how to select edge procedurally

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is there a way to select an edge procedurally?
or convert from a primitive to edges or point to edges procedurally ?

coz i cant find it in the help file

btw when is the documentation will be complete?any dates?
coz theres lot of TBD in there.. hard to learn stuffs if the help isnt complete

thx patar
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Use Edit sops.
But really, as you determine your selection with the Selection masks at Sop level, most sops remember the type of selection.
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patar
is there a way to select an edge procedurally?
or convert from a primitive to edges or point to edges procedurally ?

I've had some success using Simon's GroupEdges SOP available from here:
http://www.fourthwall.ndo.co.uk/HT_HDK_GroupEdges.html [fourthwall.ndo.co.uk]
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I am trying to do the same as described in this topic.

However the tool supplied doesn't work with Houdini 10…
Does anyone have a working solution in Houdini 10 or another custom tool?

The delete SOP doesn't delete lines but automaticly connects remaining points.


To clarify, this is the result I want to achieve.

Howver I did do this manually and I want this done procedurally.
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Schuey
To clarify, this is the result I want to achieve.
Howver I did do this manually and I want this done procedurally.

Use carveSOP, set first U to 0 ans second U to 1 and turn on Cut all internal U Breakpoints. Then use deleteSOP and delete unneded edges with your algoritm and fuse whats left.
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Schuey
To clarify, this is the result I want to achieve.
Howver I did do this manually and I want this done procedurally.

Use carveSOP, set first U to 0 ans second U to 1 and turn on Cut all internal U Breakpoints. Then use deleteSOP and delete unneded edges with your algoritm and fuse whats left.
Thanks, but that last bit is precisely what I'm not getting Houdini to do in a procedural fashion.

Right now in the dissolve node it says “p2-3 p6-7” in the group input. I want to be able to use an expression t control which edge is deleted, so I can end up with multiple primitives in 1 node. I'm going to sweep some objects over those points later on, and I want those objects to be also 3 seperate primitives.
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Right now in the dissolve node it says “p2-3 p6-7” in the group input. I want to be able to use an expression t control which edge is deleted, so I can end up with multiple primitives in 1 node.

With my technique you can use primitive numbers instead of point numbers to delete which edge is deleted. Than you can sort them like you want and delete them more easilly then by specifing points.




Or maybe I'm not geting what you want to do.
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Ah I see, that is interesting.
Only thing is that I don't quite know how to use my point selections to select the proper primitives. Can this be converted somehow? That would be great and probably solve my issue!

Btw, did you knew about this solution before or did you figure it out on the fly?
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I used it before in one of my tools. I supose it was Bridge Polygon tool.

If you are interested, check this thread http://forums.odforce.net/index.php?/topic/9707-my-tools/ [forums.odforce.net]
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If you apply this metod to picture below primitive 0 will be where point zero starts, prim 4 where point 4 starts and so on. There will be no prim 8 because it has beginning but no end so it doesn't exist. Worse if you dont have points sorted nicely like here.

Schuey

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Dude, thanks!
I just figured out an easy way to select and delete those primitives

What I can do is measure every primitive, and select and delete every primitive which is longer than the distance between points on my base curve. Trying that out next thing in the morning, hope this works!

(have been stuck on this for about a week now :x )
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Thanks man my problem is solved
After the fuse node, I used a join node to join the primitives together

Then I created the expression which calculates the length of seperate segments. Though I had a small problem where I was trying to divide a float value by an integer value, I fixed that as well. (by creating an attribute with float values)
prim(“../measure2”,“$PR”,“perimeter”,0) > (prim(“../measure1”,“$PR”,“perimeter”,0)/$SEGMENTS)

Houdini can be so frustrating if you don't know what to look for sometimes Love/Hate relationship thing, most of the time hate wins

Btw, I talked to the creator of that Edgegroup tool, and maybe he is going to recompile a version for Houdini 10
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