Split Tree output question

Grasshopper
1

Split tree had an option that if we connect 2 Masks , the Positive output would be the first mask and Negative output would be the second mask ,
As you can see here I showed how it should work :

image
image1579×650 115 KB

And how it is working now :
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image1429×730 116 KB

this is only the Positive output list in second image .
I don’t know why suddenly this option has changed …

Rhino : Version 8 SR24
(8.24.25251.22001, 2025-09-08)

2

I think the picture in your screenshots would produce a different grid, and that doesn’t really help me understanding the issue :slight_smile:

this is the grid I get with your screenshot components:

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image1443×610 48 KB

would you mind uploading your gh file?

3

split tree bug.gh (8.0 KB)
That’s because I used Dot Display to put it on forum and turned off unnecessary previews .
You should just see the positive and negative outputs separately
(as I said , the first picture is what we are expecting to see )

4

I was trying to understand the problem as well. I am not at Inno’s level of tree management, so apologies in advance if I get corrected following this comment.

However, based on my understanding:

P outputs positive side of the split*

*That is, whatever mask(s) you’re using, they precisely determine this ‘P’, while ‘N’ would be the other side of the split, correct? My take is you already know that.

So, when I see this:

image
image553×262 4.46 KB

My first thought is:
“the two masks are alternating which set of indices get picked depending on the branch…OR: for even branches, give me every other point starting at 1…for odd branches, also give me every other point BUT start at 0…”

Right? Sorry, exhausting, I know.

That IS what SplitTree is outputting as the {P} positive set.

5

Thank you for your comment , as long as I remember , if we used two masks , we would get both masks in order P and N outputs . Maybe I just mixed it up with another component or function …

6

??

Who knows! Not necessarily - maybe you had to dispatch the original grid first, plus entwine the dispatched elements, but that sounds like a slightly different question (vs split tree working oddly). The real/new question is why did you give yourself the solution? :rofl:

7

split tree 1.gh (11.3 KB)

‘P’ and ‘N’ outputting more or less like what you want?

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image1748×618 112 KB

split tree 2.gh (15.1 KB)

redundant:

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image1295×544 83.9 KB

*edit: I do acknowledge your question relates more to the use of the multiple masks, sorry - definitely don’t know :laughing:
cheers!

8

if more then one mask is supplied, they are sort of combined together with an OR logic behavior

so P (Positive) output will return data that matches at least one of the masks
while N (Negative) output will return data that did not match any of the masks

stupid example:

image
image1623×682 85.5 KB

9

Thanks, Actually because I realized that I mixed that with something else (as long as I even tried that in rhino 7 last night and it was the same ) I wanted to somehow show that It was my confusion so I decided to mark my post as solution :rofl::rofl:
But anyway thank you guys for continuing this topic so we can learn more from you

10

Hi René , now that I looked up your script , this is exactly what I was looking for . I really enjoyed your logic , Thanks (I will give you the solution :wink:)

11

IMG_6668

Haha all good - jokes aside though, honestly I asked yesterday because I was curious to learn myself what you had found out as solution and didn’t tell us :slight_smile:

Best!
RC