src/Mod/CAM/Path/Post/scripts/grbl_legacy_post.py

# ***************************************************************************
# *   Copyright (c) 2014 sliptonic <shopinthewoods@gmail.com>               *
# *   Copyright (c) 2018, 2019 Gauthier Briere                              *
# *   Copyright (c) 2019, 2020 Schildkroet                                  *
# *                                                                         *
# *   This file is part of the FreeCAD CAx development system.              *
# *                                                                         *
# *   This program is free software; you can redistribute it and/or modify  *
# *   it under the terms of the GNU Lesser General Public License (LGPL)    *
# *   as published by the Free Software Foundation; either version 2 of     *
# *   the License, or (at your option) any later version.                   *
# *   for detail see the LICENCE text file.                                 *
# *                                                                         *
# *   FreeCAD 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 Lesser General Public License for more details.                   *
# *                                                                         *
# *   You should have received a copy of the GNU Library General Public     *
# *   License along with FreeCAD; if not, write to the Free Software        *
# *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  *
# *   USA                                                                   *
# *                                                                         *
# ***************************************************************************

import FreeCAD
from FreeCAD import Units
import Path
import Path.Base.Util as PathUtil
import Path.Post.Utils as PostUtils
import PathScripts.PathUtils as PathUtils
import argparse
import datetime
import shlex
import re
from builtins import open as pyopen


TOOLTIP = """
Generate g-code from a Path that is compatible with the grbl controller.
import grbl_legacy_post
grbl_legacy_post.export(object, "/path/to/file.ncc")
"""


# ***************************************************************************
# * Globals set customization preferences
# ***************************************************************************

# Default values for command line arguments:
OUTPUT_COMMENTS = True  # default output of comments in output gCode file
OUTPUT_HEADER = True  # default output header in output gCode file
OUTPUT_LINE_NUMBERS = False  # default doesn't output line numbers in output gCode file
OUTPUT_BCNC = False  # default doesn't add bCNC operation block headers in output gCode file
SHOW_EDITOR = True  # default show the resulting file dialog output in GUI
PRECISION = 3  # Default precision for metric (see http://linuxcnc.org/docs/2.7/html/gcode/overview.html#_g_code_best_practices)
TRANSLATE_DRILL_CYCLES = True  # If true, G81, G82 & G83 are translated in G0/G1 moves
PREAMBLE = """G17 G90
"""  # default preamble text will appear at the beginning of the gCode output file.
POSTAMBLE = """M5
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
LINEINCR = 10  # line number increment
OUTPUT_TOOL_CHANGE = (
    False  # default don't output M6 tool changes (comment it) as grbl currently does not handle it
)
DRILL_RETRACT_MODE = (
    "G98"  # Default value of drill retractations (CURRENT_Z) other possible value is G99
)
MOTION_MODE = "G90"  # G90 for absolute moves, G91 for relative
UNITS = "G21"  # G21 for metric, G20 for us standard
UNIT_FORMAT = "mm"
UNIT_SPEED_FORMAT = "mm/min"
PRE_OPERATION = """"""  # Pre operation text will be inserted before every operation
POST_OPERATION = """"""  # Post operation text will be inserted after every operation
TOOL_CHANGE = """"""  # Tool Change commands will be inserted before a tool change

# ***************************************************************************
# * End of customization
# ***************************************************************************

# Parser arguments list & definition
parser = argparse.ArgumentParser(prog="grbl", add_help=False)
parser.add_argument("--comments", action="store_true", help="output comment (default)")
parser.add_argument("--no-comments", action="store_true", help="suppress comment output")
parser.add_argument("--header", action="store_true", help="output headers (default)")
parser.add_argument("--no-header", action="store_true", help="suppress header output")
parser.add_argument("--line-numbers", action="store_true", help="prefix with line numbers")
parser.add_argument(
    "--no-line-numbers",
    action="store_true",
    help="don't prefix with line numbers (default)",
)
parser.add_argument(
    "--show-editor",
    action="store_true",
    help="pop up editor before writing output (default)",
)
parser.add_argument(
    "--no-show-editor",
    action="store_true",
    help="don't pop up editor before writing output",
)
parser.add_argument("--precision", default="3", help="number of digits of precision, default=3")
parser.add_argument(
    "--translate_drill",
    action="store_true",
    help="translate drill cycles G81, G82 & G83 in G0/G1 movements",
)
parser.add_argument(
    "--no-translate_drill",
    action="store_true",
    help="don't translate drill cycles G81, G82 & G83 in G0/G1 movements (default)",
)
parser.add_argument(
    "--preamble",
    help='set commands to be issued before the first command, default="G17 G90\\n"',
)
parser.add_argument(
    "--postamble",
    help='set commands to be issued after the last command, default="M5\\nG17 G90\\nM2\\n"',
)
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",
)
parser.add_argument(
    "--bcnc",
    action="store_true",
    help="Add Job operations as bCNC block headers. Consider suppressing existing comments: Add argument --no-comments",
)
parser.add_argument(
    "--no-bcnc", action="store_true", help="suppress bCNC block header output (default)"
)
TOOLTIP_ARGS = parser.format_help()


