**triangle_grid**,
a C++ code which
generates a grid of points
over the interior of a triangle in 2D.

Starting with any 3 points A, B, and C that define a triangle, we can divide each side of the triangle into N subintervals, and create a triangular grid. This defines ((N+1)*(N+2))/2 points that lie on the intersections of grid lines. The arrangement is suggested by this diagram:

X 9 X 8 9 X 7 8 9 X 6 7 8 9 X 5 6 7 8 9 X 4 5 6 7 8 9 X 3 4 5 6 7 8 9 X 2 3 4 5 6 7 8 9 X 1 2 3 4 5 6 7 8 9 X 0 1 2 3 4 5 6 7 8 9 X

The library includes a routine which allows the user to pick an arbitrary triangle and an arbitrary number of subdivisions. It then returns the triangular gridpoints defined by that choice.

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

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

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

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

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

TRIANGLE_INTERPOLATE, a C++ code which shows how vertex data can be interpolated at any point in the interior of a triangle.

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

- triangle_grid.cpp, the source code.
- triangle_grid.sh, compiles the source code.
- triangle_grid.hpp, the include file.