wimp/window_frame

A WIMP-style window frame.

........................  <─ Resize sensor
.┌────────────────────┐.
.│      Window  [o][x]│.  <─ Window frame header, drag sensor and control buttons
.├────────────────────┤.
.│'''''''''''''''''''^│.  <- ': Viewport #1
.│'                 '║│.
.│'                 '║│.
.│'                 '║│.
.│'                 '║│.
.│'''''''''''''''''''v│.
.│<═════════════════> │.  <─ Optional scroll bars
.└────────────────────┘.
........................