From b0b845193029e5a0329deb7167c30a2ce059b735 Mon Sep 17 00:00:00 2001
From: Sabin Iacob <iacobs@m0n5t3r.info>
Date: Sat, 21 Dec 2019 18:19:17 +0200
Subject: [PATCH] Path: add 2 new arguments to the GRBL postprocessor

---
 src/Mod/Path/PathScripts/post/grbl_post.py | 25 ++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/src/Mod/Path/PathScripts/post/grbl_post.py b/src/Mod/Path/PathScripts/post/grbl_post.py
index be05e684cd..f525f8f9d4 100755
--- a/src/Mod/Path/PathScripts/post/grbl_post.py
+++ b/src/Mod/Path/PathScripts/post/grbl_post.py
@@ -57,6 +57,9 @@ G17 G90
 M2
 '''                               # default postamble text will appear following the last operation.
 
+SPINDLE_WAIT = 0                  # no waiting after M3 / M4 by default
+RETURN_TO = None                  # no movements after end of program
+
 # Customisation with no command line argument
 MODAL = False                     # if true commands are suppressed if the same as previous line.
 LINENR = 100                      # line number starting value
@@ -92,6 +95,8 @@ parser.add_argument('--preamble',                                help='set comma
 parser.add_argument('--postamble',                               help='set commands to be issued after the last command, default="M5\nG17 G90\n;M2"')
 parser.add_argument('--inches',             action='store_true', help='Convert output for US imperial mode (G20)')
 parser.add_argument('--tool-change',        action='store_true', help='Insert M6 for all tool changes')
+parser.add_argument('--wait-for-spindle',   type=int, default=0, help='Wait for spindle to reach desired speed after M3 / M4, default=0')
+parser.add_argument('--return-to',          default='',          help='Move to the specified coordinates at the end, e.g. --return-to=0,0')
 TOOLTIP_ARGS = parser.format_help()
 
 
@@ -128,6 +133,8 @@ def processArguments(argstring):
   global UNIT_FORMAT
   global TRANSLATE_DRILL_CYCLES
   global OUTPUT_TOOL_CHANGE
+  global SPINDLE_WAIT
+  global RETURN_TO
 
   try:
     args = parser.parse_args(shlex.split(argstring))
@@ -163,6 +170,14 @@ def processArguments(argstring):
       PRECISION = 4
     if args.tool_change:
       OUTPUT_TOOL_CHANGE = True
+    if args.wait_for_spindle > 0:
+      SPINDLE_WAIT = args.wait_for_spindle
+    if args.return_to != '':
+      RETURN_TO = [int(v) for v in args.return_to.split(',')]
+      if len(RETURN_TO) != 2:
+        RETURN_TO = None
+        print("--return-to coordinates must be specified as <x>,<y>, ignoring")
+
 
   except Exception as e:
     return False
@@ -248,6 +263,9 @@ def export(objectslist, filename, argstring):
   for line in POSTAMBLE.splitlines(True):
     gcode += linenumber() + line
 
+  if RETURN_TO:
+    gcode += linenumber() + "G0 X%s Y%s" % tuple(RETURN_TO)
+
   # show the gCode result dialog
   if FreeCAD.GuiUp and SHOW_EDITOR:
     dia = PostUtils.GCodeEditorDialog()
@@ -368,6 +386,13 @@ def parse(pathobj):
           del(outstring[:])
           outstring = []
 
+      if SPINDLE_WAIT > 0:
+        if command in ('M3', 'M03', 'M4', 'M04'):
+          out += linenumber() + format_outstring(outstring) + "\n"
+          out += linenumber() + format_outstring(['G4', 'P%s' % SPINDLE_WAIT]) + "\n"
+          del(outstring[:])
+          outstring = []
+
       # Check for Tool Change:
       if command in ('M6', 'M06'):
         if OUTPUT_COMMENTS: