+/**
+ *
+ */
+guint8
+vik_map_source_get_zoom_min (VikMapSource * self)
+{
+ VikMapSourceClass *klass;
+ g_return_val_if_fail (self != NULL, 0);
+ g_return_val_if_fail (VIK_IS_MAP_SOURCE (self), 0);
+ klass = VIK_MAP_SOURCE_GET_CLASS(self);
+ g_return_val_if_fail (klass->get_zoom_min != NULL, 0);
+ return (*klass->get_zoom_min)(self);
+}
+
+/**
+ *
+ */
+guint8
+vik_map_source_get_zoom_max (VikMapSource * self)
+{
+ VikMapSourceClass *klass;
+ g_return_val_if_fail (self != NULL, 18);
+ g_return_val_if_fail (VIK_IS_MAP_SOURCE (self), 18);
+ klass = VIK_MAP_SOURCE_GET_CLASS(self);
+ g_return_val_if_fail (klass->get_zoom_max != NULL, 18);
+ return (*klass->get_zoom_max)(self);
+}
+
+/**
+ *
+ */
+gdouble
+vik_map_source_get_lat_max (VikMapSource * self)
+{
+ VikMapSourceClass *klass;
+ g_return_val_if_fail (self != NULL, 90.0);
+ g_return_val_if_fail (VIK_IS_MAP_SOURCE (self), 90.0);
+ klass = VIK_MAP_SOURCE_GET_CLASS(self);
+ g_return_val_if_fail (klass->get_lat_max != NULL, 90.0);
+ return (*klass->get_lat_max)(self);
+}
+
+/**
+ *
+ */
+gdouble
+vik_map_source_get_lat_min (VikMapSource * self)
+{
+ VikMapSourceClass *klass;
+ g_return_val_if_fail (self != NULL, -90.0);
+ g_return_val_if_fail (VIK_IS_MAP_SOURCE (self), -90.0);
+ klass = VIK_MAP_SOURCE_GET_CLASS(self);
+ g_return_val_if_fail (klass->get_lat_min != NULL, -90.0);
+ return (*klass->get_lat_min)(self);
+}
+
+/**
+ *
+ */
+gdouble
+vik_map_source_get_lon_max (VikMapSource * self)
+{
+ VikMapSourceClass *klass;
+ g_return_val_if_fail (self != NULL, 180.0);
+ g_return_val_if_fail (VIK_IS_MAP_SOURCE (self), 180.0);
+ klass = VIK_MAP_SOURCE_GET_CLASS(self);
+ g_return_val_if_fail (klass->get_lon_max != NULL, 180.0);
+ return (*klass->get_lon_max)(self);
+}
+
+/**
+ *
+ */
+gdouble
+vik_map_source_get_lon_min (VikMapSource * self)
+{
+ VikMapSourceClass *klass;
+ g_return_val_if_fail (self != NULL, -180.0);
+ g_return_val_if_fail (VIK_IS_MAP_SOURCE (self), -180.0);
+ klass = VIK_MAP_SOURCE_GET_CLASS(self);
+ g_return_val_if_fail (klass->get_lon_min != NULL, -180.0);
+ return (*klass->get_lon_min)(self);
+}
+
+/**
+ * vik_map_source_get_file_extension:
+ * @self: the VikMapSource of interest.
+ *
+ * Returns the file extension of files held on disk.
+ * Typically .png but may be .jpg or whatever the user defines
+ *
+ */
+const gchar *
+vik_map_source_get_file_extension (VikMapSource * self)
+{
+ VikMapSourceClass *klass;
+ g_return_val_if_fail (self != NULL, NULL);
+ g_return_val_if_fail (VIK_IS_MAP_SOURCE (self), NULL);
+ klass = VIK_MAP_SOURCE_GET_CLASS(self);
+
+ g_return_val_if_fail (klass->get_file_extension != NULL, NULL);
+
+ return (*klass->get_file_extension)(self);
+}
+