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Turner
10-23-2004, 09:30 AM
Hi -

I've just begun learning about subpatches... what I'm wondering is if there is a straightforward way to subpatch parts of an object and then "reconnect" them to non-subpatched sections.

Doesn't seem like there's an easy way.

Now, I'm sure something like this is done all the time... how is this handled? Spline patches? Something other than subpatches?

thx
Andrew

xchrisx
10-23-2004, 11:37 AM
to subpatch parts of an object, just use the polygon selection tool, select the polys you want subpatched and press tab (they can still be connected to nonsubpatched polys). If you just want to smooth them without subpatching, just give the polys you want smoothed a different texture and in texture editor check "Smooth".

-chris :)

Turner
10-23-2004, 12:19 PM
Hi Chris -

When I do that, I still get gaps between the "tabbed" polys and the "non-tabbed" polys, as you can see on the right side of this model, which has been tabbed -

http://www.turnerdesign.net/subsurf/subSurfGaps.jpg

thx
Andrew


to subpatch parts of an object, just use the polygon selection tool, select the polys you want subpatched and press tab (they can still be connected to nonsubpatched polys). If you just want to smooth them without subpatching, just give the polys you want smoothed a different texture and in texture editor check "Smooth".

-chris :)

xchrisx
10-23-2004, 01:34 PM
If you are trying to smooth out that portion, I would suggest subdividing the mesh. Then you can apply smoothing to it and it shouldnt effect the rest.

-chris

Turner
10-23-2004, 04:46 PM
No, I'm not trying to smooth out that portion - I'm trying to prevent it from detaching from the adjacent surfaces (if possible)...

I've reloaded the image with a green background to make it a little clearer -

http://www.turnerdesign.net/subsurf/subSurfGaps.jpg

thx,
Andrew


If you are trying to smooth out that portion, I would suggest subdividing the mesh. Then you can apply smoothing to it and it shouldnt effect the rest.

-chris

spud_q
10-23-2004, 05:30 PM
You can't really do that. You can't really subsurface half of an object and expect not to have gaps. You really should sub patch a whole mesh or don't. Although I have seen people do it and get ok results, It is not generally a good idea. In your instance you may be able to get rid of the gaps using sub patch weights.

Turner
10-23-2004, 06:06 PM
Ok -

Any suggestions for alternatives?

My next stop is probably spline patches I guess.

Thanks,
Andrew


You can't really do that. You can't really subsurface half of an object and expect not to have gaps. You really should sub patch a whole mesh or don't. Although I have seen people do it and get ok results, It is not generally a good idea. In your instance you may be able to get rid of the gaps using sub patch weights.

ThriJ
10-23-2004, 07:13 PM
I on some occasions model temporary subpatch models connected to non-subpatch models.

Subdivide the connecting non-subpatch polygons and freeze the subpatch polygons. Then weld the two together.

Now if you don’t want the subpatch polygons frozen then you approach it differently.


Is that what your trying to accomplish?

Silkrooster
10-23-2004, 09:13 PM
One way around it maybe to just copy the selected poly and subdivide the copy. That way the original poly will fill in your gaps.
Silk

Turner
10-24-2004, 06:18 AM
Hi ThrilJ-

I tried that but it doesn't seem to get me where I'm going - after subpatching part of the model, I seem to have no reliable way to weld the subpatched polys to the non-subpatched ones...

Plus, I need to start with a "whole" model rather than parts in this case.

Thanks,
Andrew


I on some occasions model temporary subpatch models connected to non-subpatch models.

Subdivide the connecting non-subpatch polygons and freeze the subpatch polygons. Then weld the two together.

Now if you donít want the subpatch polygons frozen then you approach it differently.


Is that what your trying to accomplish?

Turner
10-24-2004, 06:32 AM
Hi Silk -

Tried this too, but because the subpatched polys "pull away" from the original surface without leaving their respective planes, the original polys simply obscure the duplicated subpatched polys.

Andrew


One way around it maybe to just copy the selected poly and subdivide the copy. That way the original poly will fill in your gaps.
Silk

Exception
10-24-2004, 07:25 AM
There is a good alternative, especially designed for this problem: spline modeling.
Using the Auto patcher and Patcher MK and read up on how to model using splines instead of metanurbs in the manual. This will solve your problem.

Skritter
10-24-2004, 08:53 AM
There is a way to have subpacthes join non subpatches

Use the "Subpatch Weights" Option to weight the affected points thus taking the subpatch effect off the joining areas and molding back into the non subpatched pollys

JulianW
10-24-2004, 09:21 AM
Hi,

yup you can do it, in just the way skritter said. You can blend subpatch sections with poly sections by careful use of the "SubPatch Weight" weight map. This example object is made from a sub patch bit and a box which is polygons:

The key is to make sure that the normals of the poly and sub patch meshes are as well aligned as possible, and set the "SubPatch Weight" is set to 100% for the shared points.

I've attached the object, all the best,


JW.

ThriJ
10-24-2004, 08:39 PM
Turner, after you Subdivide the connecting non-subpatch polygons and freeze the subpatch polygons you select a point from the frozen polys and a point from the non-frozen polys and then click the weld tool. There are about two or three ways of doing this. I'll post some examples when I can.

But before doing any of that, I think selecting the gap points and then going to Maps/ Set Map Value/ and setting the value to 100% may be the best option for what you are trying to do.

I don’t have LightWave on this computer. Therefore, I am telling you this from memory, so the names may be a little different.

Turner
10-24-2004, 08:50 PM
Thanks all...

Just wanted to let you know I checked in and read your posts and will work through these suggestions tomorrow -

Cheers
Andrew

ThriJ
10-25-2004, 01:44 PM
Turner, there are three basic ways to connect subpatch polygons to normal polygons.


1. Freeze the subpatch polys then subdivide the non-subpatch polys till it has the same amount of connecting points as the frozen subpatch polys then use the ( Weld ) tool to weld each frozen subpatch poly to each non-subpatch poly. Then cut and past the frozen polys.

2. Copy and past the subpatch mesh into another layer then freeze the subpatch in the first layer. Then select in order all the points on the right side of the frozen subpatch polys and the non-subpatch polys then hit the ( p ) key to make a connecting polygon then do the same thing on the left side. Now you delete the frozen subpatch polys and past the unfrozen subpatch polys back into the first layer.


3. Select the points connecting the subpatch to the non-subpatch polys and go to Map/General/Set Map Value and select [ base SubPatch Weight ] under the Vertex Map drop down window. Then set Value 1 to 100.0%.

well I got to get going so Good Luck Turner