diff --git a/src/actions.c b/src/actions.c
index 6a6ba6ac..deee4153 100644
--- a/src/actions.c
+++ b/src/actions.c
@@ -578,15 +578,15 @@ void enable_layers(void)
 {
   int i;
   char tmp[50];
-  xctx->n_active_layers = 0;
+  n_active_layers = 0;
   for(i = 0; i< cadlayers; i++) {
     my_snprintf(tmp, S(tmp), "enable_layer(%d)",i);
     if(tclgetvar(tmp)[0] == '0') enable_layer[i] = 0;
     else {
       enable_layer[i] = 1;
       if(i>=7) {
-        xctx->active_layer[xctx->n_active_layers] = i;
-        xctx->n_active_layers++;
+        active_layer[n_active_layers] = i;
+        n_active_layers++;
       }
     }
   }
diff --git a/src/callback.c b/src/callback.c
index 8bae3e08..473bf14f 100644
--- a/src/callback.c
+++ b/src/callback.c
@@ -460,8 +460,8 @@ int callback(int event, int mx, int my, KeySym key,
    }
    if(key == '$'  && ( state == ShiftMask) )            /* toggle pixmap  saving */
    {
-    draw_pixmap =!draw_pixmap;
-    if(draw_pixmap) tcleval("alert_ { enabling draw pixmap} {}");
+    xctx->draw_pixmap =!xctx->draw_pixmap;
+    if(xctx->draw_pixmap) tcleval("alert_ { enabling draw pixmap} {}");
     else tcleval("alert_ { disabling draw pixmap} {}");
     break;
    }
@@ -480,17 +480,17 @@ int callback(int event, int mx, int my, KeySym key,
    if(key == '='  && (state &ControlMask))              /* toggle fill rectangles */
    {
     int x;
-    xctx->fill_pattern++;
-    if(xctx->fill_pattern==3) xctx->fill_pattern=0;
+    fill_pattern++;
+    if(fill_pattern==3) fill_pattern=0;
 
-    if(xctx->fill_pattern==1) {
+    if(fill_pattern==1) {
      tcleval("alert_ { Stippled pattern fill} {}");
      for(x=0;x<cadlayers;x++) {
        if(fill_type[x]==1) XSetFillStyle(display,gcstipple[x],FillSolid);
        else XSetFillStyle(display,gcstipple[x],FillStippled);
      }
     }
-    else if(xctx->fill_pattern==2) {
+    else if(fill_pattern==2) {
      tcleval("alert_ { solid pattern fill} {}");
      for(x=0;x<cadlayers;x++)
       XSetFillStyle(display,gcstipple[x],FillSolid);
@@ -563,7 +563,7 @@ int callback(int event, int mx, int my, KeySym key,
    }
    if(key == XK_Escape )                        /* abort & redraw */
    {
-    no_draw = 0;
+    xctx->no_draw = 0;
     if(xctx->semaphore >= 2) break;
     tcleval("set constrained_move 0" );
     constrained_move=0;
@@ -1305,13 +1305,13 @@ int callback(int event, int mx, int my, KeySym key,
    }
    if(key=='>') {
      if(xctx->semaphore >= 2) break;
-     if(draw_single_layer< cadlayers-1) draw_single_layer++;
+     if(xctx->draw_single_layer< cadlayers-1) xctx->draw_single_layer++;
      draw();
      break;
    }
    if(key=='<') {
      if(xctx->semaphore >= 2) break;
-     if(draw_single_layer>=0 ) draw_single_layer--;
+     if(xctx->draw_single_layer>=0 ) xctx->draw_single_layer--;
      draw();
      break;
    }
diff --git a/src/check.c b/src/check.c
index 884b0730..ec2d2f70 100644
--- a/src/check.c
+++ b/src/check.c
@@ -55,7 +55,7 @@ void update_conn_cues(int draw_cues, int dr_win)
 
   hash_wires(); /* must be done also if wires==0 to clear wiretable */
   if(!xctx->wires) return;
-  if(!draw_dots) return;
+  if(!xctx->draw_dots) return;
   if(cadhalfdotsize*xctx->mooz<0.7) return;
   x1 = X_TO_XSCHEM(xctx->areax1);
   y1 = Y_TO_XSCHEM(xctx->areay1);
@@ -104,10 +104,10 @@ void update_conn_cues(int draw_cues, int dr_win)
       /* optimization when editing small areas (detailed zoom)  of a huge schematic */
       if(LINE_OUTSIDE(wire[i].x1, wire[i].y1,
                       wire[i].x2, wire[i].y2, x1, y1, x2, y2)) continue;
-      if( wire[i].end1 >1 ) { /* 20150331 draw_dots */
+      if( wire[i].end1 >1 ) {
         filledarc(WIRELAYER, ADD, wire[i].x1, wire[i].y1, cadhalfdotsize, 0, 360);
       }
-      if( wire[i].end2 >1 ) { /* 20150331 draw_dots */
+      if( wire[i].end2 >1 ) {
         filledarc(WIRELAYER, ADD, wire[i].x2, wire[i].y2, cadhalfdotsize, 0, 360);
       }
     }
diff --git a/src/draw.c b/src/draw.c
index 4b2872d8..67701ce0 100644
--- a/src/draw.c
+++ b/src/draw.c
@@ -76,7 +76,7 @@ void print_image()
   #endif
   save_draw_grid = draw_grid;
   draw_grid=0;
-  draw_pixmap=1;
+  xctx->draw_pixmap=1;
   draw();
   #ifdef __unix__
   XpmWriteFileFromPixmap(display, "plot.xpm", xctx->save_pixmap,0, NULL ); /* .gz ???? */
@@ -95,7 +95,7 @@ void print_image()
   #endif
   my_strncpy(xctx->plotfile,"", S(xctx->plotfile));
   draw_grid=save_draw_grid;
-  draw_pixmap=1;
+  xctx->draw_pixmap=1;
 }
 
