lib/revelation.lua.in

   1 ---------------------------------------------------------------------------
   2 -- @author Espen Wiborg &lt;espenhw@grumblesmurf.org&gt;
   3 -- @author Julien Danjou &lt;julien@danjou.info&gt;
   4 -- @copyright 2008 Espen Wiborg, Julien Danjou
   5 -- @release @AWESOME_VERSION@
   6 ---------------------------------------------------------------------------
   7
   8 local math = math
   9 local table = table
  10 local pairs = pairs
  11 local button = button
  12 local otable = otable
  13 local awful =
  14 {
  15     tag = require("awful.tag"),
  16     client = require("awful.client")
  17 }
  18 local capi =
  19 {
  20     tag = tag,
  21     client = client,
  22     keygrabber = keygrabber,
  23     mouse = mouse
  24 }
  25
  26 --- Exposé implementation
  27 module("revelation")
  28
  29 -- Layout functions
  30 layout = {}
  31
  32 --- The default layout function for revelation
  33 -- Tries to arrange clients in an approximated square grid, by
  34 -- calculating c = floor(sqrt(n)) and arranging for c columns in a
  35 -- tile layout.
  36 -- @param t The tag to do revelation on.
  37 -- @param n The number of clients to reveal.
  38 function layout.default (t, n)
  39     t.layout = "tile"
  40     local columns = math.floor(math.sqrt(n))
  41
  42     if columns > 1 then
  43         t.mwfact = 1 / columns
  44         t.ncol = columns - 1
  45     end
  46     t.nmaster = n / columns
  47 end
  48
  49 function clients(class, s)
  50     local clients
  51     if class then
  52         clients = {}
  53         for k, c in pairs(capi.client.get(s)) do
  54             if c.class == class then
  55                 table.insert(clients, c)
  56             end
  57         end
  58    else
  59         clients = capi.client.get(s)
  60    end
  61    return clients
  62 end
  63
  64 function selectfn(restore)
  65     return function(c)
  66                restore()
  67                -- Pop to client tag
  68                awful.tag.viewonly(c:tags()[1])
  69                -- Focus and raise
  70                capi.client.focus = c
  71                c:raise()
  72            end
  73 end
  74
  75 --- Returns keyboardhandler.
  76 -- Arrow keys move focus, Return selects, Escape cancels.
  77 -- Ignores modifiers.
  78 function keyboardhandler (restore)
  79     return function (mod, key)
  80                 if key == "Escape" then
  81                     restore()
  82                     awful.tag.history.restore()
  83                     return false
  84                 elseif key == "Return" then
  85                     selectfn(restore)(capi.client.focus)
  86                     return false
  87                 end
  88                 return true
  89            end
  90 end
  91
  92 --- Implement Exposé (from Mac OS X).
  93 -- @param class The class of clients to expose, or nil for all clients.
  94 -- @param fn A binary function f(t, n) to set the layout for tag t for n clients, or nil for the default layout.
  95 -- @param s The screen to consider clients of, or nil for "current screen".
  96 function revelation(class, fn, s)
  97     local screen = s or capi.mouse.screen
  98     local layout_fn = fn or layout.default
  99     local data = otable()
 100
 101     local clients = clients(class, screen)
 102     if #clients == 0 then
 103         return
 104     end
 105
 106     local tag = capi.tag({ name = "Revelation" })
 107     tag.screen = screen
 108
 109     layout_fn(tag, #clients)
 110
 111     local function restore()
 112         for k, cl in pairs(tag:clients()) do
 113             -- Clear revelation tag
 114             local tags = cl:tags()
 115             if tags[tag] then
 116                 tags[tags[tag]] = nil
 117             end
 118             cl:tags(tags)
 119             -- Restore client mouse bindings
 120             cl:buttons(data[cl])
 121             data[cl] = nil
 122         end
 123         tag.screen = nil
 124         capi.keygrabber.stop()
 125     end
 126
 127     for k, c in pairs(clients) do
 128         data[c] = c:buttons()
 129         c:buttons({ button({}, 1, selectfn(restore)) })
 130     end
 131     tag:clients(clients)
 132     awful.tag.viewonly(tag)
 133     capi.keygrabber.run(keyboardhandler(restore))
 134 end