def_layer 该如何设置？

chncgn

请高手翻译一下这是什么意思？该如何设置才好？
def_layer   为不同类型的项目指定缺省的层名。第一个
值字符串是层类型。第二个值字符串是层
名。

layer_3d_items,
layer_ae_driving_dim,
layer_all_detail_item
s,
layer_annotation_elem
ent,
layer_assem_member,
layer_assy_cut_feat,
layer_axis,
layer_axis_ent,
layer_chamfer_feat,
layer_comp_design_mod
el,
layer_comp_fixture,
layer_comp_workpiece,
layer_copy_geom_feat,
layer_corn_chamf_feat
,
layer_cosm_round_feat
, layer_cosm_sketch,
layer_csys,
layer_csys_ent,
layer_curve,
layer_curve_ent,
layer_cut_feat,
layer_datum,
layer_datum_plane,
layer_datum_point,
layer_detail_item,
layer_dgm_conn_comp,
layer_dgm_highway,
layer_dgm_rail,
layer_dgm_wire,
layer_dim,
layer_draft_constr,
layer_draft_dim,
layer_draft_dtm,
layer_draft_entity,
layer_draft_feat,
layer_draft_geom,
layer_draft_grp,
layer_draft_hidden,
layer_draft_others,
layer_draft_refdim,
layer_draft_xsec,
layer_driven_dim,
layer_dwg_table,
layer_ext_copy_geom_f
eat, layer_feature,
layer_geom_feat,
layer_gtol,
layer_hole_feat,
layer_hole_thread,
layer_intchg_funct,
layer_intchg_simp,
layer_nogeom_feat,
layer_note,
layer_parameter_dim,
layer_part_refdim,
layer_poin

hacker_807

太复杂了点

chncgn

这个我也是看不懂，请高人解答，谢谢！