negow 0 Posted November 5, 2009 Seems easy enough, remove each and every edgeloop so to de-subdivide a mesh. Zbrush has a way, but having it as a node would make my life a bit easier. The subdivision is Catmull-clark based, so the must be some logic behind vertexorder and such. At least I think so. Example. A box (8 points) -> Subdivide (26 points) -> Edit some of the verticies, sure -> De-Subdivide (8 points) Is there a nice way of accomplishing this? Share this post Link to post Share on other sites
daniel.phillis 1 Posted July 11, 2010 (edited) bit of a late post, but Rob Kelly nutted this out for me. unsubdivided_example.hipnc Edited July 11, 2010 by daniel.phillis 1 Share this post Link to post Share on other sites
Fabiano Berlim 13 Posted July 11, 2010 bit of a late post, but Rob Kelly nutted this out for me. Very smart solution! Thanks for sharing! Share this post Link to post Share on other sites
bunker 287 Posted July 12, 2010 Very cool technique indeed bit of a late post, but Rob Kelly nutted this out for me. Share this post Link to post Share on other sites
sparkChan 1 Posted October 10, 2010 bit of a late post, but Rob Kelly nutted this out for me. thanks for your post, it is useful for me. Share this post Link to post Share on other sites
fxrod 25 Posted October 10, 2010 This is so much nicer than polyreduce! I have a question, though. The delete SOP is reducing every 1 out of 2 prims. Obviously, this requires a certain ordering of the polygons. I'm wondering what the sort order is on the original piece of geometry. Is it a standard modeling procedure? 1 Share this post Link to post Share on other sites
kgoossens 83 Posted September 16, 2012 bit of a late post, but Rob Kelly nutted this out for me. It would be good to post this on Orbolt. Share this post Link to post Share on other sites
A. Morales 6 Posted April 25, 2016 On 10/10/2010 at 2:49 PM, fxrod said: This is so much nicer than polyreduce! I have a question, though. The delete SOP is reducing every 1 out of 2 prims. Obviously, this requires a certain ordering of the polygons. I'm wondering what the sort order is on the original piece of geometry. Is it a standard modeling procedure? fxrod did you ever manage to figure this out? Share this post Link to post Share on other sites
3dome 132 Posted June 8, 2016 (edited) On 4/25/2016 at 6:01 PM, A. Morales said: fxrod did you ever manage to figure this out? It appears to only work with the way Maya is ordering the polys. -> works with geo coming from maya To see the difference: Export a .obj cube from maya and compare point numbers/prim numbers in Houdini to a houdini box object. Also in maya hit "3" and convert that preview to polygons. expor that too. In Houdini take a box, subdivide (catmull-clark, depth = 2) and the append delete sop with "range [1 of 2]". Same delete sop applied to smoothed maya cube will give you the result you want while on houdini subd box it fails. I yet have to find a way to reorder any geo in houdini to work with that method or change the method to work with houdini's way of ordering polys. Edited June 8, 2016 by 3dome hit enter on accident before finshing the post Share this post Link to post Share on other sites
animatrix 210 Posted June 8, 2016 You can implement this paper which wouldn't care about point/primitive numbers. http://wscg.zcu.cz/wscg2006/Papers_2006/Full/B89-full.pdf Share this post Link to post Share on other sites
3dome 132 Posted June 14, 2016 yea. will do when i find time. or you switch to zbrush for that task, they have this implemented. but be sure to have a geometry as input that got its shape by subd. if you subd and then just delete a single face, the algorithm wont work Share this post Link to post Share on other sites