Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: louisryko on 2018-06-12, 15:31:53

Title: Corona Material scale
Post by: louisryko on 2018-06-12, 15:31:53
Hi All,

As I understand; all Corona materials (from the material library) are set to mm (millimeters). Is this correct?

I always work in MM, however occasionally, and I can't figure out why, how or when, the materials seem to apply at an entirely wrong scale (sometimes cm, sometime m, sometimes even bigger).

Any idea why this is happening? Am I missing something? My workflow is to usually import from Rhino, if that makes any difference. But I always start in mm, and import from Rhino in mm.

I'm new to 3DS Max/Corona, so please excuse potential amateur errors. Any help appreciated! Thanks.
Title: Re: Corona Material scale
Post by: maru on 2018-06-12, 15:44:53
Hi, if you are referring to the new material library in the V2 daily builds, see:
https://forum.corona-renderer.com/index.php?topic=20616.0
Title: Re: Corona Material scale
Post by: PROH on 2018-06-12, 15:50:53
+ another thing. If you like many others scales things on object level in Rhino, then this will give a result like what you describe when imported in Max. If that's the problem, you need to reset X-form on those objects (Utility tab).

Hope it helps
Title: Re: Corona Material scale
Post by: louisryko on 2018-06-13, 16:30:11
Thanks for the replies...

Something weird is definitely going on.

My scale is set to mm. I make a 3000mm x 3000mm x 3000mm box and apply a corona wooden texture to it. It applied perfectly.

When I import a model (from Rhino, also built in mm, and exported at mm, and imported at mm) and apply the exact same material to the imported geometry, the scale is WAY off. I have to decrease the 'real-world scale' by 1000 for it to display correctly. Same goes for imported geometry from Sketchup

The suggestion of trying reset xform hasn't helped.

Any suggestions/tips/hints welcome...Thanks!

Edit: When I apply UVW map modifier to the object, without changing the scale, ie; keeping real-world scale, the texture scale suddenly appears correct.
Title: Re: Corona Material scale
Post by: maru on 2018-06-14, 12:01:02
Could you share a scene with us? With the 3ds max box and the rhino box? It's probably some 3ds max/import/export scale magic.
Title: Re: Corona Material scale
Post by: louisryko on 2018-06-14, 13:26:18
Could you share a scene with us? With the 3ds max box and the rhino box? It's probably some 3ds max/import/export scale magic.

Sure, I've sent you a PM.

Cheers.
Title: Re: Corona Material scale
Post by: louisryko on 2018-07-18, 10:57:29
Could you share a scene with us? With the 3ds max box and the rhino box? It's probably some 3ds max/import/export scale magic.

Hi Maru, did you ever get a chance to look at this?
Title: Re: Corona Material scale
Post by: maru on 2018-07-19, 17:27:36
Sorry, but not yet. I'll try to check it ASAP.
Title: Re: Corona Material scale
Post by: maru on 2018-07-24, 15:09:09
Sorry for the delay.
I checked your model and it seems it has uvw mapping baked in it. This won't work out of the box with RWS mapping, so the solution is to either apply some simple uvw mapping such as box, and enable "real world scale" option, or use the tips from this thread: https://forum.corona-renderer.com/index.php?topic=21108.0

Hope it helps!
Title: Re: Corona Material scale
Post by: Vlad_the_rant on 2018-07-31, 16:21:09
The Corona Material Library is intended to be used in scenes with mm as units and if a material contains the CoronaTriplanar texture map you will need to adjust the scaling of the map to fit (so divide the value by 10 if your scene is in cm).

For objects imported from other software that seem to have the wrong scale, make the object the size you need then apply the XForm modifier then convert the object to an edit poly or edit mesh. This should fix the scale mismatch issues.
Title: Re: Corona Material scale
Post by: maru on 2018-07-31, 16:43:13
The Corona Material Library is intended to be used in scenes with mm as units and if a materials contains the CoronaTriplanar texture map you will need to adjust the scaling of the map to fit (so divide the value by 10 if your scene is in cm).
This is fixed in the Corona 2 material library. :)
Title: Re: Corona Material scale
Post by: Vlad_the_rant on 2018-07-31, 17:24:22
Ah yes, my bad. I was thinking of 1.7's library.
Title: Re: Corona Material scale
Post by: louisryko on 2018-08-15, 08:51:12
Hi Guys,

Thanks for the feedback and the suggestions.

However, resetting xform doesn't seem to help. I previously presumed this was a issue with importing from Rhino, but now I'm working on a file from ArchiCAD (imported as *.obj) and I have the same issue - I import objects, apply a corona preset material and it's scale is 1000 times too big. I have to add 'UVW map' modifier, untick 'real-world size' and input the L,W+H as "0.3" in the case of most of the wooden materials.

Hitting 'reset xform' as you've suggested doesnt help this. Am I missing something?

Any help much appreciated! Thanks...
Title: Re: Corona Material scale
Post by: iancamarillo on 2018-08-15, 18:21:56
are you appling reset xform, collapsing to edible mesh and then applying materials/uvw mod in that order?
Title: Re: Corona Material scale
Post by: louisryko on 2018-08-16, 06:25:33
are you appling reset xform, collapsing to edible mesh and then applying materials/uvw mod in that order?

Yes, definitely...
Title: Re: Corona Material scale
Post by: Jpjapers on 2018-08-16, 13:23:26
are you appling reset xform, collapsing to edible mesh and then applying materials/uvw mod in that order?

Yes, definitely...

I often experience the same issue with revit geometry.
Title: Re: Corona Material scale
Post by: iancamarillo on 2018-08-16, 19:05:26
can you create a box in max, add edit mesh and attach all imported objects. Then see if the materials work as expected
Title: Re: Corona Material scale
Post by: Jpjapers on 2018-08-17, 17:18:59
can you create a box in max, add edit mesh and attach all imported objects. Then see if the materials work as expected

This is how i usually sort it