# ***************************************************************************
# * Internal global variables
# ***************************************************************************
MOTION_COMMANDS = [
    "G0",
    "G00",
    "G1",
    "G01",
    "G2",
    "G02",
    "G3",
    "G03",
]  # Motion gCode commands definition
RAPID_MOVES = ["G0", "G00"]  # Rapid moves gCode commands definition
SUPPRESS_COMMANDS = []  # These commands are ignored by commenting them out
COMMAND_SPACE = " "
# Global variables storing current position
CURRENT_X = 0
CURRENT_Y = 0
CURRENT_Z = 0


def processArguments(argstring):

    global OUTPUT_HEADER
    global OUTPUT_COMMENTS
    global OUTPUT_LINE_NUMBERS
    global SHOW_EDITOR
    global PRECISION
    global PREAMBLE
    global POSTAMBLE
    global UNITS
    global UNIT_SPEED_FORMAT
    global UNIT_FORMAT
    global TRANSLATE_DRILL_CYCLES
    global OUTPUT_TOOL_CHANGE
    global SPINDLE_WAIT
    global RETURN_TO
    global OUTPUT_BCNC

    try:
        args = parser.parse_args(shlex.split(argstring))
        if args.no_header:
            OUTPUT_HEADER = False
        if args.header:
            OUTPUT_HEADER = True
        if args.no_comments:
            OUTPUT_COMMENTS = False
        if args.comments:
            OUTPUT_COMMENTS = True
        if args.no_line_numbers:
            OUTPUT_LINE_NUMBERS = False
        if args.line_numbers:
            OUTPUT_LINE_NUMBERS = True
        if args.no_show_editor:
            SHOW_EDITOR = False
        if args.show_editor:
            SHOW_EDITOR = True
        PRECISION = args.precision
        if args.preamble is not None:
            PREAMBLE = args.preamble.replace("\\n", "\n")
        if args.postamble is not None:
            POSTAMBLE = args.postamble.replace("\\n", "\n")
        if args.no_translate_drill:
            TRANSLATE_DRILL_CYCLES = False
        if args.translate_drill:
            TRANSLATE_DRILL_CYCLES = True
        if args.inches:
            UNITS = "G20"
            UNIT_SPEED_FORMAT = "in/min"
            UNIT_FORMAT = "in"
            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")
        if args.bcnc:
            OUTPUT_BCNC = True
        if args.no_bcnc:
            OUTPUT_BCNC = False

    except Exception as e:
        return False

    return True


# For debug...
def dump(obj):
    for attr in dir(obj):
        print("obj.%s = %s" % (attr, getattr(obj, attr)))


def export(objectslist, filename, argstring):

    if not processArguments(argstring):
        return None

    global UNITS
    global UNIT_FORMAT
    global UNIT_SPEED_FORMAT
    global MOTION_MODE
    global SUPPRESS_COMMANDS

    print("Post Processor: " + __name__ + " postprocessing...")
    gcode = ""

    # write header
    if OUTPUT_HEADER:
        gcode += linenumber() + "(Exported by FreeCAD)\n"
        gcode += linenumber() + "(Post Processor: " + __name__ + ")\n"
        gcode += linenumber() + "(Output Time:" + str(datetime.datetime.now()) + ")\n"

    # Check canned cycles for drilling
    if TRANSLATE_DRILL_CYCLES:
        if len(SUPPRESS_COMMANDS) == 0:
            SUPPRESS_COMMANDS = ["G99", "G98", "G80"]
        else:
            SUPPRESS_COMMANDS += ["G99", "G98", "G80"]

    # Write the preamble
    if OUTPUT_COMMENTS:
        gcode += linenumber() + "(Begin preamble)\n"
    for line in PREAMBLE.splitlines():
        gcode += linenumber() + line + "\n"
    # verify if PREAMBLE have changed MOTION_MODE or UNITS
    if "G90" in PREAMBLE:
        MOTION_MODE = "G90"
    elif "G91" in PREAMBLE:
        MOTION_MODE = "G91"
    else:
        gcode += linenumber() + MOTION_MODE + "\n"
    if "G21" in PREAMBLE:
        UNITS = "G21"
        UNIT_FORMAT = "mm"
        UNIT_SPEED_FORMAT = "mm/min"
    elif "G20" in PREAMBLE:
        UNITS = "G20"
        UNIT_FORMAT = "in"
        UNIT_SPEED_FORMAT = "in/min"
    else:
        gcode += linenumber() + UNITS + "\n"

    for obj in objectslist:
        # Debug...
        # print("\n" + "*"*70)
        # dump(obj)
        # print("*"*70 + "\n")
        if not hasattr(obj, "Path"):
            print(
                "The object " + obj.Name + " is not a path. Please select only path and Compounds."
            )
            return

