output-item: Collapse the inheritance hierarchy into a single struct.

[pspp] / src / output / charts / boxplot-cairo.c

diff --git a/src/output/charts/boxplot-cairo.c b/src/output/charts/boxplot-cairo.c
index 041b4fabb8decb597bec804a7e6bcf83497a7d0c..8448b2d6c411d41431a91a99cf561700071d2a01 100644 (file)
--- a/src/output/charts/boxplot-cairo.c
+++ b/src/output/charts/boxplot-cairo.c
@@ -145,15 +145,17 @@ boxplot_draw_box (cairo_t *cr, const struct xrchart_geometry *geom,
 }
 
 void
-xrchart_draw_boxplot (const struct chart_item *chart_item, cairo_t *cr,
+xrchart_draw_boxplot (const struct chart *chart, cairo_t *cr,
                       struct xrchart_geometry *geom)
 {
-  const struct boxplot *boxplot = to_boxplot (chart_item);
+  const struct boxplot *boxplot = to_boxplot (chart);
   double box_width;
   size_t i;
 
-  xrchart_write_yscale (cr, geom, boxplot->y_min, boxplot->y_max);
-  xrchart_write_title (cr, geom, "%s", chart_item->title);
+  if (! xrchart_write_yscale (cr, geom, boxplot->y_min, boxplot->y_max))
+    return;
+
+  xrchart_write_title (cr, geom, "%s", chart->title);
 
   box_width = (geom->axis[SCALE_ABSCISSA].data_max - geom->axis[SCALE_ABSCISSA].data_min) / boxplot->n_boxes / 2.0;
   for (i = 0; i < boxplot->n_boxes; i++)