void gis_viewer_set_location(GisViewer *viewer, gdouble lat, gdouble lon, gdouble elev);
void gis_viewer_get_location(GisViewer *viewer, gdouble *lat, gdouble *lon, gdouble *elev);
-void gis_viewer_pan (GisViewer *viewer, gdouble lat, gdouble lon, gdouble elev);
-void gis_viewer_zoom (GisViewer *viewer, gdouble scale);
+void gis_viewer_pan(GisViewer *self, gdouble forward, gdouble sideways, gdouble up);
+void gis_viewer_zoom(GisViewer *viewer, gdouble scale);
void gis_viewer_set_rotation(GisViewer *viewer, gdouble x, gdouble y, gdouble z);
void gis_viewer_get_rotation(GisViewer *viewer, gdouble *x, gdouble *y, gdouble *z);