CompuServe Thread

#Smoothing Question

10 messages in this thread
#146503From: Glenn ZimmermanJan 13, 1995 8:55 AM
I have a question. I built a logo in 3D, then used the MELT software to get it to collapse into a pool. No problem. However, in rendering I get occasional sharp triangles appearing on certain frames, like the smoothing is getting confused. I've tried re-smoothing each morph shape and I do have morph smoothing turned on. Is there any way to get rid of these sharp edges? thanks.
#146529From: Yost GroupJan 13, 1995 10:00 AM
The Melt routine needs quite a bit of faces for a smooth effect, and it sounds like your logo needs a little more complexity. Try using Create/Object/Tessellate before melting it. – G
#146531From: Glenn ZimmermanJan 13, 1995 10:06 AM
That's probably it. I'm getting the most rough edges on the front of the logo, which is flat. Thanks.
#147049From: Glenn ZimmermanJan 16, 1995 10:14 AM
Well, I tried tesselating the objects. The problem is, the object is broken up into trinagles in such a way that there are quite a few long, pointy faces. Tesselation only adds more of those faces. This is where I'm getting the "wrinkles* in my smooth surfaces. Is there a way to break up a surface with a grid (Wavefront does this with their tesselation command)? I've also tried adding more points to the original 2D shape to get it to break up differently, but that didn't seem to help (the main culprit here is the letter "R" with its 2 legs and a hole in the middle!).
#147199From: Yost GroupJan 16, 1995 9:37 PM
If you have Optimize.pxp, you can select specific regions for tessellating for more-local operations. Re gridding the surface… that's an excellent candidate for an IPAS routine! – G
#147290From: Glenn ZimmermanJan 17, 1995 8:10 AM
Oh yeah, and another thing. I tesselated the object, then melted it and got strange spiky points sticking out all over! Very weird! Apparently there's no one-step way to fix my problem. Sounds like I'll have to do a little manual "diddling". Normally the 3-D type looks fine. It's when I melt the darn thing that I run into problems.
#147217From: John K. JordanJan 16, 1995 10:46 PM
>>long, pointy faces… Hello Glenn. PMJI, but if adding a few extra vertices in the shaper doesn't create the desired mesh, you can usually break up the faces with a little manual application of Modify/Edge/Divide and Modify/Edge/Turn, perhaps followed by a little Modify/Vertex/Weld if necessary. (Hide all the faces behind first.) With these three commands you can massage the faces until they are exactly as you want them without changing the mesh surface shape. I have fixed a bunch of smoothing wrinkles like this. If you haven't used Edge/Turn much, just be careful to avoid making a face with zero area. For example, Turning the center (vertical) edge in the left diagram below will result in a bogus face squashed into the horizontal line in the diagram on the right: +—-+—-+ +—-+—-+ \ | / \ / \ | / \ / \ | / \ / \|/ \ / + + Another no-no is to Turn the edge between a pair of faces similar to those above but where the horizontal line forms a concavity. This will result in overlapping co-planar faces, but at least you can recover quickly by turning the edge again. As Edge/Divide will create a new vertex in the plane of the original face, you can even move the new vertex around to suit if you first align a User View to the face. Now what would REALLY be useful is a Modify/Edge/Refine command – that would save a lot of time in face editing. (Is Mr J-WishList-R listening?) JKJ
#147230From: MARTIN G FOSTERJan 16, 1995 11:43 PM
JKJ, >> Modify/Edge/Refine command << I've wanted that for ages – I'll second your wish.
#147291From: Glenn ZimmermanJan 17, 1995 8:12 AM
What? You mean release 4.0 doesn't have the "Fix Everything" button installed yet? Darn! I'll give your suggestions a try & see what happens. Thanks.
#147294From: Jonas Ruikis [ADESK]Jan 17, 1995 8:22 AM
<< Now what would REALLY be useful is a Modify/Edge/Refine command – that would save a lot of time in face editing. (Is Mr J-WishList-R listening?) >> got it.