This is the data common to both the model and view classes.
if the item can take the keyboard focus.
the #cairo_fill_rule_t setting specifying the fill rule used for the clip path.
an array of #GooCanvasPathCommand specifying the clip path of the item, or %NULL.
if the item is static.
if the item has its own style, rather than using its parent's.
the #GooCanvasPointerEvents setting specifying the events the item should receive.
the style to draw with.
the item's tooltip.
the transformation matrix of the item, or %NULL.
the #GooCanvasItemVisibility setting specifying whether the item is visible, invisible, or visible above a given canvas scale setting.
the threshold scale setting at which to show the item
visibility setting is set to %VISIBLE_ABOVE_THRESHOLD).