Author Topic: Reflection Issue / Wrong in VFB / Correct results in Interactive Render  (Read 564 times)

2020-10-25, 16:29:00

ASIMO

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Hello

I am struggling with a major problem. Since years I build and render buildings with the same workflow. I never had this kind of problem.

I have a simple model of a facade. When I render with interactive render mode everything looks alright and as it should be.

Starting the render inside the VFB the reflection is in some parts completely broken. It almost looks as if bended / distorted.

Also I noticed that the reflection breaks along the polygon lines.

You see it in the lower glass panels as well as in the green facade panels, where the reflection goes missing. One green panel is just dark.
_

I work with Cinema4D 18 and Cinema4D 22 and have tried to render with Corona V5 and V6.

This is a very strange behavior as in interactive mode Corona-Render does the right job ?

Attached there are two screenshots. Also there is the scene I use.

Thank you very much for your suggestions and help.

best – David
« Last Edit: 2020-10-25, 16:35:23 by ASIMO »

2020-10-25, 20:37:56
Reply #1

Cinemike

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Hi ASIMO,

give all your reflective and plain areas a phong angle of 0° (you have 30° on the green glass there now). This should fix your issue.

CU
Michael
« Last Edit: 2020-10-25, 20:53:43 by Cinemike »

2020-10-25, 21:06:35
Reply #2

Cinemike

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As for the other glass elements, the problem lies in the topology. Green (from the mesh checker) points at "boundary edges", which aren't actually connected to each other, causing refraction and refraction issues (the panes are "put together").
A possible solution would be using "thin glass" instead of the refractive one in your scene.

CU
Michael

2020-10-26, 09:13:09
Reply #3

ASIMO

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Thank you very much Michael

I followed you advice and you are right. Changing the phong for the green panels worked !

Regarding the glass it did not – maybe because it also affects refraction as well ?

But more important : You pointed out a geometrical problem. Excluding this corner from the scene did the trick. So it is obvious that the error seems geometry-based.

Without the corner-element glass and panels are looking fine now. So I have a solution.
_

But still interesting : Why is it correct when using interactive render ?

Do you have an idea ?

Thank you so much

best – David

2020-10-26, 15:59:02
Reply #4

Cinemike

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But still interesting : Why is it correct when using interactive render ?

Do you have an idea ?

Thank you so much

best – David

I am glad I could help you with a solution.
But I don't have the slightest idea why the IR renders so differently and much more tolerantly. This is a questions for the Corona team to answer.