triangle count

[marya]

Hello all,

Where abouts in Maya 3.0 is the information regarding triangle count for a scene? I'm not talking about the HUD - that only displays verts, edges, faces and UVs......I want to know how many TRIANLGES are in my scene.

Can anyone help?

Thanks
[)33p4|2i3d

".....why cant we just keep using softimage|3d?!"

[gmask]

What's wrong with the HUD|Poly Count.. facesa are either quads or triangles so if you select a triangulated objects it will tell you how many faces they have? The three columns display how many faces are int he scene, how many faces are in the selected objects and how many faces you have selected

g

[marya]

thanks gmask,
So does that mean I must first triangulate all the objexts in the scene? If my objects are are built of quads, they will tesselate, abitrarily, at render time, right? I want to know how many triangles there are at render time. How do 'gamers' do it?

In response to
"....if you select a triangulated objects it will tell you how many faces they have......"

[gmask]

So does that mean I must first triangulate all the objexts in the scene? If my objects are are built of quads, they will tesselate, abitrarily, at render time, right? I want to know how many triangles there are at render time. How do 'gamers' do it?

Well this is an interesting question.. I think in games you would triangulate the model before sending it to the game engine but I don't know that you have to or not for sure.

If you modles were nurbs you can open the attribute editor for the object and under tesselation turn on display tesselation and it will show you the triangulation and how many faces there will be.

If your modle is quads the tesselation isn't arbitary.. if every face in the mesh is quad then triangulating it will give twice as many faces. If there are some triangles and some quads then only the quads will triangulate thus giving you less than twice as many faces.

g

[marya]

what I meant by arbitrary is that Maya decides, in each quad, to create an edge from whatever point to whatever point it wants.

I would imagine that game engines won't want to do any tesselating. So i guess another question would be.....How do you turn a model that is a combination of polys.quads and trianlges into all triangles? (aside from manually adding edges)

I hope someone from the games industry can shed some light!

[gmask]

what I meant by arbitrary is that Maya decides, in each quad, to create an edge from whatever point to whatever point it wants.

There does seem to be some kind of logic... faces that are adjoined the triangulation goes in the same direction and not by alternating points.. of course in some situation it will have to do the triangulation from the same points.

I'm not really sure why this is a big issue.. can you explain?

I guess you could use the split polygon tool to control the faces that need to go one way or the other for your purposes and then let the Triangulation function take care of the rest. I think if you wanted a more intelligent method you'd have to define those parameters and write a MEL script tp go from face to face and make decisions on where to do the split.

To be honest I have seen several production models for games and there doesn't seem to be any method or logic to how they are triangulated. I've seen ones that are very orderly and others that are messy.. the messy ones where generated from 3D scans and dicing the high res scan into a low res poly mesh.

I would imagine that game engines won't want to do any tesselating. So i guess another question would be.....How do you turn a model that is a combination of polys.quads and triangles into all triangles?

The triangulation tool does this.. if your model has both quad and triangles it converts your quads and leaves the faces that are triangulated alone.

g

[marya]

I'm not really sure why this is a big issue.. can you explain?

Well, I am doing a model test for a game company and have a limit on the triangle count, number of textures and texture size. I am working on it now and want to keep track of how many triangles I am making....especially when I get near the limit. I'm not as familiar with maya as I am with soft.

The triangulation tool does this.. if your model has both quad and triangles it converts your quads and leaves the faces that are triangulated alone.

Ah yes. I just found it! This will help alot!!

Thanks so much for your help gmask! I really appreciate it!! By the way, I checked out your site......cool stuff. It must be fun to work on such a variety of projects.

[ayman]

Hi Marya,

i wish you luck with your model... here is some advice based on the way we approach our own game models...
first of all, the model we export is triangulated automatically during the exporting process, and so it does not matter if there are quads or triangles in it...
If you need to keep progress of your triangle count without triangulating the model (which is how i prefer it), simply run the triangulate function, check the face count, and then press undo : )
As for the tesselation being arbitrary, well i think it depends on how each face was created... anyhow, one of the last stages of optimising the model (once you know it looks good, and is in the right poly-count zone) would be to triangulate, and then use the flip-edge tool to get any crucial edges going the right way if they aren't already, and also the delete edge tool if you need to save more polys (though this requires practice to work well as a ploy reduction tool)...
i hope this helps... let me know if there is anything you'd like explained further...
Ayman

[fuzy]

Hi There!

I always use the vertex count for keeping track of the complexity of my model, since the vertex is the smallest component of a scene. I'll try to explain:

For example: take a cube with six faces (quad) in the same shell (sharing edges) . This gives us 6 faces, 12 edges and 8 vertices. But if the six faces doesn't reside in the same shell (doesn't share edges) they can still be joined in a polygonal object, which gives us 6 faces 24 edges and 24 vertices. This also goes for triangular geomety - we just have 12 faces instead.
So you can have poly objects displaying the same face count (either nsided or tri) but be twice as complex if the faces don't share vertices. The face is actually is the higest level polygon component where the vertice is the lowest and the edge is the middle. So to get the count which describes the actually complexity of the scene you'll have to look at the vertices. That's my opinion.

cheers,

Ivan

[scotta]

If you don't want to triangulate, there is a MEL command - 'polyEvaluate -triangle' - that will return the number of triangles in selected geometry. There is a script on this site called 'countTriangles.mel' that uses this command to return the total scene triangles without triangulating. This may be a good one to set up as a hotkey or shelf button.

[ayman]

that's great!!!!
one for my shelf, methinks : )

thanks,
Ayman

[pimk]

i understand marya,when she talks about arbitrary tesellation is about the gouraud effect wich is very important,well i still havent found how to flip the diagonal edge of a plane wich can make good gouraud shading look and not artifact stuff.
about the faces count if you want to know how much triangles you have multiply per two the number of faces maya shows in the ui

[joojaa]

pmk not necceserily it might contain triangles too (smooth edge etc...) so be carefum maya actualy uses polys instead of triangles.