new wibox.layout.mirror

this allows to mirror a widget vertical and/or horizontal.

Signed-off-by: Uli Schlachter <psychon@znc.in>

lib/wibox/layout/init.lua.in

@@ -10,6 +10,7 @@ require("wibox.layout.align")
 require("wibox.layout.flex")
 require("wibox.layout.rotate")
 require("wibox.layout.margin")
+require("wibox.layout.mirror")
 
 module("wibox.layout")
 

lib/wibox/layout/mirror.lua.in

@@ -0,0 +1,124 @@
+---------------------------------------------------------------------------
+-- @author dodo
+-- @copyright 2012 dodo
+-- @release @AWESOME_VERSION@
+---------------------------------------------------------------------------
+
+local type = type
+local error = error
+local pairs = pairs
+local ipairs = ipairs
+local setmetatable = setmetatable
+local base = require("wibox.layout.base")
+local widget_base = require("wibox.widget.base")
+
+module("wibox.layout.mirror")
+
+--- Draw this layout
+function draw(layout, wibox, cr, width, height)
+    if not layout.widget then return { width = 0, height = 0 } end
+    if not layout.horizontal and not layout.vertical then
+        layout.widget:draw(wibox, cr, width, height)
+        return -- nothing changed
+    end
+
+    cr:save()
+
+    local t = { x = 0, y = 0 } -- translation
+    local s = { x = 1, y = 1 } -- scale
+    if layout.horizontal then
+        t.y = height
+        s.y = -1
+    end
+    if layout.vertical then
+        t.x = width
+        s.x = -1
+    end
+    cr:translate(t.x, t.y)
+    cr:scale(s.x, s.y)
+
+    layout.widget:draw(wibox, cr, width, height)
+
+    -- Undo the scale and translation from above.
+    cr:restore()
+end
+
+--- Fit this layout into the given area
+function fit(layout, ...)
+    if not layout.widget then
+        return 0, 0
+    end
+    return layout.widget:fit(...)
+end
+
+--- Set the widget that this layout mirrors.
+-- @param layout The layout
+-- @param widget The widget to mirror
+function set_widget(layout, widget)
+    if layout.widget then
+        layout.widget:disconnect_signal("widget::updated", layout._emit_updated)
+    end
+    if widget then
+        widget_base.check_widget(widget)
+        widget:connect_signal("widget::updated", layout._emit_updated)
+    end
+    layout.widget = widget
+    layout._emit_updated()
+end
+
+--- Reset this layout. The widget will be removed and the axes reset.
+-- @param layout The layout
+function reset(layout)
+    layout.horizontal = false
+    layout.vertical = false
+    layout:set_widget(nil)
+end
+
+--- Set the reflection of this mirror layout.
+-- @param layout The layout
+-- @param reflection a table which contains new values for horizontal and/or vertical (booleans)
+function set_reflection(layout, reflection)
+    if type(reflection) ~= 'table' then
+        error("Invalid type of reflection for mirror layout: " ..
+              type(reflection) .. " (should be a table)")
+    end
+    for _, ref in ipairs({"horizontal", "vertical"}) do
+        if reflection[ref] ~= nil then
+            layout[ref] = reflection[ref]
+        end
+    end
+    layout._emit_updated()
+end
+
+--- Get the reflection of this mirror layout.
+--  @param layout The layout
+--  @return a table of booleans with the keys "horizontal", "vertical".
+function get_reflection(layout)
+    return { horizontal = layout.horizontal, vertical = layout.vertical }
+end
+
+--- Returns a new mirror layout. A mirror layout mirrors a given widget. Use
+-- :set_widget() to set the widget and
+-- :set_horizontal() and :set_vertical() for the direction.
+-- horizontal and vertical are by default false which doesn't change anything.
+local function new()
+    local ret = widget_base.make_widget()
+    ret.horizontal = false
+    ret.vertical = false
+
+    for k, v in pairs(_M) do
+        if type(v) == "function" then
+            ret[k] = v
+        end
+    end
+
+    ret._emit_updated = function()
+        ret:emit_signal("widget::updated")
+    end
+
+    return ret
+end
+
+setmetatable(_M, { __call = function(_, ...) return new(...) end })
+
+-- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80