For copying information see COPYING. After that, perhaps look at the ChangeLog.

Commandline parameters:
=======================

The first argument (which is optional) is the tile path, if a tilepath
is specified horizon runs in windowed mode.

Keybindings:
============

Cursors keys: pan 1/3 of the canvas in a direction
F7,F8       : zoom in/out
return      : toggle to paint (or pick if already using paint)
Escape      : undo