Author Topic: Corona 8 Daily Build - Glosiness / Reflection visibility problem  (Read 1128 times)

2022-01-19, 17:27:27

Dionysios.TS

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Hi Corona team!

Today I've found out a big and serious defect which is related to the Glossines and the reflection/refraction visibility of the objects.
To replicate this please use the latest January Daily Buld and do the following steps:

- Create a white plane and put a reflection with glossiness 0.5
- Create a red teapot and put a reflection with glossiness 0.5
- Create a blue teapot and put a reflection with glossiness 0.5
- Create a Corona daylight system and render to see the result.

FIRST APPROACH: Now, right click on the red teapot and under the object properties turn off the "Visible to Reflection / Refraction".
PROBLEM: Render and you should see the glossiness of the other objects wrong!

SECOND APPROACH: Turn on the previous "Visible to Reflection / Refraction" but instead of that go the red material and bring Opacity to ZERO.
PROBLEM: Render and you should see the glossiness of the other objects wrong!

I've tried with one of the October's build 12/10/2021 and is happening as well while the build August 10/08/2021 works perfectly fine!

Let me know if you can replicate this problem.

Thanks,

Dionysios -


RPBW Responsable d’Imagerie / CGI Manager
& freelance 3D Artist.

2022-01-20, 08:40:43
Reply #1

GeorgeK

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Hi Corona team!

Today I've found out a big and serious defect which is related to the Glossines and the reflection/refraction visibility of the objects.
To replicate this please use the latest January Daily Buld and do the following steps:

- Create a white plane and put a reflection with glossiness 0.5
- Create a red teapot and put a reflection with glossiness 0.5
- Create a blue teapot and put a reflection with glossiness 0.5
- Create a Corona daylight system and render to see the result.

FIRST APPROACH: Now, right click on the red teapot and under the object properties turn off the "Visible to Reflection / Refraction".
PROBLEM: Render and you should see the glossiness of the other objects wrong!

SECOND APPROACH: Turn on the previous "Visible to Reflection / Refraction" but instead of that go the red material and bring Opacity to ZERO.
PROBLEM: Render and you should see the glossiness of the other objects wrong!

I've tried with one of the October's build 12/10/2021 and is happening as well while the build August 10/08/2021 works perfectly fine!

Let me know if you can replicate this problem.

Thanks,

Dionysios -

Hi Dionysios, I can't seem to replicate this can you send me a simple repro-scene?
George Karampelas | chaos-corona.com
Chaos Corona QA Specialist | contact us

2022-01-20, 15:09:40
Reply #2

Dionysios.TS

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Hi Corona team!

Today I've found out a big and serious defect which is related to the Glossines and the reflection/refraction visibility of the objects.
To replicate this please use the latest January Daily Buld and do the following steps:

- Create a white plane and put a reflection with glossiness 0.5
- Create a red teapot and put a reflection with glossiness 0.5
- Create a blue teapot and put a reflection with glossiness 0.5
- Create a Corona daylight system and render to see the result.

FIRST APPROACH: Now, right click on the red teapot and under the object properties turn off the "Visible to Reflection / Refraction".
PROBLEM: Render and you should see the glossiness of the other objects wrong!

SECOND APPROACH: Turn on the previous "Visible to Reflection / Refraction" but instead of that go the red material and bring Opacity to ZERO.
PROBLEM: Render and you should see the glossiness of the other objects wrong!

I've tried with one of the October's build 12/10/2021 and is happening as well while the build August 10/08/2021 works perfectly fine!

Let me know if you can replicate this problem.

Thanks,

Dionysios -

Hi Dionysios, I can't seem to replicate this can you send me a simple repro-scene?

Hi George, I need to finish some things and reinstall the latest build and send you a sample file. Yesterday I was having this issue for all the morning without being able to find a solution at all! I'll try again later today and I'll be back to you.

Thanks for your patience.
RPBW Responsable d’Imagerie / CGI Manager
& freelance 3D Artist.

2022-01-20, 17:16:14
Reply #3

Dionysios.TS

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Hi again George,

I replicated the problem in a simpler scene trying to include the basic shaders which are present in the very big one where I initially yesterday found out the problem.
The difference now is that we have a shadow catcher material and the issue is replicated ONLY if we turn off the "Visible to Reflection / Refraction" option on the object who has that material.

