Index: layertab.c
===================================================================
--- layertab.c	(nonexistent)
+++ layertab.c	(revision 33559)
@@ -0,0 +1,47 @@
+/*
+ *                            COPYRIGHT
+ *
+ *  pcb-rnd, interactive printed circuit board design
+ *  Copyright (C) 2020 Tibor 'Igor2' Palinkas
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ *  Contact:
+ *    Project page: http://repo.hu/projects/pcb-rnd
+ *    lead developer: http://repo.hu/projects/pcb-rnd/contact.html
+ *    mailing list: pcb-rnd (at) list.repo.hu (send "subscribe")
+ *
+ */
+
+
+typedef struct {
+	int id; /* in eagle */
+	pcb_layer_type_t lyt;
+	const char *purp;
+	const char *name;
+	int color;
+} eagle_layertab_t;
+
+static const eagle_layertab_t eagle_layertab[] = {
+
+	/* tDocu & bDocu are used for info used when designing, but not necessarily for
+	   exporting to Gerber i.e. package outlines that cross pads, or instructions.
+	   These layers within the silk groups will be needed when subc replaces elements
+	   since most Eagle packages use tDocu, bDocu for some of their artwork */
+	{51,  PCB_LYT_SILK | PCB_LYT_TOP,     NULL,    "tDocu",   14},
+	{52,  PCB_LYT_SILK | PCB_LYT_BOTTOM,  NULL,    "bDocu",   7},
+
+	{0}
+};
Index: read.c
===================================================================
--- read.c	(revision 33558)
+++ read.c	(revision 33559)
@@ -369,13 +369,10 @@
 	return 0;
 }
 
+#include "layertab.c"
+
 static pcb_layer_t *eagle_layer_get(read_state_t *st, eagle_layerid_t id, eagle_loc_t loc, void *obj)
 {
-	/* tDocu & bDocu are used for info used when designing, but not necessarily for
-	   exporting to Gerber i.e. package outlines that cross pads, or instructions.
-	   These layers within the silk groups will be needed when subc replaces elements
-	   since most Eagle packages use tDocu, bDocu for some of their artwork */
-
 	eagle_layer_t *ly = htip_get(&st->layers, id);
 	rnd_layer_id_t lid;
 	pcb_subc_t *subc = obj;
@@ -384,24 +381,18 @@
 
 	/* if more than 51 or 52 are considered useful, we could relax the test here: */
 	if ((ly == NULL) || (ly->lid < 0)) {
-		TODO("move this out to a separate function")
-		if (id == 51 || id == 52) {
+		const eagle_layertab_t *t;
+
+		for(t = eagle_layertab; t->id != 0; t++)
+			if (t->id == id)
+				break;
+
+		if (t->id == id) {
 				/* create docu on the first reference */
-			pcb_layer_type_t typ;
+			pcb_layer_type_t typ = t->lyt;
 			rnd_layergrp_id_t gid;
-			switch (id) {
-				case 51: /* = tDocu */
-					typ        = PCB_LYT_SILK | PCB_LYT_TOP;
-					ly->name   = "tDocu";
-					ly->color  = 14;
-					break;
-				default: /* i.e. 52 = bDocu: */
-					typ        = PCB_LYT_SILK | PCB_LYT_BOTTOM;
-					ly->name   = "bDocu";
-					ly->color  = 7;
-					break;
-			}
-
+			ly->name    = t->name;
+			ly->color   = t->color;
 			ly->fill    = 1;
 			ly->visible = 0;
 			ly->active  = 1;