aalib

AA-lib is a low-level graphics library similar to many other libraries
except for the fact that AA-lib does not require a graphics device! In
fact, no "graphical" output is possible. AA-lib uses a modern, high-tech
ascii-art renderer in place of outmoded and cumbersome graphical output.

The AA-lib API is designed to be similar to that of other graphics
libraries so learning its API should be simple.