Fix skewed timeline for family events

src/family_tree_view_timeline.py

@@ -545,6 +545,16 @@ def draw_timeline(self, event_and_ref_list, timeline_canvas, event_labels):
             except ZeroDivisionError:
                 y_time_rel = 0
             y_time = y_time_rel * timeline_height + self.timeline_top_margin
+            if self.obj_type == "F":
+                # y_time above goes progressively skewed for a family
+                # because the timeline attach points were calculated on the
+                # entire vertical span. For a family, they should be
+                # calculated on the span only from time 0 to the bottom.
+                y_time_bottom = canvas_height - self.timeline_bottom_margin
+                y_time_family_factor = (y_time_bottom - (zero_event_offset + self.timeline_top_margin)) / y_time_bottom # % of the timeline
+                y_time_temp = y_time - (zero_event_offset + self.timeline_top_margin)
+                y_time_temp = y_time_temp * y_time_family_factor # apply the factor with respect to the applicable span
+                y_time = y_time_temp + (zero_event_offset + self.timeline_top_margin)
 
             connect_to_previous = prev_y_time is not None and y_time - prev_y_time < 2*self.timeline_marker_radius