 #if HAS_CAIRO==1
@@ -244,7 +244,7 @@ void draw_string(int layer, int what, const char *str, short rot, short flip, in
       /*fprintf(errfp, "cairo_draw_string(): tt=%s, longest line: %d\n", tt, longest_line); */
       if(draw_window) cairo_draw_string_line(xctx->cairo_ctx, tt, x, y, rot, flip,
          lineno, fext.height, fext.ascent, fext.descent, llength, no_of_lines, longest_line);
-      if(draw_pixmap) cairo_draw_string_line(xctx->cairo_save_ctx, tt, x, y, rot, flip,
+      if(xctx->draw_pixmap) cairo_draw_string_line(xctx->cairo_save_ctx, tt, x, y, rot, flip,
          lineno, fext.height, fext.ascent, fext.descent, llength, no_of_lines, longest_line);
       lineno++;
       if(c==0) break;
@@ -664,12 +664,12 @@ void drawgrid()
   x = xctx->xorigin*xctx->mooz; y = xctx->yorigin*xctx->mooz;
   if(y>xctx->areay1 && y < xctx->areay2) {
     if(draw_window) XDrawLine(display, xctx->window, gc[GRIDLAYER],xctx->areax1+1,(int)y, xctx->areax2-1, (int)y);
-    if(draw_pixmap)
+    if(xctx->draw_pixmap)
       XDrawLine(display, xctx->save_pixmap, gc[GRIDLAYER],xctx->areax1+1,(int)y, xctx->areax2-1, (int)y);
   }
   if(x>xctx->areax1 && x < xctx->areax2) {
     if(draw_window) XDrawLine(display, xctx->window, gc[GRIDLAYER],(int)x,xctx->areay1+1, (int)x, xctx->areay2-1);
-    if(draw_pixmap)
+    if(xctx->draw_pixmap)
       XDrawLine(display, xctx->save_pixmap, gc[GRIDLAYER],(int)x,xctx->areay1+1, (int)x, xctx->areay2-1);
   }
   tmp = floor((xctx->areay1+1)/delta)*delta-fmod(-xctx->yorigin*xctx->mooz,delta);
@@ -683,7 +683,7 @@ void drawgrid()
             XDrawPoints(display,xctx->window,gc[GRIDLAYER],xctx->gridpoint,i,CoordModeOrigin);
           }
         }
-        if(draw_pixmap) {
+        if(xctx->draw_pixmap) {
           if(big_grid_points) {
             XDrawSegments(display,xctx->save_pixmap,gc[GRIDLAYER],xctx->biggridpoint,i);
           } else {
@@ -710,7 +710,7 @@ void drawgrid()
       XDrawPoints(display,xctx->window,gc[GRIDLAYER],xctx->gridpoint,i,CoordModeOrigin);
     }
   }
-  if(draw_pixmap) {
+  if(xctx->draw_pixmap) {
     if(big_grid_points) {
       XDrawSegments(display,xctx->save_pixmap,gc[GRIDLAYER],xctx->biggridpoint,i);
     } else {
@@ -741,13 +741,13 @@ void drawline(int c, int what, double linex1, double liney1, double linex2, doub
   {
 #ifdef __unix__
    if(draw_window) XDrawSegments(display, xctx->window, gc[c], rr,i);
-   if(draw_pixmap)
+   if(xctx->draw_pixmap)
      XDrawSegments(display, xctx->save_pixmap, gc[c], rr,i);
 #else
     for (j = 0; j < i; ++j) {
       if (draw_window)
         XDrawLine(display, xctx->window, gc[c], rr[j].x1, rr[j].y1, rr[j].x2, rr[j].y2);
-      if (draw_pixmap)
+      if (xctx->draw_pixmap)
         XDrawLine(display, xctx->save_pixmap, gc[c], rr[j].x1, rr[j].y1, rr[j].x2, rr[j].y2);
     }
 #endif
@@ -782,7 +782,7 @@ void drawline(int c, int what, double linex1, double liney1, double linex2, doub
      XSetLineAttributes (display, gc[c], INT_WIDTH(xctx->lw), xDashType, CapButt, JoinBevel);
    }
    if(draw_window) XDrawLine(display, xctx->window, gc[c], x1, y1, x2, y2);
-   if(draw_pixmap)
+   if(xctx->draw_pixmap)
     XDrawLine(display, xctx->save_pixmap, gc[c], x1, y1, x2, y2);
    if(dash) {
      XSetLineAttributes (display, gc[c], INT_WIDTH(xctx->lw), LineSolid, CapRound, JoinRound);
@@ -807,7 +807,7 @@ void drawline(int c, int what, double linex1, double liney1, double linex2, doub
      XSetLineAttributes (display, gc[c], INT_BUS_WIDTH(xctx->lw), LineSolid, CapRound, JoinRound);
    }
    if(draw_window) XDrawLine(display, xctx->window, gc[c], x1, y1, x2, y2);
-   if(draw_pixmap) XDrawLine(display, xctx->save_pixmap, gc[c], x1, y1, x2, y2);
+   if(xctx->draw_pixmap) XDrawLine(display, xctx->save_pixmap, gc[c], x1, y1, x2, y2);
    XSetLineAttributes (display, gc[c], INT_WIDTH(xctx->lw), LineSolid, CapRound , JoinRound);
   }
  }
@@ -816,12 +816,12 @@ void drawline(int c, int what, double linex1, double liney1, double linex2, doub
  {
 #ifdef __unix__
   if(draw_window) XDrawSegments(display, xctx->window, gc[c], rr,i);
-  if(draw_pixmap) XDrawSegments(display, xctx->save_pixmap, gc[c], rr,i);
+  if(xctx->draw_pixmap) XDrawSegments(display, xctx->save_pixmap, gc[c], rr,i);
 #else
    for (j = 0; j < i; ++j) {
      if (draw_window)
        XDrawLine(display, xctx->window, gc[c], rr[j].x1, rr[j].y1, rr[j].x2, rr[j].y2);
-     if (draw_pixmap)
+     if (xctx->draw_pixmap)
        XDrawLine(display, xctx->save_pixmap, gc[c], rr[j].x1, rr[j].y1, rr[j].x2, rr[j].y2);
    }
 #endif
@@ -1012,7 +1012,7 @@ void filledarc(int c, int what, double x, double y, double r, double a, double b
   if(i>=CADDRAWBUFFERSIZE)
   {
    if(draw_window) XFillArcs(display, xctx->window, gc[c], xarc,i);
-   if(draw_pixmap) XFillArcs(display, xctx->save_pixmap, gc[c], xarc,i);
+   if(xctx->draw_pixmap) XFillArcs(display, xctx->save_pixmap, gc[c], xarc,i);
    i=0;
   }
   xx1=X_TO_SCREEN(x-r);
@@ -1049,14 +1049,14 @@ void filledarc(int c, int what, double x, double y, double r, double a, double b
   if( rectclip(xctx->areax1,xctx->areay1,xctx->areax2,xctx->areay2,&x1,&y1,&x2,&y2) )
   {
    if(draw_window) XFillArc(display, xctx->window, gc[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
-   if(draw_pixmap) XFillArc(display, xctx->save_pixmap, gc[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
+   if(xctx->draw_pixmap) XFillArc(display, xctx->save_pixmap, gc[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
   }
  }
  else if(what & START) i=0;
  else if((what & END) && i)
  {
   if(draw_window) XFillArcs(display, xctx->window, gc[c], xarc,i);
-  if(draw_pixmap) XFillArcs(display, xctx->save_pixmap, gc[c], xarc,i);
+  if(xctx->draw_pixmap) XFillArcs(display, xctx->save_pixmap, gc[c], xarc,i);
   i=0;
  }
 }
@@ -1077,7 +1077,7 @@ void drawarc(int c, int what, double x, double y, double r, double a, double b,
   if(i>=CADDRAWBUFFERSIZE)
   {
    if(draw_window) XDrawArcs(display, xctx->window, gc[c], xarc,i);
-   if(draw_pixmap) XDrawArcs(display, xctx->save_pixmap, gc[c], xarc,i);
+   if(xctx->draw_pixmap) XDrawArcs(display, xctx->save_pixmap, gc[c], xarc,i);
    i=0;
   }
   xx1=X_TO_SCREEN(x-r);
@@ -1126,15 +1126,15 @@ void drawarc(int c, int what, double x, double y, double r, double a, double b,
    if(draw_window) {
      XDrawArc(display, xctx->window, gc[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
    }
-   if(draw_pixmap) {
+   if(xctx->draw_pixmap) {
      XDrawArc(display, xctx->save_pixmap, gc[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
    }
 
-   if(xctx->fill_pattern && fill_type[c]){
+   if(fill_pattern && fill_type[c]){
      if(arc_fill) {
        if(draw_window)
          XFillArc(display, xctx->window, gcstipple[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
-       if(draw_pixmap)
+       if(xctx->draw_pixmap)
          XFillArc(display, xctx->save_pixmap, gcstipple[c], xx1, yy1, xx2-xx1, yy2-yy1, a*64, b*64);
      }
    }
@@ -1147,7 +1147,7 @@ void drawarc(int c, int what, double x, double y, double r, double a, double b,
  else if((what & END) && i)
  {
   if(draw_window) XDrawArcs(display, xctx->window, gc[c], xarc,i);
-  if(draw_pixmap) XDrawArcs(display, xctx->save_pixmap, gc[c], xarc,i);
+  if(xctx->draw_pixmap) XDrawArcs(display, xctx->save_pixmap, gc[c], xarc,i);
   i=0;
  }
 }
@@ -1160,7 +1160,7 @@ void filledrect(int c, int what, double rectx1,double recty1,double rectx2,doubl
  double x1,y1,x2,y2;
 
