Maya Octane plugin Light trouble

Wed Dec 02, 2015 12:53 am

Good afternoon, I have a question on account of light in a plugin for Maya, why it does not work properly?
Maya 2016:

Cinema 4d R15:

If the same size and configuration results in a Cinema 4d and Maya are very different, why is this happening?
Thank you for attention

Wed Dec 02, 2015 1:04 am

In C4D plugin, lights are built from a movable(indivual) geometry + emissive material. Emissions in indivual meshes and static meshes can be different. Because several meshes are exported as a part of big mesh, illumination will be calculated by a ratio of emissive meshes against total mesh area.
If it's exported on similar way at the end and has same parameters should be same. You can compare the resulting data in Octane Node graph or Standalone.

Wed Dec 02, 2015 10:35 am

What about black radial lines, what is it? These lines can be well seen on ambient occlusion pass, and this bug depends on the distance of the object from the camera ((
[youtube]https://youtu.be/aEOLMkh56I4[/youtube]
[youtube]https://youtu.be/8tN04Eii7i8[/youtube]

Thu Dec 03, 2015 2:52 am

akvahouse wrote:What about black radial lines, what is it? These lines can be well seen on ambient occlusion pass, and this bug depends on the distance of the object from the camera ((
[youtube]https://youtu.be/aEOLMkh56I4[/youtube]
[youtube]https://youtu.be/8tN04Eii7i8[/youtube]

It's not a bug. A limitation of float-point math. Octane use floating-point calculations not double precision numbers. I hope you know what means this. This is similar to opengl's behaviour on large scenes with small details. It can be adjustable via "Ray Epsilon" in current kernel. It's one kind of threshold value for math errors or a scaling factor.