+ switch (ev->direction) {
+ case GDK_SCROLL_UP:
+ if (Keyboard::modifier_state_equals (ev->state, Keyboard::ScrollZoomVerticalModifier)) {
+ /* See Editor::_stepping_axis_view for notes on this hack */
+ Editor& e = dynamic_cast<Editor&> (_editor);
+ if (!e.stepping_axis_view ()) {
+ e.set_stepping_axis_view (this);
+ }
+ e.stepping_axis_view()->step_height (false);
+ return true;
+ }
+ break;
+
+ case GDK_SCROLL_DOWN:
+ if (Keyboard::modifier_state_equals (ev->state, Keyboard::ScrollZoomVerticalModifier)) {
+ /* See Editor::_stepping_axis_view for notes on this hack */
+ Editor& e = dynamic_cast<Editor&> (_editor);
+ if (!e.stepping_axis_view ()) {
+ e.set_stepping_axis_view (this);
+ }
+ e.stepping_axis_view()->step_height (true);
+ return true;
+ }
+ break;
+
+ default:
+ /* no handling for left/right, yet */
+ break;
+ }
+