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banacan
01-25-2008, 04:05 PM
Hi All,

I'm using LW 9.0 on the MAC and I'm having a bizarre problem. I'm including images so you can see what I'm talking about. I loaded a 3DS object from Autocad and I'm trying to merge polygons to create a smoother curve. When I do I get this strange shadow entity that is affecting my rendering. I don't know what this is but it only appears when I merge the poly's. In the second image you can see that it is now one poly but there is this "shadow" over the actual shape. Can anyone tell what is happening here?

Mr Rid
01-25-2008, 04:54 PM
This is a severely 'non-planar' polygon. Polygons need to be flat to render correctly. The merge is forcing a flat poly to conform to the curved shape of your side polys. If your intention is to flatten the top of the object then just delete those unuseful points left after the poly merge.

While in polygon mode, click W to bring up the polygon stats, and click 'non-planar' to locate problem polys.

meshpig
01-26-2008, 02:43 AM
... not a very clear picture, but that's normal when importing 3DS.

After you unify the polys, go to wireframe view and pick out all the isolated points or go to "w" stats/points and delete the 1/0 point polys.

3DS models aren't much use in LW, unless you are going to pick them apart and partially rebuild.

m

banacan
01-26-2008, 09:13 AM
Mr. Rid,

Aren't polys used in everything we construct, even those items that need to be curved? How does one make a continuous smooth curve from multiple polys without it being faceted? Obviously I can't use subpatching because I lose the sharp edges and it distorts the final shape. You can see what I need to construct, what would be a better way?

Meshpig,

Thanks for your reply. I guess I'm confused about how a poly is used. I didn't know that they are only to be planer. I guess the 3DS files are not useful I sure hope I don't need to re-create all of the hundreds of files that I need to render! What an undertaking that would be.

JeffrySG
01-26-2008, 09:59 AM
This is a severely 'non-planar' polygon. Polygons need to be flat to render correctly. The merge is forcing a flat poly to conform to the curved shape of your side polys. If your intention is to flatten the top of the object then just delete those unuseful points left after the poly merge.

While in polygon mode, click W to bring up the polygon stats, and click 'non-planar' to locate problem polys.
Totally agree....

Also, if you are trying to get a smoother curve, instead of merging those polys - why not just use rounder on some of the individual edges (the ones that go from left to right on the screen grab) that make up the curve to smooth it out a bit more? You could then smooth it out as much as you needed. Should not take that long to do.

banacan
01-28-2008, 12:31 PM
Thanks for all of the responses.

I'm embarrassed to say that the solution to my problem wasn't in the modeling at all; as usual I made it much more difficult than it needed to be. All I really needed to do was to adjust the Smoothing in the Surface Editor and I got exactly what I was looking for.

Sorry for the wild goose chase, but thanks for listening.