# Trying to build a shutter with Geo nodes

I'm trying to build a shutter following the workflow depicted by the image.

The logic is to raise the lowest point till it meets the 2nd lowest point, and then they raise together till they meet the 3rd one and so forth. So far I managed to select incrementally the lowest point following a float value, but the main problem is: once the lowest point meet the 2nd lowest point, this last one compensates the distance by popping upwards, and, in the end of the operation, all points go up by the offset value input in the 'set position' node and they finish looking exactly like they started, only a bit higher. The solution would be to associate each point with a different moment of this offset, but I don't even know whether it's possible. Can somebody throw me an idea? Thx!

In case you want the points to stack on top of each other:

The maximum option in the Math node is useful in this case. It can be used to output the biggest value of it's inputs.

What needs to happen is that the point needs to go up only when the offset is greater than it's starting $$Z$$ position.

If we subtract the starting $$Z$$ from the offset and use the Maximum node with the resulting value and the other value as $$0$$, the point will only move up when the offset reaches the $$Z$$ position, and it will stay at the original position if the offset is lower than the starting position.

If what you want is that the instances stack on top of each other instead of intersecting, you will need to multiply the height of the instance by the point index, the result is then added to the value before clamping.

you can use this node setup to get what you want:

Set the offset of the meshline of x to 0 to get your effect. i just set it to 1 that you can see, that my node tree works.

result:

result with x offset 0: