[QUESTION] Clamping parameter inside detail attribute?

[neblina]

Hello everyone, here's the issue I'm encountering:

From a set of points I'd like to delete all but one of them, and with a slider on the upper level be able to select which. I managed to to that, but if the slider has a value bigger than the total number of points I have a problem. So I thought about maybe clamping the slider value between 0 and the total number of points. I don't know if that is possible, but here's what I tried so far:

Attribute Create node (posAttr) with a detail attribute (posAttr) with the following value: clamp(ch("../posParm"), 0, $NPT)

After that a Delete node, Delete by Expression, Filter: $PT == detail("../posAttr", "posAttr", 0)

I expected this would evaluate the value coming from the ch in the upper level and always clamp it between 0 and the number of points, but instead it does nothing. If the value goes past the number of points it still 'crashes'. If this is a completely wrong approach, how else could I accomplish this? Thanks in advance!

[Parboil]

Hope this helps. I used a detail wrangle.

int pt = chi("center_pt");

int upper = clamp(pt + chi("upper"), 0, npoints(0));
int lower = clamp(pt - chi("lower") -1, 0, npoints(0));

for (int i = lower; i< upper; i++){
    removepoint(0, i);
}

 

[Noobini]

try this ?

clamp.hipnc

[neblina]

Yes, thank you. Somehow I figured this out yesterday, subtracting 1 from the $NPT does the trick.

clamp(ch("../posParm"), 0, $NPT - 1)

Just like your example, @Noobini.