+
+
+/* Call this when a mouse-wheel click is detected.
+ Clicks act like horizontal or vertical drags.
+ Percent is the length of the drag as a percentage of the screen size.
+ Button is 'Button4' or 'Button5' (for the vertical wheel)
+ or 'Button5' or 'Button6' (for the horizontal wheel).
+ If `flip_p' is true, swap the horizontal and vertical axes.
+ */
+void
+gltrackball_mousewheel (trackball_state *ts,
+ int button, int percent, int flip_p)
+{
+ int up_p;
+ int horizontal_p;
+ int mx, my, move, scale;
+
+#ifdef HAVE_COCOA
+ flip_p = 0; /* MacOS has already handled this. */
+#endif
+
+ switch (button) {
+ case Button4: up_p = 1; horizontal_p = 0; break;
+ case Button5: up_p = 0; horizontal_p = 0; break;
+ case Button6: up_p = 1; horizontal_p = 1; break;
+ case Button7: up_p = 0; horizontal_p = 1; break;
+ default: abort(); break;
+ }
+
+ if (flip_p)
+ {
+ horizontal_p = !horizontal_p;
+ up_p = !up_p;
+ }
+
+ scale = mx = my = 1000;
+ move = (up_p
+ ? floor (scale * (1.0 - (percent / 100.0)))
+ : ceil (scale * (1.0 + (percent / 100.0))));
+ if (horizontal_p) mx = move;
+ else my = move;
+ gltrackball_start (ts, scale, scale, scale*2, scale*2);
+ gltrackball_track (ts, mx, my, scale*2, scale*2);
+}
+
+void
+gltrackball_get_quaternion (trackball_state *ts, float q[4])
+{
+ int i;
+ for (i=0; i<4; i++)
+ q[i] = ts->q[i];
+}
+
+
+/* A utility function for event-handler functions:
+ Handles the various motion and click events related to trackballs.
+ Returns True if the event was handled.
+ */
+Bool
+gltrackball_event_handler (XEvent *event,
+ trackball_state *ts,
+ int window_width, int window_height,
+ Bool *button_down_p)
+{
+ if (event->xany.type == ButtonPress &&
+ event->xbutton.button == Button1)
+ {
+ *button_down_p = True;
+ gltrackball_start (ts,
+ event->xbutton.x, event->xbutton.y,
+ window_width, window_height);
+ return True;
+ }
+ else if (event->xany.type == ButtonRelease &&
+ event->xbutton.button == Button1)
+ {
+ *button_down_p = False;
+ gltrackball_stop (ts);
+ return True;
+ }
+ else if (event->xany.type == ButtonPress &&
+ (event->xbutton.button == Button4 ||
+ event->xbutton.button == Button5 ||
+ event->xbutton.button == Button6 ||
+ event->xbutton.button == Button7))
+ {
+ gltrackball_mousewheel (ts, event->xbutton.button, 10,
+ !!event->xbutton.state);
+ return True;
+ }
+ else if (event->xany.type == MotionNotify &&
+ *button_down_p)
+ {
+ gltrackball_track (ts,
+ event->xmotion.x, event->xmotion.y,
+ window_width, window_height);
+ return True;
+ }
+
+ return False;
+}