Draw 2D geometry in MonoGame/XNA, including primitives such as lines and polygons.
These samples are included in the source.
An example of how to draw simple shapes in a grid. You can easily change the scale, grid type (triangle, square, hexagon) and color in the sample code.
An example of how to animate the shapes you draw.
- LibTessDotNet - Polygon tesselation (and triangulation).