The Guile Picture Language provides a Guile library containing simple procedures to generate primitive shapes, to manipulate them, and to compose them to build complex pictures. While this library could be used to procedurally generate images, it is really meant to be used interactively.
Pictures in this language are first class values like numbers or strings, so they are displayed as actual pictures, not as text. We suggest using Guile Studio to play with the picture language, as it comes with everything you need to play with the picture language interactively.
Sound interesting? Take a look at the illustrated manual for many examples.