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somekindofdevil
08-11-2010, 06:20 AM
Hi;
I'm a little confused about t-vertices. As i understand, they causes shading problems but in the end i have to use them. So when we should use them, when we shouldn't?

Teloni
08-11-2010, 12:15 PM
You referring to poles?
http://www.subdivisionmodeling.com/forums/showthread.php?t=907

somekindofdevil
08-12-2010, 04:39 AM
I'm working on low-poly modeling for games and I'm experiencing shading problems like this;

http://www.cgl.uwaterloo.ca/~smann/Talks/CSC.98.02.18/f18.html

My model has no overlapping faces or vertices but it has some t-vertices. I'm using 3ds Max and Editable Poly. 3ds Max's Smooth modifier solves my problems but as far as I know Smooth modifier doesn't change any transformation data. So am I doing something wrong while modeling?

CGmascot
08-12-2010, 11:28 AM
Somekindofdevil,

You don't have to use those T-verticles, in fact you shouldn't. What you have there is a 5-sided polygon, in other words a N-gon. Every polygon above 4-sided is regarded as N-gon. Instead of that either add one edge in there to change it to a triangle and a quad so that the edgeflow continues instead of abruptly stopping, or change the geometry more to keep all quads.

Do note that when you model for games, like you do now, all polygons get triangulated when exported to game engine - everything becomes triangles anyway. If you leave N-gons in the mesh, they may get divided in a way that you won't like at all. It is better to make that 5-side into a quad & triangle instead.

Also note that since everything becomes triangles anyway in game, you could make them already triangles yourself. Then with every trangle you have one more edge to define the shape with. This is handy and a way to keep polycount low. See my Low-poly Tips (http://www.cgmascot.com/design/low-poly-tips/) for explanation with pictures.

Of course if you make all triangles yourself, the mesh will look confusing - it will be harder to see if general polygons flows are good or not. So use the above trick with reason.

I understand this Smooth-modifier you talk about smooths the look of the mesh in 3DS Max but doesn't subdivide it. Then the Smooth only affects the shading properties. Do note that while games use smoothing as well, it may not work the exact same way as the smooth in 3DS Max and your N-gon may result in shading artifacts anyway. Actually likely will look odd anyway, because it gets triangulated in a way that you are not controlling.

Did this help? Ask more if needed.

- Niko

somekindofdevil
08-12-2010, 09:23 PM
It was really helpful. Thank you very much.

CGmascot
08-13-2010, 06:36 AM
No problem. I'm glad I could help a bit.

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