# polygon_grid

polygon_grid, a C++ 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.

### 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:

BALL_GRID, a C++ code which computes a grid of points over the interior of a ball in 3D.

CIRCLE_ARC_GRID, a C++ code which computes points equally spaced along a circular arc;

CUBE_GRID, a C++ code which computes a grid of points over the interior of a cube in 3D.

DISK_GRID, a C++ code which computes a grid of points over the interior of a disk in 2D.

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LINE_GRID, a C++ code which computes a grid of points over the interior of a line segment in 1D.

PYRAMID_GRID, a C++ code which computes a grid of points over the interior of the unit pyramid in 3D;

SIMPLEX_GRID, a C++ code which generates a grid of points over the interior of a simplex in M dimensions.

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SPHERE_LLT_GRID, a C++ code which uses longitudes and latitudes to create grids of points, lines, and triangles on the surface of the unit sphere in 3D.

SQUARE_GRID, a C++ code which computes a grid of points over the interior of a square in 2D.

TETRAHEDRON_GRID, a C++ code which computes a grid of points over the interior of a tetrahedron in 3D.

TRIANGLE_GRID, a C++ code which computes a grid of points over the interior of a triangle in 2D.

WEDGE_GRID, a C++ code which computes a grid of points over the interior of the unit wedge in 3D.

### Source Code:

Last revised on 31 March 2020.