Rendering changes in R21?
Posted: 20 November 2019 04:54 AM   [ Ignore ]  
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I modeled an assembly line R20, lit and textured it successfully. Then used the symmetry object to replicate it across the factory floor. In R20, everything looked as expected. I used an infinite light with ambient fill. Standard stuff.

I opened the same model in R21 and the textures and lighting went crazy. Most of the surfaces turned black, and the reflections/refractions in the glass, and reflection from the steel surfaces became totally deranged. The symmetry object created what appear to be very unusual UV mapping/phong effects in which geometry and ngons that were formerly invisible, now appear in the render. Very distressing.

I assume that this is due to changes in the way R21 handles materials and lights. I can’t share the model but am hoping you can diagnose the fundamental misstep from the description. Can you point me to the solution? Is it (again) a missing check box?

I would have sent images but after an hour of trying I couldn’t get them small enough to satisfy the pixel sheriff. Will try again if you need them. My expectation is that the solution is obvious to the trained professional.

Thanks.

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Posted: 20 November 2019 09:44 AM   [ Ignore ]   [ # 1 ]  
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Hi mford610,

Please use the Main Menu> Window> Project Assets, Manager… to check your scene.

If that gives you no useable results, I would like to see the file.

I have sent you an upload link. If possible, I need only one object that shows that behavior.

Please save that scene as “Save Project with Assets… ,” so I get all I need.

I will have a look into it instantly.

Cheers

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Posted: 20 November 2019 05:29 PM   [ Ignore ]   [ # 2 ]  
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Thanks for the files, mford610, very helpful.

All Phong Tags are not fully enabled. If enabled (Angle Limit to on)
I can’t see any problems anymore.
You can select them all at once in the Object Manager, with the filter options.

It works the same, R20 or R21.

Let me know if I missed something.

My best wishes for your project.

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Dr. Sassi V. Sassmannshausen Ph.D.
Cinema 4D Mentor since 2004

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Posted: 20 November 2019 06:54 PM   [ Ignore ]   [ # 3 ]  
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I knew it!!! A single missing checkbox brings down the whole farm - when you don’t know what you’re doing :(

I suspect the problem originated when I imported a CAD file as the base mesh. I used Rhino to export from the native format to STEP and then into Cinema. At no point in that transformation was I aware of a Phong setting option. It may have been there, but I didn’t notice it. I will now!

So what is it about the Symmetry object that generated the defect? It looked and rendered normally before I moved it over.

Thanks - Dr. Wizard!

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Posted: 20 November 2019 07:00 PM   [ Ignore ]   [ # 4 ]  
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Mford610,

I was just working on a reply when I saw your next post. So, I have quickly an answer here, even it took me a while to simulate that problem.
You wrote in your post about everything going black. With the file I got, based on the few elements in it, I tried to recreate the problem. I do not know what happens to your file along the way, but this seems to recreate the effect.

I hope the Normals of the vertices are visible in the screen capture. Can you see the three states they have? When they seem to be “zeroed out”, the object goes black.
https://www.amazon.com/clouddrive/share/7PC6tfOkcUHnlDPqOjqHbZOrhxCyQOaD2N4JxivKXZd
I have no data on this, but I assume that the Symmetry object is not causing it; it just seems to ignore the Normal Tag.

Cheers

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Dr. Sassi V. Sassmannshausen Ph.D.
Cinema 4D Mentor since 2004

Photography For C4D Artists: 200 Free Tutorials. Texture, Panorama, HDRI, Camera Projection, etc.
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Posted: 20 November 2019 07:10 PM   [ Ignore ]   [ # 5 ]  
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Yes, you reproduced the problem exactly. It’s a little baffling, but you’ve highlighted some fundamental principles. Hope I remember them in the clutch :(

I am much more comfortable with modeling than with texturing. I have sometimes set the phong to 5 or less in low-poly models to accentuate their angularity. So I’ve never bumped into this before.

Thanks for the speedy response. I’m breathing again smile

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Posted: 20 November 2019 07:16 PM   [ Ignore ]   [ # 6 ]  
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I’m happy that we could solve that mystery.

Yes, there is a lot of power in the Phong tag. (In a nutshell:) For everyone reading along, it determines the smoothness, or if it shows up as an edge, based on the angle difference of the Normal directions.

Please select the Normal Tag and go to the Structure Manager> Normal, you can see the entries for each vertices that build a Polygon.

If you run into something else, please just let me know, I’m happy to look into it.

Another way to set all Normals of Vertices to zero, and thus render them useless, is a single click of the Use Fields option inside of the Normal Tag.

My best wishes.

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Dr. Sassi V. Sassmannshausen Ph.D.
Cinema 4D Mentor since 2004

Photography For C4D Artists: 200 Free Tutorials. Texture, Panorama, HDRI, Camera Projection, etc.
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