Rhino

[Audrey Obelyn]

How many of you are using Rhinoceros 3D? I'm just curious :matte-motes-grin:

[Bhakti Mimulus]

I just downloaded it. I am taking a class at the local JC and it is much cheaper for students

[Krystle Poikolainen]

Such a deafening silence on this topic.

I love Rhino, and I've been trying, and trying, to find a way of uploading a mesh where it is possible to assign different colours and textures to different faces of an object.

Has anyone discovered how to do it ?

[Chic Aeon]

3 minutes ago, Krystle Poikolainen said:

Such a deafening silence on this topic.

I love Rhino, and I've been trying, and trying, to find a way of uploading a mesh where it is possible to assign different colours and textures to different faces of an object.

Has anyone discovered how to do it ?

What you want to find is a way to MAP and add MATERIALS (those are the generic terms). Hopefully Rhino can do that. If not, that would mean exporting the file in something Blender could read and then using Blender (or another 3D program that does this) to finish your item.

The silence is that almost no one uses Rhino for SL.  I don't know WHY but likely it doesn't put out files that work well here. 

 

[Coffee Pancake]

It's been a number of years since I used Rhino .. it's certain a very capable, but perhaps not really suited to real time content, the models it creates can easily be very high poly. 

[Krystle Poikolainen]

Thanks Chic and Coffee.

I hear what you're both saying, but I really want to crack this Rhino thing. The current release (version 6) has all the tools for adding materials and mapping, and I'm just hoping that someone may have figured out the settings that will allow an exported dae file to upload into SL, and maintain the multi-material information.

I've tried going via 3ds Max and applying the multi/sub-object treatment, but after using the FBX file converter the resulting dae file will not upload to SL.

I live in hopes of a solution.

[Chic Aeon]

I went over to the site and looked at the sales materials. I think I may have looked at this in version 1 oh so long ago for RL work.  Two things popped out.

This looks like extremely high poly modeling -- that won't import into SL in any usable fashion.

It looks like PBR shading. Now I am not really sure what PBR shading is (I have read about it but that's it) but PBR doesn't work in SL either. 

This seems to be a tool for RENDERS and not GAME ASSET 3D objects.  

Google will perhaps be your best friend there. 

[OptimoMaximo]

Rhinoceros is a NURBS based modeling suite. Therefore the result is going to be converted to a very high polygon model, once imported to another 3d software, which is going to be a problem to import to SL. Your best bet is to try and reduce the imported model in 3dsmax until you get a mesh <65535 vertices, which is the top limit for import in SL

[Chic Aeon]

2 hours ago, OptimoMaximo said:

<65535 vertices, which is the top limit for import in SL

Responding to the OP :

But there are some major issues with meshes over 23,000 ish (someone will know the actual number :D).  So basically it is going to be TOUGH to get the models usable for SL let alone "game asset" low poly models which is what we need here. 

Glad to know our assumptions were on the right track :D. 

[OptimoMaximo]

I have to correct myself here, as the max number of vertices is 256*256 = 65536 per mesh object

The other limit is a material issue, where if a material is being assigned to more than 21844 vertices it gets silently split into a submaterial, which will be missing in the lower LoDs and, therefore, causing the dreaded MAV block missing error 

[Chic Aeon]

From the wiki on a good to remember about page called "limits". Plenty of important stuff their.   

Along with the materials problem, there is also a major physics issues that we discussed in length a year or so ago where the physics model no longer "sticks" to the actual size of the object.  "I" was the one with the issue and worked around it somehow, but mostly I remember just to keep files SMALLER (which of course they should be for oh so many reasons).

User Found Temporary Mesh limits:

Because of an apparent bug in the importer stay within these limits.

• 174,752 triangles, beyond which additional triangles will appear as holes.
• The 64k vertices per material is pre-empted by a limit of 21,844 triangles per material, which is presently reported as BUG-1001. (4/2014 - See discussion page)

 

The import process will continue making new materials beyond 8 x 21,844 (=174,752) triangles, but the extra triangles then get dropped by the limitation to 8 materials, causing holes in the resulting object. Over the 21,844 triangle limit, the vertex count will start to climb steeply, even with smooth shading, because the materials get highly interspersed. So the same vertices have to appear in multiple material lists. So the moral of the story is to stay below 21,844 triangles per material, for now, if you want to avoid some unexpected effects.

