Bevel modificator causes refraction deformation

[LeSill]

Hi,

I recently ran into an issue with the BEVEL MODIFICATOR. It creates HDRI background deformation as soon as it is applied to a plate of glass in a window. When I enable the break phong shading features, it helps somewhat. However, that should not have happened in the first place.

[Beanzvision]

Hi there, do you have subdivisions enabled in the bevel mod? This was the only way I could reproduce this.

[LeSill]

Yes, I have the subdivisions enabled.

[Beanzvision]

Okay. Is that needed? What exactly are you trying to do to the glass panel?

[Cinemike]

Have you tried to reduce the Phong angle, like really, really lower it?

[LeSill]

Of course, I can take this modificator off the glass panel. I just wanted to mention that there is a glitch that may affect not only specular materials but also other geometry if the bevel modificator is used.
Because I was unaware of the problem, I placed the bevel mod beneath a null object where other elements of the window frame were. Then I struggled for a while to figure out the problem.

[romullus]

This is not glitch, nor Corona bug, it's just how smoothing shading works. It's the same in 3ds Max, or in any other 3D program that works with polygonal mesh. There are many ways how to fix this "issue", some of which were already listed above, but the best way would be to learn basic surface shading principles, so you would know what's causing this behaviour and what to do to avoid problems with that in the future.

[LeSill]

OK. I will check the shading rules to avoid it next time. Do you have any link where I could find more info?

[Cinemike]

OK. I will check the shading rules to avoid it next time. Do you have any link where I could find more info?

The Online help. Phong tag.
There you can read WHY reducing the phong angle would have helped and much more.
I've also attached a file to play with. Increase/decrease the phong angle and watch what happens, also switch "use phong breaks" on and off. The phong mystery is best solved by trying. It's what other apps call "soft shading" or "smooth shading" or whatever.

PS
For glass panes, always use a very low phong angle unless you want "spherical distortions".

[LeSill]

Thank you for your reply. I will check it.

[tiglat_agora]

Hi Le Sill,

have you tried the option in my attachment?

regards
Bastian

[LeSill]

Hello,
now that I know what's causing the distortion, I'll use the Phong Break Rounding option. I was simply surprised that you needed to use it. It's a shame that BEVEL MODIFICATOR doesn't provide an option to remedy the shading problem without breaking the phong rounding. The bevel modif, for example, could add next sections next to the rounded edges. When I utilize the Phong Break Rounding option, I lose the right smooth behavior on a diffuse material.

[James Vella]

Isnt that why they have the phong break rounding button in the bevel modifier?

[LeSill]

No, I don't believe so. When I check this box and observe the shade on the rounding's border, it just destroys the smoothness between the rounding edge and the rest of the geometry. But isn't this not natural behavior in the real world? I'm looking for a seamless transition/shading between two perpendicular surfaces. The problem could be solved if the bevel mod made extra cuts at the rounded edge.

[James Vella]

Cant you just use that in conjunction with Phong Break Miters (the button below)?

I dont really see much difference between using those 2 and default 3dsmax chamfer (bevel).

C4D


3dsmax