-VikGpsLayer *vik_gps_layer_new ();
-void vik_gps_layer_add_layer ( VikGpsLayer *val, VikLayer *l );
-void vik_gps_layer_insert_layer ( VikGpsLayer *val, VikLayer *l, GtkTreeIter *replace_layer );
-void vik_gps_layer_move_layer ( VikGpsLayer *val, GtkTreeIter *child_iter, gboolean up );
-void vik_gps_layer_draw ( VikGpsLayer *val, gpointer data );
-void vik_gps_layer_free ( VikGpsLayer *val );
-void vik_gps_layer_clear ( VikGpsLayer *val );
-gboolean vik_gps_layer_delete ( VikGpsLayer *val, GtkTreeIter *iter );
-VikGpsLayer *vik_gps_layer_create (VikViewport *vp);