Gaffer is an open source application framework designed specifically for creating tools for use in visual effects production. It builds on top of the Cortex libraries, adding a flexible node-based computation framework and a user interface framework for editing and viewing node graphs. Gaffer ships with a number of sample modules and applications, not least of which is a module for the on-demand generation of procedural scenes for rendering.

More information can be found on the project homepage: http://imageengine.github.io/gaffer

Developer notes are available on the project wiki.