  if(!has_x) return;
- if(!xctx->fill_pattern || !fill_type[c]) return;
+ if(!fill_pattern || !fill_type[c]) return;
  if(what & NOW)
  {
   x1=X_TO_SCREEN(rectx1);
@@ -1173,7 +1173,7 @@ void filledrect(int c, int what, double rectx1,double recty1,double rectx2,doubl
    if(draw_window) XFillRectangle(display, xctx->window, gcstipple[c], (int)x1, (int)y1,
     (unsigned int)x2 - (unsigned int)x1,
     (unsigned int)y2 - (unsigned int)y1);
-   if(draw_pixmap)
+   if(xctx->draw_pixmap)
      XFillRectangle(display, xctx->save_pixmap,gcstipple[c],  (int)x1, (int)y1,
       (unsigned int)x2 - (unsigned int)x1,
       (unsigned int)y2 - (unsigned int)y1);
@@ -1185,7 +1185,7 @@ void filledrect(int c, int what, double rectx1,double recty1,double rectx2,doubl
   if(i>=CADDRAWBUFFERSIZE)
   {
    if(draw_window) XFillRectangles(display, xctx->window, gcstipple[c], r,i);
-   if(draw_pixmap)
+   if(xctx->draw_pixmap)
      XFillRectangles(display, xctx->save_pixmap, gcstipple[c], r,i);
    i=0;
   }
@@ -1206,7 +1206,7 @@ void filledrect(int c, int what, double rectx1,double recty1,double rectx2,doubl
  else if((what & END) && i)
  {
   if(draw_window) XFillRectangles(display, xctx->window, gcstipple[c], r,i);
-  if(draw_pixmap) XFillRectangles(display, xctx->save_pixmap, gcstipple[c], r,i);
+  if(xctx->draw_pixmap) XFillRectangles(display, xctx->save_pixmap, gcstipple[c], r,i);
   i=0;
  }
 }
@@ -1312,12 +1312,12 @@ void drawpolygon(int c, int what, double *x, double *y, int points, int poly_fil
     XSetLineAttributes (display, gc[c], INT_WIDTH(xctx->lw), xDashType, CapButt, JoinBevel);
   }
   if(draw_window) XDrawLines(display, xctx->window, gc[c], p, points, CoordModeOrigin);
-  if(draw_pixmap)
+  if(xctx->draw_pixmap)
     XDrawLines(display, xctx->save_pixmap, gc[c], p, points, CoordModeOrigin);
-  if(xctx->fill_pattern && fill_type[c]){
+  if(fill_pattern && fill_type[c]){
     if(poly_fill && (x[0] == x[points-1]) && (y[0] == y[points-1])) {
       if(draw_window) XFillPolygon(display, xctx->window, gcstipple[c], p, points, Polygontype, CoordModeOrigin);
-      if(draw_pixmap)
+      if(xctx->draw_pixmap)
          XFillPolygon(display, xctx->save_pixmap, gcstipple[c], p, points, Polygontype, CoordModeOrigin);
     }
   }
@@ -1378,7 +1378,7 @@ void drawrect(int c, int what, double rectx1,double recty1,double rectx2,double
    if(draw_window) XDrawRectangle(display, xctx->window, gc[c], (int)x1, (int)y1,
     (unsigned int)x2 - (unsigned int)x1,
     (unsigned int)y2 - (unsigned int)y1);
-   if(draw_pixmap)
+   if(xctx->draw_pixmap)
    {
     XDrawRectangle(display, xctx->save_pixmap, gc[c], (int)x1, (int)y1,
     (unsigned int)x2 - (unsigned int)x1,
@@ -1395,7 +1395,7 @@ void drawrect(int c, int what, double rectx1,double recty1,double rectx2,double
   if(i>=CADDRAWBUFFERSIZE)
   {
    if(draw_window) XDrawRectangles(display, xctx->window, gc[c], r,i);
-   if(draw_pixmap)
+   if(xctx->draw_pixmap)
      XDrawRectangles(display, xctx->save_pixmap, gc[c], r,i);
    i=0;
   }
@@ -1416,7 +1416,7 @@ void drawrect(int c, int what, double rectx1,double recty1,double rectx2,double
  else if((what & END) && i)
  {
   if(draw_window) XDrawRectangles(display, xctx->window, gc[c], r,i);
-  if(draw_pixmap) XDrawRectangles(display, xctx->save_pixmap, gc[c], r,i);
+  if(xctx->draw_pixmap) XDrawRectangles(display, xctx->save_pixmap, gc[c], r,i);
   i=0;
  }
 }
@@ -1485,10 +1485,10 @@ void draw(void)
  #if HAS_CAIRO==1
  char *textfont;
  #endif
- if(no_draw) return;
+ if(xctx->no_draw) return;
  rebuild_selected_array();
  if(has_x) {
-    if(draw_pixmap)
+    if(xctx->draw_pixmap)
       XFillRectangle(display, xctx->save_pixmap, gc[BACKLAYER], xctx->areax1, xctx->areay1,
                      xctx->areaw, xctx->areah);
     if(draw_window) 
@@ -1509,7 +1509,7 @@ void draw(void)
         struct iterator_ctx ctx;
         dbg(3, "draw(): check4\n");
         for(c=0;c<cadlayers;c++) {
-          if(draw_single_layer!=-1 && c != draw_single_layer) continue;
+          if(xctx->draw_single_layer!=-1 && c != xctx->draw_single_layer) continue;
 
           if(enable_layer[c]) for(i=0;i<xctx->lines[c];i++) {
             xLine *l = &xctx->line[c][i];
@@ -1559,7 +1559,7 @@ void draw(void)
           drawrect(c, END, 0.0, 0.0, 0.0, 0.0, 0);
           drawline(c, END, 0.0, 0.0, 0.0, 0.0, 0);
         }
-        if(draw_single_layer==-1 || draw_single_layer==WIRELAYER) {
+        if(xctx->draw_single_layer==-1 || xctx->draw_single_layer==WIRELAYER) {
           if(use_hash) init_wire_iterator(&ctx, x1, y1, x2, y2);
           else i = -1;
           while(1) {
@@ -1583,7 +1583,7 @@ void draw(void)
           filledrect(WIRELAYER, END, 0.0, 0.0, 0.0, 0.0);
           drawline(WIRELAYER, END, 0.0, 0.0, 0.0, 0.0, 0);
         }
-        if(draw_single_layer ==-1 || draw_single_layer==TEXTLAYER) {
+        if(xctx->draw_single_layer ==-1 || xctx->draw_single_layer==TEXTLAYER) {
           for(i=0;i<xctx->texts;i++)
           {
             textlayer = xctx->text[i].layer;
diff --git a/src/globals.c b/src/globals.c
index 99ee3a02..61b80966 100644
--- a/src/globals.c
+++ b/src/globals.c
@@ -163,7 +163,6 @@ int en_hilight_conn_inst = 0;
 
 int help=0; /* help option set to global scope, printing help is deferred */
             /* when configuration ~/.schem has been read 20140406 */
-int no_draw=0;
 FILE *errfp;
 char *filename=NULL; /* filename given on cmdline */
 char user_conf_dir[PATH_MAX];
@@ -184,32 +183,29 @@ int debug_var=-10;  /* will be set to 0 in xinit.c */
 int tcp_port = 0;
 int do_print=0;
 int no_readline=0;
-int draw_pixmap=1; /* use pixmap for double buffer */
 int draw_window=0;
 int text_svg=1; /* use <text> svg element for text instead of xschem's internal vector font */
 int text_ps=1;  /* use ps font for text instead of xschem's internal vector font */
 double cadhalfdotsize = CADHALFDOTSIZE;
 unsigned int color_index[256]; /* layer color lookup table */
-int max_undo=MAX_UNDO;
-int draw_dots=1;
-int draw_single_layer=-1;
 int yyparse_error = 0;
 int *enable_layer;
+int n_active_layers = 0;
+int *active_layer;
 int screendepth;
-int *fill_type; /* for every layer: 0: no fill, 1, solid fill, 2: stipple fill */
 char **color_array;
+int *fill_type;
+int fill_pattern = 1;
+double color_dim = 0.0;
 char *xschem_executable=NULL;
 double *character[256]; /* array or per-char coordinates of xschem internal vector font */
 Tcl_Interp *interp;
 int do_netlist=0;  /* set by process_options if user wants netllist from cmdline */
 int do_simulation=0;
 int do_waves=0;
-int netlist_count=0; /* netlist counter incremented at any cell being netlisted */
 char bus_char[3] = {0, 0, 0};
 int constrained_move = 0;
-double color_dim=0.0;
 int batch_mode = 0; /* no tcl console if set; batch mode */
-int show_erc=1;
 
 /* following data is relative to the current schematic */
 Xschem_ctx *xctx;
diff --git a/src/hilight.c b/src/hilight.c
index 1511b2ae..7f15019f 100644
--- a/src/hilight.c
+++ b/src/hilight.c
@@ -97,22 +97,22 @@ void free_hilight_hash(void) /* remove the whole hash table  */
 }
 
 /* by default: 
- * xctx->active_layer[0] = 7
- * xctx->active_layer[1] = 8
- * xctx->active_layer[2] = 10  if 9 is disabled it is skipped
+ * active_layer[0] = 7
+ * active_layer[1] = 8
+ * active_layer[2] = 10  if 9 is disabled it is skipped
  * ...
  * if a layer is disabled (not viewable) it is skipped
- * xctx->n_active_layers is the total number of layers for hilights.
- * standard xschem conf: cadlayers=22, xctx->n_active_layers=15 if no disabled layers.
+ * n_active_layers is the total number of layers for hilights.
+ * standard xschem conf: cadlayers=22, n_active_layers=15 if no disabled layers.
  */
 int get_color(int value)
 {
   int x;
 
   if(value < 0) return (-value) % cadlayers ;
-  if(xctx->n_active_layers) {
-    x = value%(xctx->n_active_layers);
-    return xctx->active_layer[x];
+  if(n_active_layers) {
+    x = value%(n_active_layers);
+    return active_layer[x];
   } else {
     return cadlayers > 5 ? 5 : cadlayers -1; /* desperate attempt to return a decent color */
   }
@@ -121,7 +121,7 @@ int get_color(int value)
 
 void incr_hilight_color(void)
 {
-  xctx->hilight_color = (xctx->hilight_color + 1) % (xctx->n_active_layers * cadlayers);
+  xctx->hilight_color = (xctx->hilight_color + 1) % (n_active_layers * cadlayers);
 }
 
 /* print all highlight signals which are not ports (in/out/inout). */
@@ -1444,7 +1444,7 @@ void logic_set(int value, int num)
   if(!xctx->simdata.valid) create_simdata();
   rebuild_selected_array();
   newval = value;
-  if(!no_draw && !big) {
+  if(!xctx->no_draw && !big) {
     calc_drawing_bbox(&boundbox, 2);
     bbox(START, 0.0 , 0.0 , 0.0 , 0.0);
     bbox(ADD, boundbox.x1, boundbox.y1, boundbox.x2, boundbox.y2);
@@ -1480,13 +1480,13 @@ void logic_set(int value, int num)
     propagate_logic();
     propagate_hilights(1, 0, XINSERT);
   }
-  if(!no_draw && !big) {
+  if(!xctx->no_draw && !big) {
     calc_drawing_bbox(&boundbox, 2);
     bbox(ADD, boundbox.x1, boundbox.y1, boundbox.x2, boundbox.y2);
     bbox(SET , 0.0 , 0.0 , 0.0 , 0.0);
   }
   draw();
-  if(!no_draw && !big) bbox(END , 0.0 , 0.0 , 0.0 , 0.0);
+  if(!xctx->no_draw && !big) bbox(END , 0.0 , 0.0 , 0.0 , 0.0);
   tcleval("if { [info exists gaw_fd] } {close $gaw_fd; unset gaw_fd}\n");
 }
 
@@ -1692,17 +1692,17 @@ void draw_hilight_net(int on_window)
        drawline(get_color(entry->value), NOW,
           xctx->wire[i].x1, xctx->wire[i].y1, xctx->wire[i].x2, xctx->wire[i].y2, 0);
      if(cadhalfdotsize*xctx->mooz>=0.7) {
-       if( xctx->wire[i].end1 >1 ) { /* 20150331 draw_dots */
+       if( xctx->wire[i].end1 >1 ) {
          filledarc(get_color(entry->value), NOW, xctx->wire[i].x1, xctx->wire[i].y1, cadhalfdotsize, 0, 360);
        }
-       if( xctx->wire[i].end2 >1 ) { /* 20150331 draw_dots */
+       if( xctx->wire[i].end2 >1 ) {
          filledarc(get_color(entry->value), NOW, xctx->wire[i].x2, xctx->wire[i].y2, cadhalfdotsize, 0, 360);
        }
      }
    }
  }
  for(c=0;c<cadlayers;c++) {
-   if(draw_single_layer!=-1 && c != draw_single_layer) continue;
+   if(xctx->draw_single_layer!=-1 && c != xctx->draw_single_layer) continue;
    if(use_hash) init_inst_iterator(&ctx, x1, y1, x2, y2);
    else i = -1;
    while(1) {
diff --git a/src/in_memory_undo.c b/src/in_memory_undo.c
index 2e06e7ce..ac325b1d 100644
--- a/src/in_memory_undo.c
+++ b/src/in_memory_undo.c
@@ -203,7 +203,7 @@ void push_undo(void)
     initialized=1;
     init_undo();
   }
-  slot = xctx->cur_undo_ptr%max_undo;
+  slot = xctx->cur_undo_ptr%MAX_UNDO;
 
   my_strdup(173, &uslot[slot].gptr, xctx->schvhdlprop);
   my_strdup(174, &uslot[slot].vptr, xctx->schverilogprop);
@@ -308,7 +308,7 @@ void push_undo(void)
 
   xctx->cur_undo_ptr++;
   xctx->head_undo_ptr = xctx->cur_undo_ptr;
-  xctx->tail_undo_ptr = xctx->head_undo_ptr <= max_undo? 0: xctx->head_undo_ptr-max_undo;
+  xctx->tail_undo_ptr = xctx->head_undo_ptr <= MAX_UNDO? 0: xctx->head_undo_ptr-MAX_UNDO;
 }
 
 
@@ -333,7 +333,7 @@ void pop_undo(int redo)
     if(xctx->cur_undo_ptr<=0) return; /* check undo tail */
     xctx->cur_undo_ptr--;
   }
-  slot = xctx->cur_undo_ptr%max_undo;
+  slot = xctx->cur_undo_ptr%MAX_UNDO;
   clear_drawing();
   unselect_all();
   my_strdup(198, &xctx->schvhdlprop, uslot[slot].gptr);
diff --git a/src/netlist.c b/src/netlist.c
index 98e409a3..58d12aaf 100644
--- a/src/netlist.c
+++ b/src/netlist.c
@@ -276,7 +276,7 @@ void hash_inst_pin(int what, int i, int j)
         xctx->inst[i].name, j, prop_ptr);
     statusmsg(str,2);
     tcleval("wm deiconify .infotext"); /* critical error: force ERC window showing */
-    if(!netlist_count) {
+    if(!xctx->netlist_count) {
       xctx->inst[i].color = -PINLAYER;
       xctx->hilight_nets=1;
     }
@@ -448,7 +448,7 @@ static void signal_short( char *n1, char *n2)
    dbg(1, "signal_short(): signal_short: shorted: %s - %s", n1, n2);
    statusmsg(str,2);
    tcleval("wm deiconify .infotext"); /* critical error: force ERC window showing */
-   if(!netlist_count) {
+   if(!xctx->netlist_count) {
       bus_hilight_lookup(n1, xctx->hilight_color, XINSERT);
       if(incr_hilight) incr_hilight_color();
       bus_hilight_lookup(n2, xctx->hilight_color, XINSERT);
@@ -655,8 +655,8 @@ void prepare_netlist_structs(int for_netlist)
   else delete_netlist_structs();
   xctx->simdata.valid = 0;
   dbg(1, "prepare_netlist_structs(): extraction\n");
-  if(netlist_count == 0 ) startlevel = xctx->currsch;
-  print_erc =  netlist_count == 0 || startlevel < xctx->currsch;
+  if(xctx->netlist_count == 0 ) startlevel = xctx->currsch;
+  print_erc =  xctx->netlist_count == 0 || startlevel < xctx->currsch;
 
   if (for_netlist>0) {
     my_snprintf(nn, S(nn), "-----------%s", xctx->sch[xctx->currsch]);
diff --git a/src/node_hash.c b/src/node_hash.c
index 33ce4b2c..21b081ac 100644
--- a/src/node_hash.c
+++ b/src/node_hash.c
@@ -304,7 +304,6 @@ void traverse_node_hash()
  struct node_hashentry *entry;
  char str[2048]; /* 20161122 overflow safe */
 
