Split polygon by regard of distance to other shapefile

Question

Is there some function that use distance to point/polyline layer to split a polygon layer

In Sweden the law says that undivided water belongs to the nearest property so sometimes I need to calculate what parts of a lake that belong to which real estate. Now I have to do it in several steps but I wonder if there are any function that I can use. I divide the beach-line into separate polylines (per real estate) but can I split the lake-polygon I separate polygons in regard of nearest polyline.

I have the same problem sometimes when calculate in forest when I have to divide the forestland in regard of gathering point for the logging but then I use a point layer to divide the polygon calculate where

Now I use multiple buffer zones then manually split the polygon "along the fold" of the buffers

Edit: Added two pictures so you maybe understand better

Exempel, red lines are divided water and I added green on undivided water

I used point grid and connected to nearest polyline-feature then I have to manually split along the color

Answer 1

You can :

1. create centroids of your buldings
2. use Voronoi Polygons with those centroids
3. clipped the polygons with the water surface

If you also need the beach line, you can create the boundary of your water surfaces and clip it with the Voronoi Polygon aswell.

You can also create centroids for line features.

Example:

Buildings are in purple, red and dark blue. Water surfaces are represented in light blue.

Centroid creation:

Voronoi Polygon creation:

Voronoi Polygon clipped by water surface (Water surfaces are divided depending on the closest building):