Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Bug Reporting => Topic started by: hassanjaber on 2021-08-31, 18:09:51

Title: Physical Material Error - & corona converter
Post by: hassanjaber on 2021-08-31, 18:09:51
Hello most of the time when im converting materials from vray, metal is ticked on, and it's not accurate like it used to be.

+ is there any way we can convert to legacy material instead of physical material, legacy is much more efficient and easy to use when converting to physical I'm losing many of the material properties? any solution
Title: Re: Physical Material Error - & corona converter
Post by: TomG on 2021-08-31, 18:38:47
Examples of the materials that you feel don't convert correctly would be very helpful - preferably in a scene file but screengrabs of the material UI would do in a pinch, with renders showing the Legacy and Physical results. Thanks!
Title: Re: Physical Material Error - & corona converter
Post by: miskokral on 2021-09-10, 15:34:46
Hello most of the time when im converting materials from vray, metal is ticked on, and it's not accurate like it used to be.

+ is there any way we can convert to legacy material instead of physical material, legacy is much more efficient and easy to use when converting to physical I'm losing many of the material properties? any solution

I am experiencing the same problem with Corona 7 and the new Physical Material. I guess that New Corona 7 works that if a material has more than 3.0 IOR in that case it converts that material to metal.
But there is a huge problem here because there is an enormous library of 3d assets that have been done either in previous corona versions or vray with weird numbers and the end result when converting the materials with Corona 7 will create such a big mess. Leaves and grass and fabrics will be turned into metals with weird reflections and imagine all of this when you are working on a huge project with hundreds of materials.
I am asking have you thought of this problem? Do you have any sustainable solution for this issue with the new converter?


Title: Re: Physical Material Error - & corona converter
Post by: Avi on 2021-09-17, 19:53:21
Hi,

It would not be possible to convert materials to legacy mtl and there will also be no such feature in the future also.

But if you have a material that has IOR with a value of 3 or more, they will be automatically converted to metals. In case, you want to change metals to non-metals then you can use this simple script to batch change material type from metal to non-metals.

PS: You should not run this script in your whole 3ds Max project otherwise the materials which should be metal will also be converted into non-metals. To use this script, simply select the offending materials which are supposed to be non-metals in a separate file then run this script and after that, you can merge those 3D objects with correct material properties with your original scene.

I understand many people might have problem with this approach but this is the best workaround currently to fix your wrong metal materials. We are continuously working on improving the converter with upcoming releases.

Regards,
Avi

Title: Re: Physical Material Error - & corona converter
Post by: Deckard on 2021-09-27, 10:38:08
I have the same issue with the current material converter, which mis-understands the metalness on some materials.
The script provides a workaround, but I think there should be an option at the converter to override metalness on demand.
Title: Re: Physical Material Error - & corona converter
Post by: GeorgeK on 2021-09-27, 12:46:34
I have the same issue with the current material converter, which mis-understands the metalness on some materials.
The script provides a workaround, but I think there should be an option at the converter to override metalness on demand.

Thanks for the feedback, we have various improvements logged for consideration.

(Report ID=CRMAX-941)

Title: Re: Physical Material Error - & corona converter
Post by: Erik1974 on 2022-01-10, 09:57:01
I found this thread since i am experiencing the same problems. Only almost all of my materials get turned into metal? Attached is  a very simple object with a material with only a diffuse map on it, the Corona converter makes it a metal material!
Title: Re: Physical Material Error - & corona converter
Post by: Erik1974 on 2022-02-15, 08:01:41
Any update or feedback on this issue? The converter is completely useless like this. Attached is a screenshot of the material editor of a terrain that i converted from Vray to Corona. Almost all the materials turned to metal! There are no metal materials in this scene. Apparently a fallof map in the reflection slot also makes a material metal. But als the grass material got turned into metal, there isn't even a reflection on the original material. Can you please fix this, in a scene with mixed metal and non metal materials it is very time consuming to fix everything by hand since the script to turn metal to non metal is useless in such a situation.
Title: Re: Physical Material Error - & corona converter
Post by: GeorgeK on 2022-02-18, 07:40:40
Any update or feedback on this issue? The converter is completely useless like this. Attached is a screenshot of the material editor of a terrain that i converted from Vray to Corona. Almost all the materials turned to metal! There are no metal materials in this scene. Apparently a fallof map in the reflection slot also makes a material metal. But als the grass material got turned into metal, there isn't even a reflection on the original material. Can you please fix this, in a scene with mixed metal and non metal materials it is very time consuming to fix everything by hand since the script to turn metal to non metal is useless in such a situation.