- if(!show_erc)return;
  for(i=0;i<HASHSIZE;i++)
  {
   entry = xctx->node_table[i];
@@ -314,14 +313,14 @@ void traverse_node_hash()
      if(entry->d.out + entry->d.inout + entry->d.in == 1)
      {
        my_snprintf(str, S(str), "open net: %s", entry->token);
-       if(!netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
+       if(!xctx->netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
        if(incr_hilight) incr_hilight_color();
        statusmsg(str,2);
      }
      else if(entry->d.out ==0  && entry->d.inout == 0)
      {
        my_snprintf(str, S(str), "undriven node: %s", entry->token);
-       if(!netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
+       if(!xctx->netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
        if(incr_hilight) incr_hilight_color();
        statusmsg(str,2);
        tcleval("wm deiconify .infotext"); /* critical error: force ERC window showing */
@@ -329,21 +328,21 @@ void traverse_node_hash()
      else if(entry->d.out >=2 && entry->d.port>=0)  /*  era d.port>=2   03102001 */
      {
        my_snprintf(str, S(str), "shorted output node: %s", entry->token);
-       if(!netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
+       if(!xctx->netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
        if(incr_hilight) incr_hilight_color();
        statusmsg(str,2);
      }
      else if(entry->d.in ==0 && entry->d.inout == 0)
      {
        my_snprintf(str, S(str), "node: %s goes nowhere", entry->token);
-       if(!netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
+       if(!xctx->netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
        if(incr_hilight) incr_hilight_color();
        statusmsg(str,2);
      }
      else if(entry->d.out >=2 && entry->d.inout == 0 && entry->d.port>=0)  /*  era d.port>=2   03102001 */
      {
        my_snprintf(str, S(str), "shorted output node: %s", entry->token);
-       if(!netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
+       if(!xctx->netlist_count) bus_hilight_lookup(entry->token, xctx->hilight_color, XINSERT_NOREPLACE);
        if(incr_hilight) incr_hilight_color();
        statusmsg(str,2);
      }
diff --git a/src/psprint.c b/src/psprint.c
index 9a72aaf1..2e02cc99 100644
--- a/src/psprint.c
+++ b/src/psprint.c
@@ -118,7 +118,7 @@ static void set_ps_colors(unsigned int pixel)
 
 static void ps_xdrawarc(int layer, int fillarc, double x, double y, double r, double a, double b)
 {
- if(xctx->fill_pattern && fillarc)
+ if(fill_pattern && fillarc)
    fprintf(fd, "%g %g %g %g %g A %g %g LT C F S\n", x, y, r, -a, -a-b, x, y);
  else
    fprintf(fd, "%g %g %g %g %g A S\n", x, y, r, -a, -a-b);
@@ -140,7 +140,7 @@ static void ps_xfillrectange(int layer, double x1, double y1, double x2,
                   double y2)
 {
  fprintf(fd, "%g %g %g %g R\n", x1,y1,x2-x1,y2-y1);
- if( (fill_type[layer] == 1) && xctx->fill_pattern) {
+ if( (fill_type[layer] == 1) && fill_pattern) {
    fprintf(fd, "%g %g %g %g RF\n", x1,y1,x2-x1,y2-y1);
    /* fprintf(fd,"fill\n"); */
  }
@@ -174,7 +174,7 @@ static void ps_drawpolygon(int c, int what, double *x, double *y, int points, in
     if(i==0) fprintf(fd, "NP\n%g %g MT\n", xx, yy);
     else fprintf(fd, "%g %g LT\n", xx, yy);
   }
-  if(xctx->fill_pattern && fill_type[c] && poly_fill) {
+  if(fill_pattern && fill_type[c] && poly_fill) {
     fprintf(fd, "C F S\n");
   } else {
     fprintf(fd, "S\n");
@@ -852,10 +852,10 @@ void create_ps(char **psfile, int what)
       y2 = Y_TO_XSCHEM(xctx->areay2);
       for(init_wire_iterator(&ctx, x1, y1, x2, y2); ( wireptr = wire_iterator_next(&ctx) ) ;) {
         i = wireptr->n;
-        if( xctx->wire[i].end1 >1 ) { /* 20150331 draw_dots */
+        if( xctx->wire[i].end1 >1 ) {
           ps_drawarc(WIRELAYER, 1, xctx->wire[i].x1, xctx->wire[i].y1, cadhalfdotsize, 0, 360, 0);
         }
-        if( xctx->wire[i].end2 >1 ) { /* 20150331 draw_dots */
+        if( xctx->wire[i].end2 >1 ) {
           ps_drawarc(WIRELAYER, 1, xctx->wire[i].x2, xctx->wire[i].y2, cadhalfdotsize, 0, 360, 0);
         }
       }
diff --git a/src/save.c b/src/save.c
index 65c3abef..747b6aee 100644
--- a/src/save.c
+++ b/src/save.c
@@ -1118,7 +1118,7 @@ void delete_undo(void)
   int i;
   char diff_name[PATH_MAX]; /* overflow safe 20161122 */
 
-  for(i=0; i<max_undo; i++) {
+  for(i=0; i<MAX_UNDO; i++) {
     my_snprintf(diff_name, S(diff_name), "%s/undo%d",xctx->undo_dirname, i);
     xunlink(diff_name);
   }
@@ -1149,7 +1149,7 @@ void push_undo(void)
 
 
     #if HAS_POPEN==1
-    my_snprintf(diff_name, S(diff_name), "gzip --fast -c > %s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%max_undo);
+    my_snprintf(diff_name, S(diff_name), "gzip --fast -c > %s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%MAX_UNDO);
     fd = popen(diff_name,"w");
     if(!fd) {
       fprintf(errfp, "push_undo(): failed to open write pipe %s\n", diff_name);
@@ -1157,7 +1157,7 @@ void push_undo(void)
       return;
     }
     #elif HAS_PIPE==1
-    my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%max_undo);
+    my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%MAX_UNDO);
     pipe(pd);
     if((pid = fork()) ==0) {                                    /* child process */
       static char f[PATH_MAX] = "";
@@ -1186,7 +1186,7 @@ void push_undo(void)
     close(pd[0]);                                       /* close read side of pipe */
     fd=fdopen(pd[1],"w");
     #else /* uncompressed undo */
-    my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%max_undo);
+    my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%MAX_UNDO);
     fd = fopen(diff_name,"w");
     if(!fd) {
       fprintf(errfp, "push_undo(): failed to open undo file %s\n", diff_name);
@@ -1197,7 +1197,7 @@ void push_undo(void)
     write_xschem_file(fd);
     xctx->cur_undo_ptr++;
     xctx->head_undo_ptr = xctx->cur_undo_ptr;
-    xctx->tail_undo_ptr = xctx->head_undo_ptr <= max_undo? 0: xctx->head_undo_ptr-max_undo;
+    xctx->tail_undo_ptr = xctx->head_undo_ptr <= MAX_UNDO? 0: xctx->head_undo_ptr-MAX_UNDO;
     #if HAS_POPEN==1
     pclose(fd);
     #elif HAS_PIPE==1
@@ -1243,7 +1243,7 @@ void pop_undo(int redo)
   unselect_all();
 
