guint16 params_count, gchar **groups, guint8 groups_count,
gboolean (*setparam) (gpointer,guint16,VikLayerParamData,gpointer),
gpointer pass_along1, gpointer pass_along2,
guint16 params_count, gchar **groups, guint8 groups_count,
gboolean (*setparam) (gpointer,guint16,VikLayerParamData,gpointer),
gpointer pass_along1, gpointer pass_along2,