Jump to content
Sign in to follow this  
probiner

Hard Edges

Recommended Posts

Hi
I was looking for a way to mark/group edges and make them hard in terms of smoothing and this is what I came up with:
6filOPN.png
 

I couldn't find a standard way to do this. Maybe an edge option in the Normal node would be cool.

Cheers

 

HardEdges.hipnc

Edited by probiner
  • Like 1

Share this post


Link to post
Share on other sites

here's mine...it maybe clunky..but it does use only whatever 'standard' nodes avail...

vu_HardEdges.hipnc

Actually, I just tried simply plugging in your scene to an edgecusp (skipping the subnet) and it works...am I missing something really obvious ?

OK, a bit clearer now...I'm selecting faces/prims while you're selecting edges...so you could be trying to 'crease' some single line rather than a closed loop from some faces....still, once you've got the lines I'm  puzzled why you don't just feed it straight into an edgecusp ?

Edited by Noobini

Share this post


Link to post
Share on other sites

Hi Noobini, because I want to persever the geometry. I just want to have Hard Edges based on marking and Edge Cusp opens the geometry, which you can see by simply plugging a Point Jitter with a small amount after it, the mesh opens, I want the same exact mesh but with hard edges.

Cheers

Share this post


Link to post
Share on other sites

no my question is why bother with the subnet ? after you've selected the edges...why not plug them straight into edgecusp ? why overcomplicate thing with the subnet ?

Edited by Noobini

Share this post


Link to post
Share on other sites

Edge Cusp opens the mesh. Now, the scene I've uploaded first did not have the subnet output the proper node (Attribute VOP) so the sense of it might have been lost. Sorry about that.
OP scene file fixed.

V9YrAdI.gif

Cheers

Edited by probiner
  • Like 1

Share this post


Link to post
Share on other sites

I just noticed though that while you can't set the normals on edges, you can use a group of edges... So there's that.... x)


Edge Group > Set on Vertices with 0 threshold!

Eh!

Share this post


Link to post
Share on other sites
On 22/07/2017 at 2:56 PM, probiner said:

Edge Cusp opens the mesh. Now, the scene I've uploaded first did not have the subnet output the proper node (Attribute VOP) so the sense of it might have been lost. Sorry about that.
OP scene file fixed.

V9YrAdI.gif

Cheers

ahhhh that's why I was puzzled....couldn't see the point when your sphere was still being split (with jitter)

yeah so now if I put display flag on the attribvop, your sphere doesn't get split anymore....thanks for pointing out.

And I noticed Facet opens up a mesh as well....hmm.....

Edited by Noobini

Share this post


Link to post
Share on other sites

You have principly two ways in houdini you can make hard edges. With manipulating normals of points or manipulating normals of vertices. Any way to make a hard edge when manipulating point normals works in such a way, that a point is "opened up" or made unique. Means from one point you will get more points which have a normal and therefore a hard edge if the normals are not identical.

The other way is to use vertices. There is a trick which enables you to circumvent the "opened up" mesh. The first step is to generate point normals (normal SOP, and select points in the options). Then you can edge cusp to get a hard edge (like in the method described above). But the hard edge generates unique points ("upened up" mesh). So to solve this issue you promote the point normals to the vertices with the Attribute Promote SOP and then you fuse the unique ("opened up") points. This way you will have your hard edges and the mesh will not be opened up. 

At the bottom there are some pics to depict this method.

normal.PNG

attpromoto.PNG

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×