Hello,

my challenge may have already been solved, or it may be difficult for me. Maybe I'm just missing something:

i have a line dataset and a point dataset. the points are measurement points of the lines. in our convention, a line has 2 measurement points, an arc has three measurement points and splines have at least 4. there is no attributive connection between the two datasets. the measurement points are identical to the corresponding veritces of the lines 3D.

the line represents the upper edge of the sidewalk and i derive the lower edge of the sidewalk (street level) from a point cloud. due to the point cloud, the lines jump at the vertices in height along the line. i want to interpolate the line and have so far fed the 3D interpolator with the start and end point of the line and let it interpolate the line. so far so good.

but now i want the lines to be interpolated not only at the start and end points, but always exactly at the vertices at which a measuring point from the point data set exists. an example would be a circular arc: if i split the line with the chopper, the line has e.g. 50 vertices. I would now like to select only the three measurement points of the arc (start-, middle- and endvertex) and interpolate the arc using these three measurement points. 

How can I do this? Do you have any ideas?

Thanks for your help
René

Line support point

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