basics of row/col span for Canvas::Grid

2 files changed, 47 insertions, 20 deletions

diff --git a/libs/canvas/canvas/grid.h b/libs/canvas/canvas/grid.h
index c0afa4bdfa..36dac116eb 100644
--- a/libs/canvas/canvas/grid.h
+++ b/libs/canvas/canvas/grid.h
@@ -63,7 +63,14 @@ public:
 
 	void child_changed ();
   private:
-	typedef std::map<Item*,Duple> CoordsByItem;
+	struct ChildInfo {
+		double x;
+		double y;
+		double col_span;
+		double row_span;
+	};
+
+	typedef std::map<Item*,ChildInfo> CoordsByItem;
 	CoordsByItem coords_by_item;
 
 	Rectangle *bg;
diff --git a/libs/canvas/grid.cc b/libs/canvas/grid.cc
index f8fd0bcce4..15d57b4886 100644
--- a/libs/canvas/grid.cc
+++ b/libs/canvas/grid.cc
@@ -256,29 +256,29 @@ Grid::reposition_children ()
 
 			CoordsByItem::const_iterator c = coords_by_item.find (*i);
 
-			row_dimens[c->second.y] = max (row_dimens[c->second.y], bb.height());
-			col_dimens[c->second.x] = max (col_dimens[c->second.x]	, bb.width());
-		}
-	}
-
-	/* now sum the row and column widths, so that row_dimens is transformed
-	 * into the y coordinate of the upper left of each row, and col_dimens
-	 * is transformed into the x coordinate of the left edge of each
-	 * column.
-	 */
+			const double per_col_width = bb.width() / c->second.col_span;
+			const double per_row_height = bb.height() / c->second.row_span;
 
-	double current_top_edge = top_margin + top_padding;
+			/* set the width of each column spanned by this item
+			 */
 
-	for (uint32_t n = 0; n < max_row; ++n) {
-		if (row_dimens[n]) {
-			/* height defined for this row */
-			const double h = row_dimens[n]; /* save height */
-			row_dimens[n] = current_top_edge;
-			cerr << "row[" << n << "] @ " << row_dimens[n] << endl;
-			current_top_edge = current_top_edge + h + row_spacing;
+			for (int n = 0; n < (int) c->second.col_span; ++n) {
+				col_dimens[c->second.x + n] = max (col_dimens[c->second.x + n], per_col_width);
+			}
+			for (int n = 0; n < (int) c->second.row_span; ++n) {
+				row_dimens[c->second.y + n] = max (row_dimens[c->second.y + n], per_row_height);
+			}
 		}
 	}
 
+	/* now progressively sum the row and column widths, once we're done:
+	 *
+	 * col_dimens: transformed into the x coordinate of the left edge of each column.
+	 *
+	 * row_dimens: transformed into the y coordinate of the upper left of each row,
+	 *
+	 */
+
 	double current_right_edge = left_margin + left_padding;
 
 	for (uint32_t n = 0; n < max_col; ++n) {
@@ -291,6 +291,18 @@ Grid::reposition_children ()
 		}
 	}
 
+	double current_top_edge = top_margin + top_padding;
+
+	for (uint32_t n = 0; n < max_row; ++n) {
+		if (row_dimens[n]) {
+			/* height defined for this row */
+			const double h = row_dimens[n]; /* save height */
+			row_dimens[n] = current_top_edge;
+			cerr << "row[" << n << "] @ " << row_dimens[n] << endl;
+			current_top_edge = current_top_edge + h + row_spacing;
+		}
+	}
+
 	/* position each item at the upper left of its (row, col) coordinate,
 	 * given the width of all rows or columns before it.
 	 */
@@ -315,8 +327,16 @@ Grid::reposition_children ()
 void
 Grid::place (Item* i, double x, double y, double col_span, double row_span)
 {
+	ChildInfo ci;
+
 	add (i);
-	coords_by_item.insert (std::make_pair (i, Duple (x, y)));
+
+	ci.x = x;
+	ci.y = y;
+	ci.col_span = col_span;
+	ci.row_span = row_span;
+
+	coords_by_item.insert (std::make_pair (i, ci));
 	reposition_children ();
 }