Improve the handling of backgrounds and selection
in the presence of spanning columns.

Improve borders.  Somewhat more correct handling of double lined borders.
Still mostly wrong, but its a start.

2000-02-28  Jody Goldberg <jgoldberg@home.com>

	* src/expr.h : Move FunctionDefinition to
	* src/gnumeric.h : here.

	* src/cellspan.c (col_hash) : Use GPOINTER_TO_INT.
	(col_compare) : Ditto.
	(row_init_span) : Delete.
	(free_hash_value) : Renamed from free_hash_key.
	(cell_register_span) : Register all cells in a span, malloc a
	  CellSpanInfo to store a descriptor about the first and last cols.
	(assemble_unregister_span_list) : Delete.
	(span_remove) : New function for use by g_hash_table_foreach_remove.
	(cell_unregister_span) : Use g_hash_table_foreach_remove.
	(row_cell_get_displayed_at) : Adjust to new descriptor.
	(row_span_get) : New function.

	* src/cell.c (cell_calculate_span) : Renamed from cell_get_span.

	* src/cell-draw.c (cell_draw) : Do not draw backgrounds here.
	  Use new CellSpanInfo to avoid recomputing spans every time.
	(cell_is_blank) : Remove hack about treating empty strings as empty.

	* src/cellspan.h : New file.  Move span decls here.

	* src/item-grid.c (item_grid_draw) : Rework to correctly handle
	  backgrounds and borders for spanning columns.

2000-02-27  Jody Goldberg <jgoldberg@home.com>

	* src/cell.c (cell_is_blank) : Update.

	* src/border.c (style_border_draw) : Make somewhat more correct.
	  Still broken for non-top-left corners.

	* src/item-grid.c (item_grid_draw_border) : Ditto.
	(item_grid_draw_background) : Rename from item_grid_paint_empty_cell
	  handle spans more cleanly.
	(item_grid_draw_cell) : handle conditionals for displaying contents here.
	  Remove all handling of backgrounds.