How do I maximize the window to multiple monitors in awesome wm?

Question

I have three monitors in a horizontal line. Sometimes i want to maximize a window to three monitors at once, by pressing a combination of keys (and then returning it all back if necessary). How can I do that?

Answer 1

Untested, but the basic idea is to make the window floating and resize it to cover everything:

function(c)
    c.floating = true
    local geo = screen[1].geometry
    geo.x2 = geo.x + geo.width
    geo.y2 = geo.y + geo.height
    for s in screen do
        local geo2 = s.geometry
        geo.x = math.min(geo.x, geo2.x)
        geo.y = math.min(geo.y, geo2.y)
        geo.x2 = math.max(geo.x2, geo2.x + geo2.width)
        geo.y2 = math.max(geo.y2, geo2.y + geo2.height)
    end
    c:geometry{
        x = geo.x,
        y = geo.y,
        width = geo.x2 - geo.x,
        height = geo.y2 - geo.y
    }
end

To undo the above, make the client no longer floating, i.e. c.floating = false.

Wiring the above to a keybinding is left as an exercise for the reader.