Chaos Corona Forum

Chaos Corona for Cinema 4D => [C4D] Bug Reporting => Topic started by: Matthew86 on 2022-12-11, 11:39:01

Title: Using plane with light material as background
Post by: Matthew86 on 2022-12-11, 11:39:01
Good morning,
I'm experiencing this issue while using a plane with a light material applied to use as background image. As you can see from the images attached when the reflection of the sun, or the hdri aswell, is in corrispondence of the plan reflection it is converted into a shadow. I don't know if it is a known bug or if there is a solution.
Title: Re: Using plane with light material as background
Post by: Beanzvision on 2022-12-12, 14:06:46
Hi there, are you able to share your scene with us? I'm not able to reproduce it here. Thanks!

*Update. This is actually a known issue which has been reported before and is mentioned in our helpdesk article here under ''Black Highlights'' here: https://support.chaos.com/hc/en-us/articles/4528311915025-Known-bugs-and-limitations

I hope this helps.
Title: Re: Using plane with light material as background
Post by: Matthew86 on 2022-12-12, 20:12:14
Hi!
Thanks for the advice, I tried this workaround but it is not working very well because the reflection of the plane/background the does not work.
It is the same effect i've achieved turning off the reflection visibility of the single light material of the background.
Title: Re: Using plane with light material as background
Post by: Beanzvision on 2022-12-13, 12:11:12
Hi there, are you able to send us your scene so we can check it?
Title: Re: Using plane with light material as background
Post by: Matthew86 on 2022-12-13, 12:53:22
Hi there, are you able to send us your scene so we can check it?
Hi, yes of course. Please find attached it below.
Title: Re: Using plane with light material as background
Post by: bnji on 2023-05-08, 06:58:46
Hi there,
Thanks for bringing our attention to this.
This has already been reported to the devs team.
(Internal ID=1109790354)

Title: Re: Using plane with light material as background
Post by: Matthew86 on 2023-09-15, 19:14:22
Hi Bnji,
I know the post is very old, but I wanted to know if there have been any developments regarding this bug. As of today, it still seems to be present, and I can't figure out how to resolve it. Every time I need to set a background that should be reflected by the project's materials, the lighting is completely ruined by this issue
Title: Re: Using plane with light material as background
Post by: Matthew86 on 2023-10-10, 00:07:52
Could someone reply please?
Title: Re: Using plane with light material as background
Post by: bnji on 2023-10-24, 09:16:13
Hi @Matthew86,
Thanks for your reply.
As mentioned before, this was reported to the devs.
They investigated this, but they need to find a different approach for this as there are some limitations regarding how lighting from Corona Sun is being calculated and the workflow you're trying to implement. (and this might take some additional time as it is not some simple fixing as it sounds)
A workaround for this would be...
If you're rendering an interior scene, you can use the "Direct visibility" override in the Render Settings -> Scene environment section to load a background image using a Corona Light material.
You can load the Corona Light material there, set the Mapping mode to "Frontal" and then fine-tune the image's position and scaling using the Offset and Scale parameters.
I hope this helps.
Please let me know the outcome.