Shoebot is described as 'pure Python graphics robot: It takes a Python script as input, which describes a drawing process, and outputs a graphic in a common open standard format (SVG, PDF, PostScript, or PNG)' and is an app in the Development category. There are more than 10 alternatives to Shoebot for Windows, Mac, Linux and Online / Web-based. The best alternative is Processing, which is both free and Open Source. Other great apps like Shoebot are Pure Data (Free, Open Source), Cinder (Free, Open Source), Vvvv (Free) and Nodebox (Free, Open Source).
Processing is an open source programming environment and library built to handle images, animation, and interactivity. It is used by students, artists, designers, researchers, and hobbyists for learning to code, prototyping, and producing full applications.
Pd (aka Pure Data) is a real-time graphical programming environment for audio, video, and graphical processing. It is the third major branch of the family of patcher programming languages known as Max (Max/FTS, ISPW Max, Max/MSP, jMax, etc.
vvvv is a graphical programming environment for easy prototyping and development. It is designed to facilitate the handling of large media environments with physical interfaces, real-time motion graphics, audio and video that can interact with many users simultaneously.
Orca is an Esoteric Programming Language and live-coding environment for musical experimentation. In Orca, each letter of the alphabet is an operation, lowercase letters operate on bang, uppercase letters operate each frame.