+ENTRYPOINT Bool
+stairs_handle_event (ModeInfo *mi, XEvent *event)
+{
+ stairsstruct *sp = &stairs[MI_SCREEN(mi)];
+
+ if (event->xany.type == ButtonPress &&
+ event->xbutton.button == Button1)
+ {
+ sp->button_down_p = True;
+ gltrackball_start (sp->trackball,
+ event->xbutton.x, event->xbutton.y,
+ MI_WIDTH (mi), MI_HEIGHT (mi));
+ return True;
+ }
+ else if (event->xany.type == ButtonRelease &&
+ event->xbutton.button == Button1)
+ {
+ sp->button_down_p = False;
+ 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 (sp->trackball, event->xbutton.button, 10,
+ !!event->xbutton.state);
+ return True;
+ }
+ else if (event->xany.type == MotionNotify &&
+ sp->button_down_p)
+ {
+ gltrackball_track (sp->trackball,
+ event->xmotion.x, event->xmotion.y,
+ MI_WIDTH (mi), MI_HEIGHT (mi));
+ return True;
+ }
+ else if (event->xany.type == KeyPress)
+ {
+ KeySym keysym;
+ char c = 0;
+ XLookupString (&event->xkey, &c, 1, &keysym, 0);
+ if (c == ' ')
+ {
+ gltrackball_reset (sp->trackball);
+ return True;
+ }
+ }
+
+ return False;
+}
+
+