How to extrapolate a point from Brep with specific distance

Hallo dear rhino community,

Maybe is a dumb question, but as beginner I don´t find a fast solution.

I need to extrapolate from one/multiple surfaces (like windows), always a reference point on the central axis, wich is distant X cm (per Example 0.30cm), from the bottom line of the surface.

Is there a way to automatically create this point, insert only the surfaces as input?

Thanks in advance

John R.

this might work for planar surfaces


john window BVR (7.4 KB)


Ciao @inno,

thanks for your time and solution,

but I have a error with the constructPoint component.

I insert your expression but don´t Work!!! (Expression did not return a valid value)
Can you please share me the GH file?


Surface Example
john window BVR re (9.3 KB)

Thanks @ajarindia,

this is a very good solution, I just have to be careful that the surfaces are all built in the same way, otherwise it does not match the side of the surface from which to extrapolate the point.

John R.

here it is (7.1 KB)

in the expression editor, just " x/2 " is needed

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