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dman99

01-22-2003, 04:22 PM

I am having trouble getting a perfectly smooth transition from one surface to another. I have too surfaces and whether I do a loft or free form fillet between isoparms I can still see small sections where the seem appears to be coming apart both in the workspace and in the final render. How do I get it perfectly seamless. Thanks for any help.

Flo

01-22-2003, 04:48 PM

hmmm ...there could be a couple of reasons for your probelm.

maybe your tesellation is too low (might be the case with the fillet) or, if its a patch model it might be a tangency probelm.
if so, you should have the same number of spans on each surface. then you can eg. blend attach or aling them to create a tangencial transition ..... whcih will render like there is no seam (like its 1 surface).

hope this helps,
Flo

dman99

01-22-2003, 04:58 PM

this is what I'm talking about..if I can get this picture link to work

Flo

01-22-2003, 05:00 PM

yep, looks like the tesselation is set too low .... switch to explicit (advanced) teselation and crank it up .

Flo

Flo

01-22-2003, 05:02 PM

...supposing that the transition is a tangent one , of course ...

F

dman99

01-22-2003, 05:03 PM

heres a shot of the render tesselation

dman99

01-22-2003, 05:10 PM

I went into advanced tesselation for each surface and enabled advanced tesselation, then under primary cranked up the number of U and V isoparms. Is that what you are talking about?...cause this still desn't fix it for some reason. By the way..thanks for the quick replies

Flo

01-22-2003, 05:10 PM

hmm ...looks quite strange , like the render output .... are you sure , both of these surfaces have the same number of spans etc ?

Flo

01-22-2003, 05:12 PM

hey .... maybe you want to send me those 2 surfaces , so i can have a look on them ....

this will fix the problem much faster

dman99

01-22-2003, 05:19 PM

Ok..here how I made this surface. I made a birail surface..mirrored it and then free form filleted the top two isoparms. where the free form fillet connects to the original surface is where the problem is. The both have the same number of spans. I am thinking it is some setting in the rendering, but I'm not sur what. Here is another pic showing the spans.

dman99

01-22-2003, 05:26 PM

check your email (flow@flow3d.com). Thanks again for the help

plotz

01-22-2003, 07:11 PM

In the tesselation attributes for your surfaces try turning on "smooth edges". This will add triangles at the edges of the surfaces and make the render blend a little better.

It's also a good idea to rebuild both surfaces to the same NURBS detail level (same number of divisions per surface in u and v.)

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