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View Full Version : head gets ripped apart when going to subpatch mode



agentboolen
06-16-2004, 09:31 AM
Hi guys, im trying to model a characters head. This is the first head i have ever done in Lightwave, i have only done characters in 3ds max before. The big problem im having is that i cant seem to get the head smooth. I have tried turning the mesh to subpatch(tab) and im left with all kinds of holes. The faces seem to all have 3 to 4 vertices from what i have seen, but the model just gets rip apart when i go to subpatch mode. If anyone has any suggestions or can tell me what im doing wrong. You can download the file to get a better look, and tell me what im doing wrong. Any help would be very appreciate.

Thanks
Frank :eek:

bloontz
06-16-2004, 09:53 AM
If you look at the polygon statistics panel you will see that you have some >4 point polys and 2 point polys as well as a number of non-planer polys. It also seems that some of your polys may not be connected, try merging points. I haven't used Max but I assume lightwave is less forgiving with subdivision sufaces?

agentboolen
06-16-2004, 10:09 AM
Originally posted by bloontz
If you look at the polygon statistics panel you will see that you have some >4 point polys and 2 point polys as well as a number of non-planer polys. It also seems that some of your polys may not be connected, try merging points. I haven't used Max but I assume lightwave is less forgiving with subdivision sufaces?

Ha, thanks for the reply. Well i think 3ds max makes it easier to extrude. It doesn't leave any faces left in the spot from where you extrude. I think thats whats messing me up. I did the merging points which help my model out a lot but there are still some spots that aren't right. Do you or anyone else have any suggestions for getting the 4 point polys(doesnt it say you can have 3 or 4 vertice polys, would 4 point polys be o.k.?), 2 point polys, and the non-planer polys fixed. Thanks for helping me out so far. If you want to download the merge file its here.

thanks
Frank

bloontz
06-16-2004, 11:01 AM
For characters and other objects that will be deformed it's generally best to design the mesh with 4 point polys, though you can also use 3 pointers for subdivision surfaces but they may not deform as well. Some tools are better at maintaining quads, I use the smooth shift tool mostly I guess.

To fix your mesh you can go in and manually divide the offending polys or just use the triple command on them. Depending on wether you plan on animating or not that could cause some less desirable deformations. You can use the statistics panel to quickly select the offending polys.

I've played with your mesh a bit and there may be some other problems like polys with there normals facing the wrong direction. You can fix those with the flip command (f key). I'll try to look at it some more later on.

bloontz
06-16-2004, 11:32 AM
I had another look at your mesh and you have a number of places where the mesh is discontinuous, that is causing much of the problems. You can't have situations like you have for instance on the cheeks just in front of the sideburns where one edge of a quad is butted against two quads which is leaving a point dangling when you hit the tab key. You would need to make a cut through the band of polyaround the front of the face and through the tip of the nose so that you have only points that connect four quads each in that area.

Hope that makes sense.

agentboolen
06-16-2004, 12:13 PM
thanks bloonts yea i think i understand right now im square out the faces that are messed up. Its starting to take shape. I think 3ds max let me cheat a little more then this program. haha

Thanks everyone
Frank

toby
06-16-2004, 07:11 PM
As bloontz mentioned, you want to use Smooth Shift (shift"F") instead of Extrude for operations like this. It leaves no polys behind nor does it flip them. It extrudes in the direction of the normals, or average of multple polygons' normals. If you don't want that, just click once with smooth shift then hit 't' and drag where you want it to go.

Until you get used to sub-patch modeling it's a good idea to stay/work in sub-patch mode, don't switch back and forth. When you use the knife tool for example, you get a real-time preview of the cut, you'll see if it's causing problems.

Another indespensble sub-patch tool is Bandsaw Pro, it cuts in a loop to maintain continuous 4 pt polygons.