Material Attributes in obj-Materials Tweet

[Refracty]

Hi,
I was trying out the Rhino Export Plugin. Really good job Sam!
I have a few questions about the materials that are exported.
As far as I can see the exporter transfers information about diffuse color, glossyness and glossycolor but not transparency and textures but I am not 100 % sure. Will Rhino keep and forward information about Polyobjects as well?
So here is what I assume in terms of material export but please correct and extend this list!

Material:
- diffuse color: yes
- glossyness: yes
- glossy color: yes
- transparency: no
- textures from NurbsSrfcs (transfered into polygons): no
- textures from polyobjects: ?
- ...

other things that are exported

Camera:
-transformation (translation, rotation, up vector,...)
- Render resolution

Misc
- scene scale

Is this information correct?
What would you add?
Thanks
Refracty

[SamPage]

As far as I can see the exporter transfers information about diffuse color, glossyness and glossycolor but not transparency and textures but I am not 100 % sure. Will Rhino keep and forward information about Polyobjects as well?
So here is what I assume in terms of material export but please correct and extend this list!

Material:
- diffuse color: yes
- glossyness: yes
- glossy color: yes
- transparency: no
- textures from NurbsSrfcs (transfered into polygons): no
- textures from polyobjects: ?

Sorry for the delay in responding. Most of the above is correct, expect textures. Textures will export, but there is a bug in which I am not replacing spaces or special characters in material and texture map names, so in some instances they will not export. The path of the texture maps is also written as a relative path, not an absolute path, and is truncated to 8.3, so it is possible for the wrong map to be loaded. There is a lot of work to do in this area, but if the shortcomings mentioned above are not consistent with what you are seeing, please let me know.

Sam

[Refracty]

Hi Sam,
thanks. I have to try out the texturing abilities. That sounds great.
But transparency will not translated in opacity in Octane isn't it?
Ciao
Refracty

[Refracty]

Hi Sam,
happy new year.
I am working on a interior design scene and would like to use octane for the rendering.
I am working on a interior scene where many changes happen and I cant re assign all the materials in octane after the camera position or geometry has been changed.
Is it possible to assign materials like steel (highly reflective but low diffuse) and glass (transparent and reflective) in Rhino (or adjust the obj-mtl file manually)?

If it is not possible I could try to import obj's as instances in Octane and the camera as fbx. Is it possible to export the Rhino cam and import it as fbx cam in Octane?


The only difficulty I see is the flexibility of changes in geometry when materials have been assigned.
Thanks for your help.
Refracty

[Refracty]

Is it possible to autosmooth round geometry in the exporter?

Is it true that there is some kind of Scene Scaling while exporting? I habe adjusted the geometry and imported it into the Octane scene but now it is much smaller.

Hope I don't get on your nerves with these question. I really appreciate your investment of time into the exporter and forum.
Thank you Sam

R

[SamPage]

Happy new year to you as well

About the materials, the one thing to check is that there are no spaces in the Rhino material name. Materials like your steel example (high reflectivity low diffuse) should come in fine. Glass will have issues. Reflectivity should come in no problem, but octane seems to be ignoring the transparency value in the mtl (d = ... ). I notice if I add a index of refraction to the material of something greater than 1, then I get transparency. If you want to try this yourself, add the line "Ni 1.55" (remove the quotes, 1.440 - 1.900 is the IoR of glass) to the material definition for your glass material in your mtl. I'll look at getting this working better when I have a chance.

As for the smothing, this appears to be a bug in Octane. Only the first material in the mesh node comes in with smooth checked. I'll ask about this.

There is scene scaling. The exporter looks to see what units you are modeling in, and will scale the obj to meters. So if you are modeling in feet and have modeled a room that is 12' x 12', it will export to Octane as 3.658 units (meters) x 3.658 units. If you are modeling in meters and your room is 4m x 4m, then it will come into Octane at 4 units x 4 units. Let me know if this is not what you are seeing.

Sam

[Refracty]

Thank you Sam.
I tried to modify the Refraction index in Rhino 5 WIP but it doesn't make the glass transparent. So I think I would have to do it manually like you described.
Good to know about the unit translation of Rhino - Octane.
I hope this transparency issue will work some time.
Cheers
Refracty