- Load the scene and select the object SELECT ME
- Render and look at the result
- Now go the object's properties and turn off the option "Visible to Reflection / Refraction"
- You'll noticed the reflections on the 2 coloured teapots that are not the same but are altered! The red one seems also a bit mettalic!

Is this a normal behaviour? If we don't want the Shadow Catcher objects being reflected in the scene, is not possible or something is wrong?
A last thing, yesterday I am 200% sure that the problem was present also as I described on my first post but not I can't replicate it either, I am sorry!

Thanks,

Dionysios -
RPBW Responsable d’Imagerie / CGI Manager
& freelance 3D Artist.

2022-01-21, 07:58:42
Reply #4

GeorgeK

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Hi and thanks for sharing the file, I am afraid this is an expected limitation regarding light transport issues/black highlights, you can read more about it here: https://support.corona-renderer.com/hc/en-us/articles/4402699661585-Known-bugs-and-limitations

Roughness/glossiness plays a big role in this, as well as certain camera angles can make this effect more prominent. As for the initially reported issue, please note that even if an object is set to be invisible in reflections/refractions its shadows/bounces can still affect neighboring objects so this is why you've might have witnessed red color bleed on your blue teapot's rough-reflection.
George Karampelas | chaos-corona.com
Chaos Corona QA Specialist | contact us

2022-01-21, 10:09:13
Reply #5

Dionysios.TS

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Thank you George,

what confuses me a lot now, is that in a specific big production scene where this should be reproduced as is part of the known bugs / problems it doesn't occur when I use only the 2021_08_10 Daily Build! So I thought was a bug and not intended as in reality is.

Anyway, excuse me for the false alarm!

Dionysios -

RPBW Responsable d’Imagerie / CGI Manager
& freelance 3D Artist.

2022-01-21, 10:38:46
Reply #6

GeorgeK

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Thank you George,

what confuses me a lot now, is that in a specific big production scene where this should be reproduced as is part of the known bugs / problems it doesn't occur when I use only the 2021_08_10 Daily Build! So I thought was a bug and not intended as in reality is.

Anyway, excuse me for the false alarm!

Dionysios -

Hmm, it should be the same all across versions, could it be that some parameter was different? Feel free to share with me to investigate further.
George Karampelas | chaos-corona.com
Chaos Corona QA Specialist | contact us

2022-01-21, 11:30:36
Reply #7

Frood

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- Load the scene and select the object SELECT ME

Side note (not related to your issue and sorry for the broken record):

The scene has 9740 animation layers. Use a cleaner script (or this tiny one as a startup script) to get rid of them, they may cause slowdowns, large scene files and other issues.


Good Luck



Never underestimate the power of a well placed level one spell.

2022-01-21, 15:40:43
Reply #8

Dionysios.TS

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- Load the scene and select the object SELECT ME

Side note (not related to your issue and sorry for the broken record):

The scene has 9740 animation layers. Use a cleaner script (or this tiny one as a startup script) to get rid of them, they may cause slowdowns, large scene files and other issues.


Good Luck

Oh, thanks! Very kind of you!!!
I didn't even controlled the animation layers, 9740 are quite a lot.

Thanks again and take care.
RPBW Responsable d’Imagerie / CGI Manager
& freelance 3D Artist.

2022-01-21, 15:50:00
Reply #9

Dionysios.TS

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Thank you George,

what confuses me a lot now, is that in a specific big production scene where this should be reproduced as is part of the known bugs / problems it doesn't occur when I use only the 2021_08_10 Daily Build! So I thought was a bug and not intended as in reality is.

Anyway, excuse me for the false alarm!

Dionysios -



Hmm, it should be the same all across versions, could it be that some parameter was different? Feel free to share with me to investigate further.

Hi again George,

the file is 7GB big so I've uploaded it in your official DropBox space you have for big files.

Once you'll open the file, select the very big volumes on the right, in their properties their Visible to Reflection / Refraction option is off and it renders good on Daily Build 2021/08/10.
All the other and later Daily Builds, they present the known bug/limitation.

Attention, the file is big and it contains a lot of textures, I am sorry for this!!!

Dionysios -
« Last Edit: 2022-01-25, 10:46:04 by Dionysios.TS »
RPBW Responsable d’Imagerie / CGI Manager
& freelance 3D Artist.