[Added New Feature]: New menu option 'Enable orthogonal wiring' is now accessible through the 'Options' menu. This option is kept ON-BY-DEFAULT and can be disabled through the menu, 'Shift+L'-keyboard-shortcut, or by editing the 'xschemrc' file to make xschem-editor revert back to it's old behavior - which was drawing wires in free-form mode (Unconstrained move). The functionality of the 'h' and 'v' keys are preserved, and they can still be used to force the editor to only draw horizontal or vertical wires respectively.

src/callback.c

@@ -87,7 +87,14 @@ void redraw_w_a_l_r_p_rubbers(void)
   if(xctx->ui_state & STARTWIRE) {
     if(xctx->constr_mv == 1) xctx->mousey_snap = xctx->my_double_save;
     if(xctx->constr_mv == 2) xctx->mousex_snap = xctx->mx_double_save;
-    new_wire(RUBBER, xctx->mousex_snap, xctx->mousey_snap);
+    if(tclgetboolvar("orthogonal_wiring")) {
+      new_wire(RUBBER|CLEAR, xctx->mousex_snap, xctx->mousey_snap);
+      int tmp_x2 = xctx->nl_x2 - xctx->nl_x1, tmp_y2 = xctx->nl_y2 - xctx->nl_y1;
+      if(tmp_x2*tmp_x2 > tmp_y2*tmp_y2) xctx->manhattan_lines = 1;
+      else xctx->manhattan_lines = 2;
+      new_wire(RUBBER, xctx->mousex_snap, xctx->mousey_snap);
+    }
+    else new_wire(RUBBER, xctx->mousex_snap, xctx->mousey_snap);
   }
   if(xctx->ui_state & STARTARC) {
     if(xctx->constr_mv == 1) xctx->mousey_snap = xctx->my_double_save;
@@ -3323,6 +3330,16 @@ int rstate; /* (reduced state, without ShiftMask) */
     place_net_label(0);
     break;
    }
+   if(key=='L' && rstate == 0) {                         /* toggle orthogonal routing */
+    if(tclgetboolvar("orthogonal_wiring")){
+      tclsetboolvar("orthogonal_wiring", 0);
+    } else {
+      tclsetboolvar("orthogonal_wiring", 1);
+    }
+    xctx->manhattan_lines = 0;
+    redraw_w_a_l_r_p_rubbers();
+    break;
+   }
    if(key=='F' && rstate == 0)                     /* flip */
    {
     if(xctx->ui_state & STARTMOVE) move_objects(FLIP,0,0,0);

src/xschem.tcl

@@ -7521,7 +7521,7 @@ set tctx::global_list {
   PDK_ROOT PDK SKYWATER_MODELS SKYWATER_STDCELLS 
   INITIALINSTDIR INITIALLOADDIR INITIALPROPDIR INITIALTEXTDIR XSCHEM_LIBRARY_PATH
   add_all_windows_drives auto_hilight auto_hilight_graph_nodes autofocus_mainwindow
-  autotrim_wires infix_wire bespice_listen_port big_grid_points bus_replacement_char cadgrid cadlayers
+  autotrim_wires infix_wire orthogonal_wiring bespice_listen_port big_grid_points bus_replacement_char cadgrid cadlayers
   cadsnap cairo_font_name cairo_font_scale change_lw color_ps tctx::colors compare_sch constr_mv
   copy_cell crosshair_layer custom_label_prefix custom_token dark_colors dark_colorscheme
   dark_gui_colorscheme delay_flag  dim_bg dim_value disable_unique_names
@@ -7942,7 +7942,7 @@ proc build_widgets { {topwin {} } } {
   global netlist_show flat_netlist split_files compare_sch intuitive_interface
   global draw_grid big_grid_points sym_txt change_lw incr_hilight symbol_width
   global cadsnap cadgrid draw_window toolbar_visible hide_symbols undo_type
-  global disable_unique_names persistent_command autotrim_wires infix_wire en_hilight_conn_inst
+  global disable_unique_names persistent_command autotrim_wires infix_wire orthogonal_wiring en_hilight_conn_inst
   global local_netlist_dir editor netlist_type netlist_dir spiceprefix initial_geometry
   if { $dark_gui_colorscheme} {
     set selectcolor white
@@ -8067,6 +8067,8 @@ proc build_widgets { {topwin {} } } {
      -selectcolor $selectcolor  -accelerator Y 
   $topwin.menubar.option add checkbutton -label "Enable infix-wire" -variable infix_wire \
      -selectcolor $selectcolor
+  $topwin.menubar.option add checkbutton -label "Enable orthogonal wiring mode" -variable orthogonal_wiring \
+     -selectcolor $selectcolor  -accelerator Shift+L
   $topwin.menubar.option add checkbutton -label "Unsel. partial sel. wires after stretch move" \
      -selectcolor $selectcolor -variable unselect_partial_sel_wires
 
@@ -8998,6 +9000,7 @@ set_ne persistent_command 0
 set_ne intuitive_interface 1
 set_ne autotrim_wires 0
 set_ne infix_wire 0
+set_ne orthogonal_wiring 1
 set_ne compare_sch 0
 set_ne disable_unique_names 0
 set_ne sym_txt 1

src/xschemrc

@@ -226,6 +226,12 @@
 #### default: 0
 # set infix_wire 1
 
+#### wires are drawn in free-form mode with this mode enabled (default).
+#### if set to 0, wires drawn on the schematic will no longer strictly
+#### follow orthogonal routes to connect two distinct points toegther.
+#### default: 1
+# set orthogonal_wiring 0
+
 #### if set to 1 automatically join/trim wires while editing
 #### this may slow down on rally big designs. Can be disabled via menu 
 #### default: 0