FlowVitae
A very memory efficient and fast library for creation of (infinite) procedural and static grids.
This library has some Visualizer projects that serve as examples on how to integrate the library with some rendering engines such as SadConsole and MonoGame.
I use this library in pretty much all of my tile based games, it is therefore also updated frequently with bugfixes and new features.
It is available as an MIT licensed opensource library on Nuget and on GitHub.
Code 2D 