   #if HAS_POPEN==1
-  my_snprintf(diff_name, S(diff_name), "gzip -d -c %s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%max_undo);
+  my_snprintf(diff_name, S(diff_name), "gzip -d -c %s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%MAX_UNDO);
   fd=popen(diff_name, "r");
   if(!fd) {
     fprintf(errfp, "pop_undo(): failed to open read pipe %s\n", diff_name);
@@ -1251,7 +1251,7 @@ void pop_undo(int redo)
     return;
   }
   #elif HAS_PIPE==1
-  my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%max_undo);
+  my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%MAX_UNDO);
   pipe(pd);
   if((pid = fork())==0) {                                     /* child process */
     static char f[PATH_MAX] = "";
@@ -1277,7 +1277,7 @@ void pop_undo(int redo)
   close(pd[1]);                                       /* close write side of pipe */
   fd=fdopen(pd[0],"r");
   #else /* uncompressed undo */
-  my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%max_undo);
+  my_snprintf(diff_name, S(diff_name), "%s/undo%d", xctx->undo_dirname, xctx->cur_undo_ptr%MAX_UNDO);
   fd=fopen(diff_name, "r");
   if(!fd) {
     fprintf(errfp, "pop_undo(): failed to open read pipe %s\n", diff_name);
diff --git a/src/scheduler.c b/src/scheduler.c
index 2ba02309..84ec7502 100644
--- a/src/scheduler.c
+++ b/src/scheduler.c
@@ -629,7 +629,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
          Tcl_SetResult(interp, "0",TCL_STATIC);
      }
      else if(!strcmp(argv[2],"no_draw")) {
-       if( no_draw != 0 )
+       if( xctx->no_draw != 0 )
          Tcl_SetResult(interp, "1",TCL_STATIC);
        else
          Tcl_SetResult(interp, "0",TCL_STATIC);
@@ -2183,7 +2183,7 @@ int xschem(ClientData clientdata, Tcl_Interp *interp, int argc, const char * arg
       }
       else if(!strcmp(argv[2],"no_draw")) {
         int s = atoi(argv[3]);
-        no_draw=s;
+        xctx->no_draw=s;
       }
       else if(!strcmp(argv[2],"hide_symbols")) {
         int s = atoi(argv[3]);
diff --git a/src/spice_netlist.c b/src/spice_netlist.c
index 48b47078..e1fdc3ff 100644
--- a/src/spice_netlist.c
+++ b/src/spice_netlist.c
@@ -135,7 +135,7 @@ void global_spice_netlist(int global)  /* netlister driver */
    bus_char[0] = str_tmp[0];
    bus_char[1] = str_tmp[1];
  }
- netlist_count=0;
+ xctx->netlist_count=0;
  my_snprintf(netl_filename, S(netl_filename), "%s/.%s_%d", 
    netlist_dir, skip_dir(xctx->sch[xctx->currsch]), getpid());
  dbg(1, "global_spice_netlist(): opening %s for writing\n",netl_filename);
@@ -235,7 +235,7 @@ void global_spice_netlist(int global)  /* netlister driver */
   }
  }
 
- netlist_count++;
+ xctx->netlist_count++;
 
  if(xctx->schprop && xctx->schprop[0]) {
    if(first == 0) fprintf(fd,"**** begin user architecture code\n");
@@ -384,7 +384,7 @@ void global_spice_netlist(int global)  /* netlister driver */
  }
  my_free(946, &type);
  my_free(947, &place);
- netlist_count = 0;
+ xctx->netlist_count = 0;
 }
 
 static char *model_name_result = NULL;
@@ -460,7 +460,7 @@ void spice_block_netlist(FILE *fd, int i)
 
   spice_stop ? load_schematic(0,filename, 0) : load_schematic(1,filename, 0);
   spice_netlist(fd, spice_stop);  /* 20111113 added spice_stop */
-  netlist_count++;
+  xctx->netlist_count++;
 
   if(xctx->schprop && xctx->schprop[0]) {
     fprintf(fd,"**** begin user architecture code\n");
@@ -523,8 +523,8 @@ void spice_netlist(FILE *fd, int spice_stop )
  
      if( type && !IS_LABEL_OR_PIN(type) ) {
        /* already done in global_spice_netlist */
-       if(!strcmp(type,"netlist_commands") && netlist_count==0) continue;
-       if(netlist_count &&
+       if(!strcmp(type,"netlist_commands") && xctx->netlist_count==0) continue;
+       if(xctx->netlist_count &&
           !strcmp(get_tok_value(xctx->inst[i].prop_ptr, "only_toplevel", 0), "true")) continue;
        if(!strcmp(type,"netlist_commands")) {
          fprintf(fd,"**** begin user architecture code\n");
@@ -546,7 +546,7 @@ void spice_netlist(FILE *fd, int spice_stop )
     }
     my_free(952, &type);
   }
-  if(!spice_stop && !netlist_count) redraw_hilights(0); /* draw_hilight_net(1); */
+  if(!spice_stop && !xctx->netlist_count) redraw_hilights(0); /* draw_hilight_net(1); */
 }
 
 /* calculate the hash function relative to string s */
diff --git a/src/svgdraw.c b/src/svgdraw.c
index 40d6f74b..53fbea27 100644
--- a/src/svgdraw.c
+++ b/src/svgdraw.c
@@ -756,10 +756,10 @@ void svg_draw(void)
         if(xctx->hilight_nets && (entry=bus_hilight_lookup( xctx->wire[i].node, 0, XLOOKUP))) {
           color = get_color(entry->value);
         }
-        if( xctx->wire[i].end1 >1 ) { /* 20150331 draw_dots */
+        if( xctx->wire[i].end1 >1 ) {
           svg_drawcircle(color, 1, xctx->wire[i].x1, xctx->wire[i].y1, cadhalfdotsize, 0, 360);
         }
-        if( xctx->wire[i].end2 >1 ) { /* 20150331 draw_dots */
+        if( xctx->wire[i].end2 >1 ) {
           svg_drawcircle(color, 1, xctx->wire[i].x2, xctx->wire[i].y2, cadhalfdotsize, 0, 360);
         }
       }
diff --git a/src/tedax_netlist.c b/src/tedax_netlist.c
index 5f6d1450..e4658893 100644
--- a/src/tedax_netlist.c
+++ b/src/tedax_netlist.c
@@ -46,7 +46,7 @@ void global_tedax_netlist(int global)  /* netlister driver */
    bus_char[0] = str_tmp[0];
    bus_char[1] = str_tmp[1];
  }
- netlist_count=0;
+ xctx->netlist_count=0;
  my_snprintf(netl_filename, S(netl_filename), "%s/.%s_%d", 
    netlist_dir, skip_dir(xctx->sch[xctx->currsch]), getpid());
  fd=fopen(netl_filename, "w");
@@ -73,7 +73,7 @@ void global_tedax_netlist(int global)  /* netlister driver */
  fprintf(fd,"tEDAx v1\nbegin netlist v1 %s\n", skip_dir( xctx->sch[xctx->currsch]) );
 
  tedax_netlist(fd, 0);
- netlist_count++;
+ xctx->netlist_count++;
 
  /*fprintf(fd,"**** begin user architecture code\n"); */
  /*if(xctx->schprop && xctx->schprop[0]) fprintf(fd, "%s\n", xctx->schprop); */
@@ -144,7 +144,7 @@ void global_tedax_netlist(int global)  /* netlister driver */
   tcleval(tcl_cmd_netlist);
  }
  if(!debug_var) xunlink(netl_filename);
- netlist_count = 0;
+ xctx->netlist_count = 0;
 }
 
