View Full Version : Sub patch - trying to learn

02-14-2004, 12:07 PM
Help anyone!

I'm new to sub-patch modeling and am currently builfing a character. In these images, you'll see a rough spot where some polygons come together at one point. The shading stops being smooth at the intersect point. What should I do about this?

(I'll include the cage view in the next post.)

Please help!

02-14-2004, 12:07 PM
Here is another image

02-14-2004, 12:09 PM
I guess the original image didn't make it...

02-14-2004, 04:04 PM
:cool: bad mesh, check for doubled points or polys^^

02-14-2004, 04:24 PM
Hmmm - tried that. No good. Always where multiple ploys connect.

02-14-2004, 05:46 PM
Can't see a shaded wireframe but it looks like you have a 5 poly point. ( ie 5 polys connecting to 1 point.)
If you do then you will have to get it down to 4 or less.

That idea was 99.5 %
this one is the rest

Look for a poly inside model connecting those points.
Just be in poly mode and click on the wireframe lines where the problem is. if there are any then they will show up then.

But I am pretty sure it's the first Idea.

02-14-2004, 06:26 PM
Yes - it is the 5 poly thing. This is more than likely a dumb question, but do you have a good way to fix it?

Probably the answer is really obvious, but it eludes me with all the other stuff in my tiny head.

Thanks for your help, BTW...

02-14-2004, 06:28 PM
Just some general tips first.

1. Bring up the Polygon Statistics window and make sure that you have no two point polygons in the mix. If you do, just select them and delete.

2. Merge Points

3. Unify Polygons

4. Delete any hidden internal Polygons after you perform functions like extrude.

and most likely in your case

5. Do a test render and see if it's creating a problem in the final renderred image. If so you may need to increase the 'Render Resolution' in the Object Properties panel. and/or tweek the position of points in the mesh, maybe adding extra edge loops to relieve tension around the points that are intetersected by 5 or more points.

Also check my modeling tuts below.

jin choung
02-14-2004, 11:33 PM

actually, it looks like you're using quads in weird and unnatural ways... :)

what i mean is that in both cases, it looks like you ran into a situation where you needed a triangular fill but you heard that it's better to use quads so you created a diamond shape to keep it quads.

that's good in some circumstances but it can indeed create pinchy points like dat.

you could try simply triangulating to see what that looks like. if that doesn't solve it, ya gotta reconstruct around those areas so that you really do have a regular quad construction round those areas.

finally, if you're going to FREEZE these geometry into a super dense poly and don't need the model to stand up as an SDS surface, you can try METAFORM to create the final mesh. sometimes, that will create a nice mesh where the TAB sds fails.



02-15-2004, 12:03 AM
but do you have a good way to fix it?

I'd have to see the 'Shaded wireframe' in full view (straight on)

but usually not too hard to fix if you follow thw rows and see if you can get the quads to all come together correctly, by deleting offending poly and rebuilding that section.
Do a screen grab and I will check.

02-15-2004, 10:32 AM
First of all, thank you everyone for your assistance. Here is a front view of my model.

02-15-2004, 11:49 AM
Ok, easy and fast

You have 8 points surrounding mouth?
Grab all polys inside that loop and cut to another layer (that includes lip? too

Now back on original

Take the 3 outside and select them (step 1) and (step2)
Then connect the 4 point ones in center (step3) and (step4)

Now you have 4 polys, highlite them, and 'smoothshift' and
pull into object to start the mouth by pulling in some.
deselect the 2 tri polys on cheeks and 'smoothshift' the quads and make lip as you want.
You now only have 2 polys to work with so will smooth out great on lip.

All will smooth out now when you hit 'TAB'

As for other, it's kinda covered by chin?
but it looks like you can just welt the points where it slpits from tris to quads in center, then remove the 2 point polys., that should smooth out now if I am guessing what it looks like behind the chin.

02-15-2004, 11:51 AM
ARRG..forgot pic:D

02-15-2004, 12:09 PM
Better way

same as before (remove all the polys from the 8 points around mouth)
But this time highlite points in order of pic and make polys (black and green)

Highlite those polys and use 'knife' and cut from 'a to b'

deselect polys and weld the new cut to old object.
now do same as before and highlite those new polys (4) and 'smoothshift' into mouth and lip.
Same amount of polys but no tris:)

02-15-2004, 12:16 PM
Here's ones I am talkin bout.

the blue spots is where I think there are 2 points that can be just welded and remove the 2point polys after.

02-15-2004, 01:03 PM
Do a render to see actually. Don't believe open gl 100%. I've had some open gl spots that went away in the render.

02-15-2004, 02:11 PM
JDaniel is right. Just it is an opengl. Try a render which will looks so fine without creases.

02-15-2004, 02:13 PM
It will show in render if close enough..mine do
Unless it is on a flat or un-animated place.

02-15-2004, 03:28 PM
Again, thanks to all - every suggestion has helped. Yeah, the final render obscures it quite a bit, but I wouldn't call it acceptable to the "perfectionist".

I guess I was looking for a really simple quick fix, but I suppose the whole process of building models requires much trial and error so these things are nipped in the proverbial bud before they happen. So I guess it's back to the tuts and playing with bandsaw, jigsaw et al.

Thanks once again!

02-15-2004, 03:59 PM
Try spinning quads to make the flow better also. :)

02-15-2004, 04:33 PM
It looks like you've got different problems on both left and right sides of the model. If you want to fix this and keep the symmetry I think I'd just delete the right hand side of the model. Use Volume Select to do this. You've got a nice clean seam going straight down the centre, so it would be easy to do.

Then fix up the left hand side. When you're done use 'Set value' to align the centre points to the X Axis and mirror the missing half back into place.

Zafar Iqbal
02-16-2004, 01:49 AM
OMG some amazing drawing skillz! ;)

02-16-2004, 09:18 AM
OMG some amazing drawing skillz

I was eating hotdogs and chips at the time in 1 hand and a coke and the mouse in the other.:D

It was good tho hu?