This is fork is highly modified version of this project and used as in-house development tool. Use at your own risk.
This is a rudimentary emulator of the Novation Launchpad.
It uses the web MIDI API to communicate with other hardware and software devices. You will be prompted to approve access when first using the emulator.
It automatically connects itself to all available MIDI inputs and outputs on your system once MIDI access is approved. A menu for connecting / disconnecting devices is on the TODO list.
The code to draw the Launchpad on screen was inspired by Olivier Croisier's LP4J project. I wrote my own implementation to handle button values differently, but it's pretty clear I had LP4J code fresh on my mind when I wrote my function.