 
@@ -187,7 +187,7 @@ void tedax_block_netlist(FILE *fd, int i)
   fprintf(fd, "\n");
   load_schematic(1,filename, 0);
   tedax_netlist(fd, tedax_stop);
-  netlist_count++;
+  xctx->netlist_count++;
 
   if(xctx->schprop && xctx->schprop[0]) {
     fprintf(fd,"#**** begin user architecture code\n");
@@ -231,8 +231,8 @@ void tedax_netlist(FILE *fd, int tedax_stop )
 
      if( type && !IS_LABEL_OR_PIN(type) ) {
        /* already done in global_tedax_netlist */
-       if(!strcmp(type,"netlist_commands") && netlist_count==0) continue;
-       if(netlist_count &&
+       if(!strcmp(type,"netlist_commands") && xctx->netlist_count==0) continue;
+       if(xctx->netlist_count &&
           !strcmp(get_tok_value(xctx->inst[i].prop_ptr, "only_toplevel", 0), "true")) continue;
        if(!strcmp(type,"netlist_commands")) {
          fprintf(fd,"#**** begin user architecture code\n");
@@ -245,7 +245,7 @@ void tedax_netlist(FILE *fd, int tedax_stop )
     }
     my_free(967, &type);
   }
-  if(!tedax_stop && !netlist_count) redraw_hilights(0); /* draw_hilight_net(1); */
+  if(!tedax_stop && !xctx->netlist_count) redraw_hilights(0); /* draw_hilight_net(1); */
 }
 
 
diff --git a/src/token.c b/src/token.c
index 38d8fef3..bf03b69b 100644
--- a/src/token.c
+++ b/src/token.c
@@ -1598,7 +1598,7 @@ int print_spice_element(FILE *fd, int inst)
   }
   no_of_pins= (xctx->inst[inst].ptr+ xctx->sym)->rects[PINLAYER];
   s=format;
-  dbg(1, "print_spice_element(): name=%s, format=%s netlist_count=%d\n",name,format, netlist_count);
+  dbg(1, "print_spice_element(): name=%s, format=%s xctx->netlist_count=%d\n",name,format, xctx->netlist_count);
   /* begin parsing format string */
   while(1)
   {
@@ -1988,7 +1988,7 @@ void print_tedax_element(FILE *fd, int inst)
  }
  if(format) {
   s=format;
-  dbg(1, "print_tedax_element(): name=%s, tedax_format=%s netlist_count=%d\n",name,format, netlist_count);
+  dbg(1, "print_tedax_element(): name=%s, tedax_format=%s xctx->netlist_count=%d\n",name,format, xctx->netlist_count);
   /* begin parsing format string */
   while(1)
   {
@@ -2346,7 +2346,7 @@ const char *net_name(int i, int j, int *multip, int hash_prefix_unnamed_net, int
                  i, j, xctx->inst[i].instname ) ;
      statusmsg(errstr,2);
      tcleval("wm deiconify .infotext"); /* critical error: force ERC window showing */
-     if(!netlist_count) {
+     if(!xctx->netlist_count) {
        xctx->inst[i].color = -PINLAYER;
        xctx->hilight_nets=1;
      }
@@ -2390,7 +2390,7 @@ void print_vhdl_primitive(FILE *fd, int inst) /* netlist  primitives, 20071217 *
  }
  no_of_pins= (xctx->inst[inst].ptr+ xctx->sym)->rects[PINLAYER];
  s=format;
- dbg(1, "print_vhdl_primitive(): name=%s, format=%s netlist_count=%d\n",name,format, netlist_count);
+ dbg(1, "print_vhdl_primitive(): name=%s, format=%s xctx->netlist_count=%d\n",name,format, xctx->netlist_count);
 
  fprintf(fd, "---- start primitive ");
  lab=expandlabel(name, &tmp);
@@ -2564,7 +2564,7 @@ void print_verilog_primitive(FILE *fd, int inst) /* netlist switch level primiti
   }
   no_of_pins= (xctx->inst[inst].ptr+ xctx->sym)->rects[PINLAYER];
   s=format;
-  dbg(1, "print_verilog_primitive(): name=%s, format=%s netlist_count=%d\n",name,format, netlist_count);
+  dbg(1, "print_verilog_primitive(): name=%s, format=%s xctx->netlist_count=%d\n",name,format, xctx->netlist_count);
 
   fprintf(fd, "---- start primitive ");
   lab=expandlabel(name, &tmp);
diff --git a/src/verilog_netlist.c b/src/verilog_netlist.c
index bdac85f1..207f6db0 100644
--- a/src/verilog_netlist.c
+++ b/src/verilog_netlist.c
@@ -47,7 +47,7 @@ void global_verilog_netlist(int global)  /* netlister driver */
    if(save_ok == -1) return;
  }
  free_hash(subckt_table);
- netlist_count=0;
+ xctx->netlist_count=0;
  /* top sch properties used for library use declarations and type definitions */
  /* to be printed before any entity declarations */
 
@@ -240,7 +240,7 @@ void global_verilog_netlist(int global)  /* netlister driver */
 
  dbg(1, "global_verilog_netlist(): netlisting  top level\n");
  verilog_netlist(fd, 0);
- netlist_count++;
+ xctx->netlist_count++;
  fprintf(fd,"---- begin user architecture code\n");
 
  for(i=0;i<xctx->instances;i++) {
@@ -347,7 +347,7 @@ void global_verilog_netlist(int global)  /* netlister driver */
  my_free(1076, &port_value);
  my_free(1077, &tmp_string);
  my_free(1078, &type);
- netlist_count = 0;
+ xctx->netlist_count = 0;
 }
 
 
@@ -469,7 +469,7 @@ void verilog_block_netlist(FILE *fd, int i)
 
   dbg(1, "verilog_block_netlist():       netlisting %s\n", skip_dir( xctx->sch[xctx->currsch]));
   verilog_netlist(fd, verilog_stop);
-  netlist_count++;
+  xctx->netlist_count++;
   fprintf(fd,"---- begin user architecture code\n");
   for(l=0;l<xctx->instances;l++) {
     if( strcmp(get_tok_value(xctx->inst[l].prop_ptr,"verilog_ignore",0),"true")==0 ) continue;
@@ -477,7 +477,7 @@ void verilog_block_netlist(FILE *fd, int i)
     if(!strcmp(get_tok_value( (xctx->inst[l].ptr+ xctx->sym)->prop_ptr, "verilog_ignore",0 ), "true") ) {
       continue;
     }
-    if(netlist_count &&
+    if(xctx->netlist_count &&
       !strcmp(get_tok_value(xctx->inst[l].prop_ptr, "only_toplevel", 0), "true")) continue;
 
     my_strdup(569, &type,(xctx->inst[l].ptr+ xctx->sym)->type);
@@ -553,5 +553,5 @@ void verilog_netlist(FILE *fd , int verilog_stop)
    my_free(1084, &type);
  }
  dbg(1, "verilog_netlist():       end\n");
- if(!verilog_stop && !netlist_count) redraw_hilights(0); /*draw_hilight_net(1); */
+ if(!verilog_stop && !xctx->netlist_count) redraw_hilights(0); /*draw_hilight_net(1); */
 }
diff --git a/src/vhdl_netlist.c b/src/vhdl_netlist.c
index f746fb72..11682a00 100644
--- a/src/vhdl_netlist.c
+++ b/src/vhdl_netlist.c
@@ -49,7 +49,7 @@ void global_vhdl_netlist(int global)  /* netlister driver */
    save_ok = save_schematic(xctx->sch[xctx->currsch]);
    if(save_ok == -1) return;
  }
- netlist_count=0;
+ xctx->netlist_count=0;
  free_hash(subckt_table);
  my_snprintf(netl_filename, S(netl_filename), "%s/.%s_%d", 
    netlist_dir, skip_dir(xctx->sch[xctx->currsch]), getpid());
@@ -324,7 +324,7 @@ void global_vhdl_netlist(int global)  /* netlister driver */
    override_netlist_type(-1); /* restore to netlist_dir default */
    if(debug_var==0) xunlink(netl_filename);
  }
- netlist_count++;
+ xctx->netlist_count++;
 
