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I'm currently writing an algorithm that iterates along the boundary of different polygons and linestrings made with shapely. This works fine when I use circular shapes made using buffer, but when I make square shapes I get too few points to work with.

This picture shows basically what I have and what I want:

Example

I think I have seen something like this here before, but I have not been able to find it again.

from shapely.geometry import Point, LineString, Polygon
from shapely import affinity


def my_shape(position, scale):
    x, y = position[0], position[1]
    angle = - position[2]
    width = 30 * scale
    length = 50 * scale
    x_min, x_max = x - width / 2, x + width / 2
    y_min, y_max = y - length / 2, y + length / 2
    left_behind, right_behind = (x_min, y_min), (x_max, y_min)
    left_front, right_front = (x_min, y_max), (x_max, y_max)
    coordinates = [right_front, right_behind, left_behind, left_front]
    my_polygon = Polygon(coordinates)
    my_polygon_rot = affinity.rotate(my_polygon, angle, 'center')
    return my_polygon_rot
Etesravan
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  • Can you post your code of what you have done so far? Thanks – Costa Jul 16 '21 at 11:51
  • @Costa Cannot post whole code because of NDA, but I added the code which constructs the rectangle polygon made up of 4 points. What I wish to do is add more points along the boundary of this polygon without changing the code I posted. – Etesravan Jul 16 '21 at 12:25
  • This can be helpful: [How to get equally spaced points on a line in Shapely](https://stackoverflow.com/q/62990029/7851470). Also, I used these two functions in one of my projects: https://gist.github.com/LostFan123/9ff430e99cf558269ae23131ca005908 Maybe they can be of any help. – Georgy Jul 18 '21 at 17:35

0 Answers0