Over the last two years, I have been developing for my work a modular video-mapping software, primarily used for fulldome projections but which really can be used for anything. Named Splash, this open-source software has the ability to output to any number of projectors (even through dual and triple heads), from live inputs or video files.
As of yet it has mainly been used internally, so the user interface is a bit rough. We use it to map our 20m dome with 8 projectors, and it has already been used with smaller domes (a 16m inflatable one with 5 projectors, and a small 3m with 4 projectors). For testing purposes I used it with a single pico-projector, so this should give you the idea of the kind of configuration Splash handle.
Now for the link with Blender: I have been a Blender user for a couple decades, and so I chose Blender as the software of choice to create the 3D models to feed to Splash. I create an addon which allows for configuring Splash from the node editor. Also, with a bit of work, it is possible to feed Splash with a mesh modified in real-time inside Blender.
Splash currently runs on Linux (packaged for Ubuntu and siblings) and OSX, you can find the installation instructions in the wiki:
If you happen to use this software, I would be happy to answer any question and I’m open to suggestions to improve it.