Since viewer release 3.8.4, processing of meshes in the Collada file that have faces assigned to more than 8 materials has changed. Instead of simply dropping the extra material faces, the uploader now creates a new object to accommodate them. The result is that the single mesh is divided into multiple objects (prims) in a linkset. Thus the limitation to 8 materials is removed as far as input is concerned, but still applies to each of the resulting linked objects actually uploaded. As a consequence it is now possible to upload a mesh with more than 174,752 triangles, although it will be divided into multiple objects.

[arton Rotaru]

On the discussion page of Limits, it's also mentioned that the 21k limit only applies to Collada files with <polylists>. Which is what Blender used for Collada exports up until to version 2.78. It hasn't been an issue for exports from Autodesks Maya, or 3ds Max since they already exported geometry as <triangles> when the Triangulate option is ticked in the export dialog.

Gaia Clary has modified Blenders Collada exporter in version 2.79 and above, which now also exports geometry in <triangles>, if the Triangulate option is ticked in the export settings, or the mesh contains only triangles anyway.
 

 

[OptimoMaximo]

59 minutes ago, arton Rotaru said:

Triangulate option is ticked in the export dialog.

This option may cause trouble to triangles near strongly bent surfaces (mouth corners for example), rendering affected triangles as holes. In such case, it's advisable to triangulate the objects prior to export rather than upon export in the dedicated dialog.

[Chic Aeon]

5 hours ago, arton Rotaru said:

On the discussion page of Limits, it's also mentioned that the 21k limit only applies to Collada files with <polylists>. Which is what Blender used for Collada exports up until to version 2.78. It hasn't been an issue for exports from Autodesks Maya, or 3ds Max since they already exported geometry as <triangles> when the Triangulate option is ticked in the export dialog.

Gaia Clary has modified Blenders Collada exporter in version 2.79 and above, which now also exports geometry in <triangles>, if the Triangulate option is ticked in the export settings, or the mesh contains only triangles anyway.
 

 

Thanks. Good to know.

 

I had some major problems with 2.79 so still in 2.78.  Will keep that in mind when I try the next release! Really though, even on a house it is "better" to minimize your materials for other reasons *wink*, so I will likely stick to that rule.  I have been uploading whole house (not as linksets) with less than 8 so it certainly can be done with some planning.  

[arton Rotaru]

4 hours ago, OptimoMaximo said:

This option may cause trouble to triangles near strongly bent surfaces (mouth corners for example), rendering affected triangles as holes. In such case, it's advisable to triangulate the objects prior to export rather than upon export in the dedicated dialog.

Well, doing proper triangulation, especially at troublesome areas, is part of the usual workflow anyway. Max has a handy feature where you can flip triangles easily even when the mesh is all quads still. The triangulation on export will keep these edge orientations as well.

However, since pretty much anything I have uploaded since materials has a High to Lowpoly baked normal map, everything is pre-triangulated anyway. Because it's essential to have matching triangulation on the in-game model, and the bake to model.

Edited June 30, 2018 by arton Rotaru

[arton Rotaru]

11 minutes ago, Chic Aeon said:

Thanks. Good to know.

 

I had some major problems with 2.79 so still in 2.78.  Will keep that in mind when I try the next release! Really though, even on a house it is "better" to minimize your materials for other reasons *wink*, so I will likely stick to that rule.  I have been uploading whole house (not as linksets) with less than 8 so it certainly can be done with some planning.  

Yeah right, actually I think I have never uploaded a single mesh which with with that many tris as well.

But if you want to, or need to have that many tris, it's doable even in Blender now, without splitting the tris in multiple materials to workaround the limit, which is a perfomance concern as well.

[OptimoMaximo]

1 hour ago, arton Rotaru said:

Well, doing proper triangulation, especially at troublesome areas, is part of the usual workflow anyway.

That is why i was pointing out that the automatic fbx export triangulation may cause issues.

