrenderz on 2021-03-01, 16:38:50

Title: Weird sampling bug related to round corner legacy
Post by: arqrenderz on 2021-03-01, 16:38:50

Hi i have found some weird issue related to round edges and the legacy - precise option.
We were making some 8k*8k vr tours and found these strange round cirles on the walls, i manage to reproduce the problem and the one to blame here is the legacy or pricese option on the corona round edges, if i unthick those the circles dissapear, Its not a matter of sampling or insufficient render passes.

Attaching some screens and a scene to reproduce the bug
Uploaded scene trough corona private uploader dropbox , name Look dev v1 BUG round cornernoise.7z


(https://i.ibb.co/tC7VvQw/2021-03-01-103403.png) (https://ibb.co/j4cnQb9)

Title: Re: Weird sampling bug related to round corner legacy
Post by: rowmanns on 2021-03-02, 12:48:23

Hi,

Which versions of Corona and 3ds Max are you using?

Thanks,

Rowan

Title: Re: Weird sampling bug related to round corner legacy
Post by: arqrenderz on 2021-03-02, 14:15:41

its max 2021.3 and corona 6.1, Win 10 updated

Title: Re: Weird sampling bug related to round corner legacy
Post by: rowmanns on 2021-03-17, 12:10:31

Hi,

Sorry it's taken me a while to get back to you.

I have tried your scene in both v6 HF1 and the latest daily build and I cannot reproduce this bug. The scene renders pretty much the same whether the round edges is in precise, fast and whether legacy is enabled or not..

I have attached some screenshots.. Is there something I'm doing incorrectly?

Are you able to send over the original scene from which you posted the image above?

Cheers,

Rowan

Title: Re: Weird sampling bug related to round corner legacy
Post by: arqrenderz on 2021-03-17, 15:25:52

Hi Rowmanns, here is a screen and a little change for the scene, just use the doll camera tool to get a little closer to the box until you see the effect, and use the reflection pass omstead of beauty, the effect is more visible there.
Im also attaching another screen and the modified camera on the same 3dsmax file.

Title: Re: Weird sampling bug related to round corner legacy
Post by: rowmanns on 2021-03-19, 20:48:28

Hi,

Thanks for the second scene. We can reproduce the issue now, but only when the legacy mode is enabled.

Is there some reason why you need to use the legacy mode? Would a suitable workaround be to disable the legacy behaviour?

Thanks,

Rowan

Title: Re: Weird sampling bug related to round corner legacy
Post by: arqrenderz on 2021-03-19, 21:28:41

I was using it to avoid having round corners on surfaces flat surfaces that had some kind of subdivision going on, or intersections with other materials and meshes.
But im updating my shaders to avoid that circle, it was a big mess on those 8*8k VR lol

Title: Re: Weird sampling bug related to round corner legacy
Post by: arqrenderz on 2021-03-30, 19:17:50

I found the case were the precise or fast option give a bad result and the legacy one is the only that works.
Here is a wall and a ceiling that are 2 separate elements but it could be anything else, the fast and precise options will show that seam. the legacy one will not.

(https://i.ibb.co/VWfrcKj/fast.png) (https://ibb.co/hR3hJq7)

(https://i.ibb.co/42Tdp55/precise.png) (https://ibb.co/1Mq6Tww)

(https://i.ibb.co/GFj61NN/Legacy.png) (https://ibb.co/1bxgpjj)

For me that option is super important, otherwise all sorts of bad things will happen on interior renderings.

Also just discovered that the bug occurs when i use a noise in the radious slot