  /* preserve current level instance flags before descending hierarchy for netlisting, restore later */
  stored_flags = my_calloc(151, xctx->instances, sizeof(unsigned int));
@@ -401,7 +401,7 @@ void global_vhdl_netlist(int global)  /* netlister driver */
  my_free(1089, &sig_type);
  my_free(1090, &type);
  my_free(1091, &port_value);
- netlist_count = 0;
+ xctx->netlist_count = 0;
 }
 
 
@@ -595,7 +595,7 @@ void  vhdl_block_netlist(FILE *fd, int i)
     if(!strcmp(get_tok_value( (xctx->inst[l].ptr+ xctx->sym)->prop_ptr, "vhdl_ignore",0 ), "true") ) {
       continue;
     }
-    if(netlist_count &&
+    if(xctx->netlist_count &&
       !strcmp(get_tok_value(xctx->inst[l].prop_ptr, "only_toplevel", 0), "true")) continue;
 
     my_strdup(601, &type,(xctx->inst[l].ptr+ xctx->sym)->type);
@@ -614,7 +614,7 @@ void  vhdl_block_netlist(FILE *fd, int i)
     override_netlist_type(-1); /* restore to netlist_dir default */
     if(debug_var==0) xunlink(netl_filename);
   }
-  netlist_count++;
+  xctx->netlist_count++;
   my_free(1094, &sig_type);
   my_free(1095, &port_value);
   my_free(1096, &type);
@@ -705,5 +705,5 @@ void vhdl_netlist(FILE *fd , int vhdl_stop)
    my_free(1097, &type);
  }
  dbg(1, "vhdl_netlist():       end\n");
- if(!vhdl_stop && !netlist_count) redraw_hilights(0); /* draw_hilight_net(1); */
+ if(!vhdl_stop && !xctx->netlist_count) redraw_hilights(0); /* draw_hilight_net(1); */
 }
diff --git a/src/xinit.c b/src/xinit.c
index e45e5ab1..a0d49775 100644
--- a/src/xinit.c
+++ b/src/xinit.c
@@ -364,7 +364,6 @@ void free_xschem_data()
   for(i=0;i<CADMAXHIER;i++) my_free(1139, &xctx->sch_path[i]);
   my_free(1099, &xctx->gridpoint);
   my_free(1214, &xctx->biggridpoint);
-  my_free(1121, &xctx->active_layer);
   my_free(269, &xctx);
 }
 
@@ -523,13 +522,14 @@ void alloc_xschem_data()
   xctx->sel_array=my_calloc(619, xctx->maxsel, sizeof(Selected));
   xctx->biggridpoint=(XSegment*)my_calloc(1213, CADMAXGRIDPOINTS,sizeof(XSegment));
   xctx->gridpoint=(XPoint*)my_calloc(608, CADMAXGRIDPOINTS,sizeof(XPoint));
-  xctx->n_active_layers = 0;
-  xctx->active_layer=my_calloc(563, cadlayers, sizeof(int));
   xctx->enable_drill = 0;
   xctx->pending_fullzoom = 0;
   my_strncpy(xctx->hiersep, ".", S(xctx->hiersep));
   xctx->no_undo = 0;
-  xctx->fill_pattern = 1;
+  xctx->draw_single_layer = -1;
+  xctx->draw_dots = 1;
+  xctx->no_draw = 0;
+  xctx->draw_pixmap = 1;
 }
 
 void alloc_data()
@@ -538,10 +538,11 @@ void alloc_data()
 
  alloc_xschem_data();
  /* global context / graphic preferences/settings */
+ fill_type=my_calloc(640, cadlayers, sizeof(int));
+ active_layer=my_calloc(563, cadlayers, sizeof(int));
  color_array=my_calloc(637, cadlayers, sizeof(char*));
  gc=my_calloc(638, cadlayers, sizeof(GC));
  gcstipple=my_calloc(639, cadlayers, sizeof(GC));
- fill_type=my_calloc(640, cadlayers, sizeof(int));
  pixdata=my_calloc(641, cadlayers, sizeof(char*));
  for(i=0;i<cadlayers;i++)
  {
@@ -598,13 +599,14 @@ void xwin_exit(void)
    my_free(1101, &color_array[i]);
    my_free(1102, &pixdata[i]);
  }
- my_free(1120, &fill_type);
  my_free(1122, &pixdata);
  my_free(1123, &enable_layer);
  my_free(1135, &gc);
  my_free(1136, &gcstipple);
  my_free(1137, &color_array);
  my_free(1138, &tcl_command);
+ my_free(1121, &active_layer);
+ my_free(1120, &fill_type);
  clear_expandlabel_data();
  get_sym_template(NULL, NULL); /* clear static data in function */
  list_tokens(NULL, 0); /* clear static data in function */
diff --git a/src/xschem.h b/src/xschem.h
index 94bff077..5b70aa40 100644
--- a/src/xschem.h
+++ b/src/xschem.h
@@ -626,13 +626,15 @@ typedef struct {
   XSegment *biggridpoint;
   XPoint *gridpoint;
   char plotfile[PATH_MAX];
-  int *active_layer;
-  int n_active_layers;
   int enable_drill;
   int pending_fullzoom;
   char hiersep[20];
   int no_undo;
-  int fill_pattern; /*  fill rectangles */
+  int draw_single_layer;
+  int draw_dots;
+  int no_draw;
+  int draw_pixmap; /* pixmap used as 2nd buffer */
+  int netlist_count; /* netlist counter incremented at any cell being netlisted */
 } Xschem_ctx;
 
 struct Lcc { /* used for symbols containing schematics as instances (LCC, Local Custom Cell) */
@@ -758,7 +760,6 @@ extern int debug_var;
 extern int help;
 extern char *cad_icon[];
 extern int do_print;
-extern int no_draw;
 extern FILE *errfp;
 extern int no_readline;
 extern char *filename;
@@ -771,11 +772,16 @@ extern char *tcl_command;
 extern char tcl_script[PATH_MAX];
 extern int tcp_port;
 extern char **color_array;
+extern double color_dim; /* can not be put in Xctx unless all X11 colors are reset on window change */
 extern unsigned int color_index[];
+extern int n_active_layers; /* can not be put in Xctx, since it is bound to enable_layer[] */
+extern int *active_layer; /* can not be put in Xctx, since it is bound to enable_layer[] */
+extern int *fill_type; /* for every layer: 0: no fill, 1, solid fill, 2: stipple fill */
+                       /* can not be put in Xctx, since it sets XSetFillStyle */
+extern int fill_pattern; /*  fill rectangles, can not be put in Xctx, since it sets XSetFillStyle */
 extern int text_svg;
 extern int text_ps;
 extern double cadhalfdotsize;
-extern int draw_pixmap; /* pixmap used as 2nd buffer */
 extern XEvent xev;
 extern KeySym key;
 extern unsigned int button;
@@ -783,22 +789,14 @@ extern unsigned int state; /*  status of shift,ctrl etc.. */
 extern char *xschem_version_string;
 extern char initial_netlist_name[PATH_MAX];
 extern char bus_char[];
-extern int max_undo;
-extern int draw_dots;
-extern int draw_single_layer;
 extern int yyparse_error;
 extern char *xschem_executable;
-extern int screendepth;
-extern int *fill_type; /* 20171117 for every layer: 0: no fill, 1, solid fill, 2: stipple fill */
 extern Tcl_Interp *interp;
 extern double *character[256];
 extern int do_netlist;
 extern int do_simulation;
 extern int do_waves;
-extern int netlist_count;
 extern int quit;
-extern int show_erc;
-extern double color_dim;
 extern int batch_mode; /* no TCL console */
 extern const char fopen_read_mode[]; /* "r" on unix, "rb" on windows */
 
@@ -811,6 +809,7 @@ extern unsigned char pixdata_init[22][32];
 extern GC *gc, *gcstipple, gctiled;
 extern Display *display;
 extern int screen_number;
+extern int screendepth;
 extern XRectangle *rectangle;
 extern Pixmap cad_icon_pixmap, cad_icon_mask, *pixmap;
 extern XColor xcolor_array[];