+ switch (mouse_mode) {
+ case MouseAudition:
+ if (_scrubbing) {
+
+ double delta;
+
+ if (scrubbing_direction == 0) {
+ /* first move */
+ session->request_locate (drag_info.current_pointer_frame, false);
+ session->request_transport_speed (0.1);
+ scrubbing_direction = 1;
+
+ } else {
+
+ if (last_scrub_x > drag_info.current_pointer_x) {
+
+ /* pointer moved to the left */
+
+ if (scrubbing_direction > 0) {
+
+ /* we reversed direction to go backwards */
+
+ scrub_reversals++;
+ scrub_reverse_distance += (int) (last_scrub_x - drag_info.current_pointer_x);
+
+ } else {
+
+ /* still moving to the left (backwards) */
+
+ scrub_reversals = 0;
+ scrub_reverse_distance = 0;
+
+ delta = 0.01 * (last_scrub_x - drag_info.current_pointer_x);
+ session->request_transport_speed (session->transport_speed() - delta);
+ }
+
+ } else {
+ /* pointer moved to the right */
+
+ if (scrubbing_direction < 0) {
+ /* we reversed direction to go forward */
+
+ scrub_reversals++;
+ scrub_reverse_distance += (int) (drag_info.current_pointer_x - last_scrub_x);
+
+ } else {
+ /* still moving to the right */
+
+ scrub_reversals = 0;
+ scrub_reverse_distance = 0;
+
+ delta = 0.01 * (drag_info.current_pointer_x - last_scrub_x);
+ session->request_transport_speed (session->transport_speed() + delta);
+ }
+ }
+
+ /* if there have been more than 2 opposite motion moves detected, or one that moves
+ back more than 10 pixels, reverse direction
+ */
+
+ if (scrub_reversals >= 2 || scrub_reverse_distance > 10) {
+
+ if (scrubbing_direction > 0) {
+ /* was forwards, go backwards */
+ session->request_transport_speed (-0.1);
+ scrubbing_direction = -1;
+ } else {
+ /* was backwards, go forwards */
+ session->request_transport_speed (0.1);
+ scrubbing_direction = 1;
+ }
+
+ scrub_reverse_distance = 0;
+ scrub_reversals = 0;
+ }
+ }
+
+ last_scrub_x = drag_info.current_pointer_x;
+ }
+
+ default:
+ break;
+ }
+
+