Hi, there are many upcoming improvements planned regarding the updated Corona Converter, please stay posted for any further news.
Title: Re: Physical Material Error - & corona converter
Post by: Erik1974 on 2022-02-18, 07:44:40
Thank you for letting us know, let's hope the improvements will come soon! I am very satisfied with this render engine but the converter is currently causing some grief. Keep up the good work!
Title: Re: Physical Material Error - & corona converter
Post by: Erik1974 on 2022-05-10, 08:15:55
The converter still doesn't work in Corona 8, the most simple of materials still get converted to metal :(
Title: Re: Physical Material Error - & corona converter
Post by: GeorgeK on 2022-05-10, 09:00:05
The converter still doesn't work in Corona 8, the most simple of materials still get converted to metal :(

Hi, there is a Metalness switch now, right above the convert button of the Corona converter window, if you set it to "Force non-metal" it doesn't help?
Title: Re: Physical Material Error - & corona converter
Post by: Erik1974 on 2022-05-10, 09:07:00
I didn't see the switch but it doesn't work, i just tested. I attached the scene so you can test it (no models in the scene, only materials, max 2015).
Title: Re: Physical Material Error - & corona converter
Post by: Erik1974 on 2022-05-20, 14:20:49
I just noticed something that has to do with this issue. In Chaos Cosmos there are models that also have metal materials where there shouldn't be any.

For example, import 'Vase Flowers 63-21' you will see that almost all materials are metal! I would expect that these models would be checked before publishing?

I really like the addition of Chaos Cosmos but i think this needs to be checked and fixed, i noticed it before with 'Vase 006' too.
Title: Re: Physical Material Error - & corona converter
Post by: GeorgeK on 2022-05-24, 11:30:00
I just noticed something that has to do with this issue. In Chaos Cosmos there are models that also have metal materials where there shouldn't be any.

For example, import 'Vase Flowers 63-21' you will see that almost all materials are metal! I would expect that these models would be checked before publishing?

I really like the addition of Chaos Cosmos but i think this needs to be checked and fixed, i noticed it before with 'Vase 006' too.

Thank you for reporting this.

(Report ID=CRMAX-1626)
Title: Re: Physical Material Error - & corona converter
Post by: DPS on 2022-05-25, 08:44:44
I'll keep an eye on this.
Title: Re: Physical Material Error - & corona converter
Post by: Erik1974 on 2022-06-29, 10:35:50
Just to let you know that in the hotfix this problem still exists...:(
Title: Re: Physical Material Error - & corona converter
Post by: zivallh on 2022-08-09, 01:50:08
I found a solution for this issue which I am facing too, you have to open the scene that you want to convert and use the old "corona converter 1.45"
it will convert it to "corona legacy MTL" without any headache.

Here is the link https://mega.nz/file/qWp1wS4J#z0t-3wXrNS6zvNv2YJV4R0Em3JO9ICKV5FzO_454PMY

A company like this gives new features and doesn't know how to solve problems!


Title: Re: Physical Material Error - & corona converter
Post by: rowmanns on 2022-09-07, 14:46:51
I just noticed something that has to do with this issue. In Chaos Cosmos there are models that also have metal materials where there shouldn't be any.

For example, import 'Vase Flowers 63-21' you will see that almost all materials are metal! I would expect that these models would be checked before publishing?

I really like the addition of Chaos Cosmos but i think this needs to be checked and fixed, i noticed it before with 'Vase 006' too.
Hi,

This issue is now fixed. You can try it out in the latest v9 daily build, you can find it here: https://forum.corona-renderer.com/index.php?topic=36810.msg203090#msg203090

Cheers,

Rowan