[Lexbot Sinister]

Rhino does perfectly fine low-poly topology for meshes if you know exactly what you are doing.  There's also features for reducing tri's on a higher poly mesh, and it can be pretty alright as well, with certain types of areas being more troublesome (and certain areas less!)

Building in rhino can be as simple as saying what you want to to, because you can write commands and Rhino will help you along to get where you are going.

My praise part ends there though. It's possible to assign materials, and make some sort of UV mapping too, but i haven't found a way to export to collada yet. There is a collada extension, but it doesn't work (for me at least) to take things to SL. Also the UV mapping doesn't seem to be compatible with anything else, either.

 

So Rhino isn't really a very functional tool for SL, and as far as i know, there are no rigging tools at all. So it can be a part of a work flow, but doesn't cover all areas needed for SL. If i had to pick something similar to Rhino to learn, i'd go with Maya.

[Bitsy Buccaneer]

14 hours ago, arton Rotaru said:

Well, doing proper triangulation, especially at troublesome areas, is part of the usual workflow anyway.

Would someone kindly provide a short explanation of 'proper triangulation'? I just want to make sure I'm doing things as well as I can. I make all my LoDs by hand and don't use decimate or anything like that.

Thanks x

[OptimoMaximo]

1 hour ago, Bitsy Buccaneer said:

Would someone kindly provide a short explanation of 'proper triangulation'? I just want to make sure I'm doing things as well as I can. I make all my LoDs by hand and don't use decimate or anything like that.

Triangulation is something that the softwares do under the hood even when you work with quads. You can notice it when you skew a quad too much, it gets bent and folded in two triangles even if the triangles don't show an actual edge running diagonally through the quad itself. When rigging, there are a few areas that are more densely populated of polygons to allow a smoother deformation, lie eye and mouth corners to name a couple and give you an idea. When you get to test the rig weighting, you may notice that such areas show some bending and deformation that affects the shading, following a quad's triangle which obviously doesn't bend the right way around. That is the moment for using tools like the one Arton had noted, Maya's Flip Triangle Edge and even Blender's got its own, although i don't remember the exact name it has in there. When all has been fixed and looks good, proceed with actual triangulation in the software and don't let it do automatically upon export.

[Chic Aeon]

1 hour ago, OptimoMaximo said:

even Blender's got its own, although i don't remember the exact name it has in there. 

Modifier >Triangulate ?

[arton Rotaru]

3 hours ago, Bitsy Buccaneer said:

Would someone kindly provide a short explanation of 'proper triangulation'?

It's that peak or valley thing on non planar polygons.
This is all the same model, just with different edge orientations at the corners.

[Bitsy Buccaneer]

@arton Rotaru Very cool. And very helpful graphic.

@OptimoMaximo I haven't made anything rigged yet, but you probably just saved me about three days of tearing my hair out when I do.

Between the two of you, I think I understand this well enough to avoid mistakes. Just don't ask me to write an exam question on it

Thank you!

[OptimoMaximo]

6 hours ago, Chic Aeon said:

Modifier >Triangulate ?

It's also vailable in the Mesh menu if i recall correctly, not in form of modifier, along with a quadrangulate option

[Chic Aeon]

3 hours ago, OptimoMaximo said:

It's also vailable in the Mesh menu if i recall correctly, not in form of modifier, along with a quadrangulate option

Well I can't find that MESH menu but don't have need so not a worry. 

I CAN say that if changing EDGE orientations is the same (ish) as changing vertex orientations --- it is NOT easy in Blender (2.78 anyway). For a long while you couldn't change the orientation at all.  Drongle explained in a thread maybe two years ago how to go about doing this. At the time it was WAAAAAY over my head.  I might get it now. 

So score one for the more expensive softwares :D.  If Blender gets finicky and does that nasty triangle thing (happily almost never now) I just start over and the next time it doesn't LOL.   Sometimes NOT fiddling is the best plan timewise.    

 

EDIT:  Apparently what I was thinking about and what was REALLY the method were different --- see latter posts. The changing direction of vertices effects that weird shiny look on one face -- happily I haven't seen this in so long I don't remember too much :D.

Edited July 1, 2018 by Chic Aeon
adding info