View Full Version : Weight maps not compatible with Catmull-Clark subs ?

04-06-2011, 04:40 PM

im finding myself wondering if I have overlooked something too obvious but never learned.

I am used to using quads for all my sub patch modelling but have tried using the Catmull-Clark algorithm lately.

However as you can see in this image my weight maps have no transistion at all between polygons, is this something I can correct ?

Thanks to anyone who can help :)

04-06-2011, 05:21 PM
While I have a post about weight maps up, is there a way to select polygons within a specific threshold of weight value when I have the weight map selected ?

04-06-2011, 06:13 PM
This is just the opengl preview. And the CC-SubD weight preview is actually more correct. But neither show exactly what you get when you do a proper render.

You get "no transition" when the surrounding points have no weight value assigned. You can't interpolate between n% and a null value. n being any number and null meaning you haven't assigned any value. You get a smooth transition if you set the surrounding points to 0% (or any other value) because that allows interpolated values to be calculated.

Unfortunately, when you render a "no transition" you'll notice LW will still do some interpolation inbetween the subpolygons closest to the edge, on both subpatches and cc subds. As such position and the width of the transition will vary based on subd level. So you really should always surround a weighted area with 0% assignments to get a consistant and predictable result.

There are atleast two functions that can select vertices based on vmap values. "Select By VMap Influence" and "Cull Map". You can later convert that to polygons selection.

04-06-2011, 07:34 PM
Thank you for the thorough feedback evenflcw :)

Guess I should have hopped into Layout before judging the CC, just havent used much of it yet.

Also, great to know I can select my polys with an x amount of weight applied to them. Thanks again!