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View Full Version : Subpatch pinching on cartoon character



euge04
07-21-2004, 07:29 AM
Hello I am creating a cartoon character for the first time and I have some pinching going on in the hand of the model. Can this be fixed? Any advice would be greatly appreciated.

euge04
07-21-2004, 07:30 AM
Wireframe

euge04
07-21-2004, 07:50 AM
Forgot this

ginhan
07-21-2004, 12:53 PM
try using skin quads (under mulitply? tab)
I think it's ctrl + K ?

I'd show you which polygons to select, but how do you attach images?

select the 2 polygons that has the "dent" and do spin quads
then select the other 2 below the ones you did to spin them.

that might help
or it might move the "dent" to another location.

tudor
07-21-2004, 12:59 PM
I don't think that spin quad will work there.

It seems that you have left over polygon in the thumb/finger region from an extrude or weld operation. Try to find that faulty poly and delete it.

glassefx
07-21-2004, 01:16 PM
Actually what is happening is usefull sometimes... Whats happened is that you have a polygon under that quad which is also an identical quad but its vertexs are not merged.


Try a merge points and then a unify polygons...

If this does not work select a point on that "troubled-quad" and it should say 2 instead of one (if you select one corner). try a merge at a fixed distance that is small enough not to merge everything you dont want merged...

hrgiger
07-21-2004, 03:08 PM
It looks to me like you just have a point or two unwelded. Go to full wireframe mode and try to lasso each point in that area and see if there are two points or only one. If there's more then one point at each junction, weld em back together.

euge04
07-21-2004, 06:38 PM
Merging points didn't do anything. Unifying polygons made it worse. Merging points that were close seemed to help but it messed up some points that were fine. So I went threw and welded some myself and fliped some quads around and its starting to look better. But I still have pinching where the fingers meet the hands. I guess this is happening because six quads are attached to these points? Is there anything I can do to fix this?

Mipmap
07-21-2004, 11:22 PM
One thing to keep in mind is that some creases that may show up in Subpatch mode will go away completely when the model is frozen for each frame in layout. So you can try freezing your model in Modeler to see if this is the case, and then just clicking Undo after you have done that.

glassefx
07-22-2004, 07:04 AM
Also tri's pull alot, especially when they are surrounded (sharing vertices) by quads... Thats why if you do have to use a tri, try to place it in a inconspicuous location or on a relatively flat, or simple area...

euge04
07-22-2004, 07:29 AM
So some pinching might be acceptable? How can I avoid these problems in the future? How could I have modeled this better? I followed the steps on the Desktop Video training DVD. I created a finger and duplicated them all then welded the ends of the fingers together then smooth shifted the hand out into the arm.

Thanks for all the advice everyone. Its very helpfull.

glassefx
07-22-2004, 07:46 AM
Yeah its fine, I'd maybe like to see a wire/shaded shot of it. Like Mip said though, lots of this pinching will disapear when you freeze the object... I've also noticed when I render a patched object that is NOT frozen in layout that lots of the pinching seems to go away also... What is your patch level set to? this will help also but I like to stay below 4 which means for every polygon, 4 will be made from it...

euge04
07-22-2004, 07:41 PM
Here is the frozen shaded version.

euge04
07-22-2004, 07:44 PM
Here is the shot before freezing. So I see that freezing the object it really makes those six polygons that join at that point very small so their influence becomes very negligible. Why is it better to freeze an object and then bring it into layout? How is this different than bringing the subpatched object into layout? Doesn't subpatching the object merely break it down into smaller polygons during rendering anyway?

Thanks for all the help. Slowly but surely I will learn Lightwave through and through.

crusaderx
08-03-2004, 12:45 AM
my simple answer is ...
look at your hand closely.

you need more geometry in the middle of the fingers...

I'll do some text art here to explain...


yourthe gap between the finger in your model are like:

\/

when the gap on a real hand is more like:

\_/

introduce one polygon width gap between fingers...
think of the subpatch mesh like a spline curve.
so essentially you only have 2 points of pull to draw a curve...

well anyways i dont have the words to explain so i'll attach a quick doodle i did to help you understand what i mean...

hope this helps,
Daniel

glassefx
08-03-2004, 06:52 AM
Originally posted by euge04
Why is it better to freeze an object and then bring it into layout? How is this different than bringing the subpatched object into layout? Doesn't subpatching the object merely break it down into smaller polygons during rendering anyway?

Thanks for all the help. Slowly but surely I will learn Lightwave through and through.

Well, their are advantages and disadvantages to both methods.

Firstly, when one does NOT freeze sub-patches before loading them into layout - LW will treat the mesh like a nurbs surface meaning that everytime a bone deforms the mesh or the mesh changes, it is "re-calculated" so you'll possible have less pinching and such... When you freeze your working with a pure polygon mesh which is fine also, but you cant change the density nor do you have the benefit of the mesh being re-calculuated every time it is deformed.

You could freeze your sub-patches at a super high level, say 10 and then it will be dense enough for bones/deformations but then your pushing a million polygons through your bus.

I learnt to use straight polygons first because they were what I was familar with since I started with Truespace but I hardly ever use them unless I am making certain objects. Here is one benefit to sub-patches.... You'll have to model in edge details to catch light properly and sub-patches have nice edges that do this pretty much automatically. Model a box with straight polys and then use this mesh to make a sub-patch version (you may want to make slices to make it look like a box rather than a sqaurish blob) and the compare them in modeler... See which one is more visually interesting... The sub-patched version is all busy glinting while Mr. Poly will require massaging.

MY 2 Cents.

peace.

crusaderx
08-03-2004, 07:30 AM
There is definately no arguement that subpatches are the best.
not to mention in LW [8] you can have the
subpatch level vary depending on distance from camera....
so automatic detail enhancement or simplification depending on distance... a great render/detail optimization!

euge04
08-03-2004, 12:35 PM
Makes sense to me. Thanks!