+
+/************************************************************
+ * !!! This design is experimental and not yet fully implemented !!!!!!!!!!!!!
+ *
+ * AREA :
+ * Areas in tint2 are similar to widgets in a GUI.
+ * Graphical objects (panel, taskbar, task, systray, clock, ...) in tint2 'inherit' an Area class.
+ * Area is an abstract class of objects. It's at the begining of each object (&object == &area).
+ * Area manage the background and border drawing, size and padding.
+ *
+ * DATA ORGANISATION :
+ * tint2 define one panel per monitor. And each panel have a tree of Area (nodes).
+ * The root of the tree is Panel.Area. And task, clock, systray, taskbar,... are nodes.
+ *
+ * 'panel_items' parameter (in config) define the list and the order of nodes in tree's panel.
+ * 'panel_items = SC' define a panel with just Systray and Clock.
+ * So the root Panel.Area will have 2 childs (Systray and Clock).
+ *
+ * The tree allow to browse panel's objects from background to foreground and from left to right.
+ * The position of each node/Area depend on parent's position and brothers on the left.
+ *
+ * DRAWING EVENT :
+ * In the end, redrawing an object (like the clock) could come from an external event (date change)
+ * or from a layering event (size or position change).
+ *
+ * DRAWING LOOP :
+ * 1) browse tree and resize SIZE_BY_CONTENT node
+ * - children node are resized before its parent
+ * - if 'size' changed then 'redraw = 1' and 'resize = 1' on the parent
+ * 2) browse tree and resize SIZE_BY_LAYOUT node
+ * - parent node is resized before its children
+ * - if 'size' changed then 'redraw = 1' and 'resize = 1' on childs with SIZE_BY_LAYOUT
+ * 3) calculate posx of objects
+ * - parent's position is calculated before children's position
+ * - if 'position' changed then 'redraw = 1'
+ * 4) redraw needed objects
+ * - parent node is drawn before its children
+ *
+ * perhaps 2) and 3) can be merged...
+ * répartition entre niveau global et niveau local ??
+ * size_by_content peut-il modifier redraw=1 en cas de changement ? ou est ce géré par chaque composant ?
+ * size_by_layout peut-il modifier redraw ?
+ *
+ ************************************************************/
+
+