This command (without any arguments) reloads the game shaders. You can optionally specify either a mapname, postfx or filename (ending in .fx).
reloadfx [map / .fx file]
| Map / .fx File | Optional. You can optionally specify a map name, postfx or specific file name to reload (shader files end in .fx). |
reloadfx map
The above command would reload the map shaders.