Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: Richy on 2014-06-16, 09:17:53

Title: Faceted bump render
Post by: Richy on 2014-06-16, 09:17:53

Hi, this is simple sphere with bump map, and i can't remember how to solve this.

Thanks!

Title: Re: Faceted bump render
Post by: ecximer on 2014-06-16, 09:25:14

add mesh smoothing iterations.

Title: Re: Faceted bump render
Post by: Richy on 2014-06-16, 10:06:36

Subdivided mesh, but got just smaller facets.

Title: Re: Faceted bump render
Post by: Captain Obvious on 2014-06-16, 11:21:27

There is no real solution for it. You'll have to reduce the bump strength and increase the mesh smoothing.

Title: Re: Faceted bump render
Post by: crazyman on 2014-06-16, 11:53:41

Show mat settings. Are you sure you did not apply normal map as bitmap, or opposite bump bitmap as normals?

Title: Re: Faceted bump render
Post by: Richy on 2014-06-16, 12:37:51

Quote from: crazyman on 2014-06-16, 11:53:41

Show mat settings. Are you sure you did not apply normal map as bitmap, or opposite bump bitmap as normals?

I just plugged procedural noise into bump slot.

Title: Re: Faceted bump render
Post by: Captain Obvious on 2014-06-16, 13:07:44

This isn't a bug or anything. It's called the terminator problem, and you can read some about it in this PDF: http://geekshavefeelings.com/x/wp-content/uploads/2010/03/Its-Really-Not-a-Rendering-Bug-You-see....pdf (http://geekshavefeelings.com/x/wp-content/uploads/2010/03/Its-Really-Not-a-Rendering-Bug-You-see....pdf)

Basically, what's happening here is that the strong bump map is increasing the effect. You need to A) reduce the strength of the bump and B) increase the tessellation of your sphere. Eventually it won't be noticeable any more.

Title: Re: Faceted bump render
Post by: crazyman on 2014-06-16, 13:12:49

OR just use displacement instead bump

Title: Re: Faceted bump render
Post by: Richy on 2014-06-16, 13:18:09

Thanks!

Title: Re: Faceted bump render
Post by: Captain Obvious on 2014-06-16, 13:39:33

Quote from: crazyman on 2014-06-16, 13:12:49

OR just use displacement instead bump

Yes, that works too because it actually generates additional polygons, instead of just changing the normals. But you can still get this problem with displacements, if your displacement subdivision rate is too coarse.