polygon_grid


polygon_grid, a Python code which generates a grid of points over the interior of a polygon in 2D.

The program relies on a simple idea in which the "vertex centroid" (average of the vertices) is computed, allowing the polygon to be triangulated. Each triangle can then easily be gridded. The collection of triangular grids joins up to form a grid over the polygon, although the spacing of the the grid points will vary from triangle to triangle.

The program really only works properly for convex polygons. If the polygon is not convex, then the vertex centroid need not lie inside the polygon, consequently the grid points may also seem misaligned.

Licensing:

The computer code and data files described and made available on this web page are distributed under the MIT license

Languages:

polygon_grid is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Data and Programs:

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square_grid, a python code which computes a grid of points over the interior of a square in 2d.

tetrahedron_grid, a python code which computes a grid of points over the interior of a tetrahedron in 3d.

triangle_grid, a python code which computes a grid of points over the interior of a triangle in 2d.

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Source Code:

ELL is an L-shaped (non-convex!) polygon for which the program output doesn't look too bad, although the grid is degenerate.

QUAD is a quadrilateral polygon.

TRIANGLE is a triangular polygon.


Last revised on 29 January 2020.