        # Skip inactive operations
        if not PathUtil.activeForOp(obj):
            continue

        # do the pre_op
        if OUTPUT_BCNC:
            gcode += linenumber() + "(Block-name: " + obj.Label + ")\n"
            gcode += linenumber() + "(Block-expand: 0)\n"
            gcode += linenumber() + "(Block-enable: 1)\n"
        if OUTPUT_COMMENTS:
            gcode += linenumber() + "(Begin operation: " + obj.Label + ")\n"
        for line in PRE_OPERATION.splitlines(True):
            gcode += linenumber() + line

        # get coolant mode
        coolantMode = PathUtil.coolantModeForOp(obj)

        # turn coolant on if required
        if OUTPUT_COMMENTS:
            if not coolantMode == "None":
                gcode += linenumber() + "(Coolant On:" + coolantMode + ")\n"
        if coolantMode == "Flood":
            gcode += linenumber() + "M8" + "\n"
        if coolantMode == "Mist":
            gcode += linenumber() + "M7" + "\n"

        # Parse the op
        gcode += parse(obj)

        # do the post_op
        if OUTPUT_COMMENTS:
            gcode += linenumber() + "(Finish operation: " + obj.Label + ")\n"
        for line in POST_OPERATION.splitlines(True):
            gcode += linenumber() + line

        # turn coolant off if required
        if not coolantMode == "None":
            if OUTPUT_COMMENTS:
                gcode += linenumber() + "(Coolant Off:" + coolantMode + ")\n"
            gcode += linenumber() + "M9" + "\n"

    if RETURN_TO:
        gcode += linenumber() + "G0 X%s Y%s\n" % tuple(RETURN_TO)

    # do the post_amble
    if OUTPUT_BCNC:
        gcode += linenumber() + "(Block-name: post_amble)\n"
        gcode += linenumber() + "(Block-expand: 0)\n"
        gcode += linenumber() + "(Block-enable: 1)\n"
    if OUTPUT_COMMENTS:
        gcode += linenumber() + "(Begin postamble)\n"
    for line in POSTAMBLE.splitlines():
        gcode += linenumber() + line + "\n"

    # show the gCode result dialog
    if FreeCAD.GuiUp and SHOW_EDITOR:
        dia = PostUtils.GCodeEditorDialog()
        dia.editor.setPlainText(gcode)
        result = dia.exec_()
        if result:
            final = dia.editor.toPlainText()
        else:
            final = gcode
    else:
        final = gcode

    print("Done postprocessing.")

    # write the file
    if filename != "-":
        with pyopen(filename, "w") as gfile:
            gfile.write(final)

    return final


def linenumber():
    if not OUTPUT_LINE_NUMBERS:
        return ""
    global LINENR
    global LINEINCR
    s = "N" + str(LINENR) + " "
    LINENR += LINEINCR
    return s


def format_outstring(strTable):
    global COMMAND_SPACE
    # construct the line for the final output
    s = ""
    for w in strTable:
        s += w + COMMAND_SPACE
    s = s.strip()
    return s


def parse(pathobj):

    global DRILL_RETRACT_MODE
    global MOTION_MODE
    global CURRENT_X
    global CURRENT_Y
    global CURRENT_Z

    out = ""
    lastcommand = None
    precision_string = "." + str(PRECISION) + "f"

    params = [
        "X",
        "Y",
        "Z",
        "A",
        "B",
        "C",
        "U",
        "V",
        "W",
        "I",
        "J",
        "K",
        "F",
        "S",
        "T",
        "Q",
        "R",
        "L",
        "P",
    ]

    if hasattr(pathobj, "Group"):  # We have a compound or project.
        if OUTPUT_COMMENTS:
            out += linenumber() + "(Compound: " + pathobj.Label + ")\n"
        for p in pathobj.Group:
            out += parse(p)
        return out

    else:  # parsing simple path
        if not hasattr(pathobj, "Path"):  # groups might contain non-path things like stock.
            return out

        if OUTPUT_COMMENTS:
            out += linenumber() + "(Path: " + pathobj.Label + ")\n"

        for c in PathUtils.getPathWithPlacement(pathobj).Commands:
            outstring = []
            command = c.Name

            outstring.append(command)

            # if modal: only print the command if it is not the same as the last one
            if MODAL:
                if command == lastcommand:
                    outstring.pop(0)

            # Now add the remaining parameters in order
            for param in params:
                if param in c.Parameters:
                    if param == "F":
                        if command not in RAPID_MOVES:
                            speed = Units.Quantity(c.Parameters["F"], FreeCAD.Units.Velocity)
                            if speed.getValueAs(UNIT_SPEED_FORMAT) > 0.0:
                                outstring.append(
                                    param
                                    + format(
                                        float(speed.getValueAs(UNIT_SPEED_FORMAT)),
                                        precision_string,
                                    )
                                )
                    elif param in ["T", "H", "S"]:
                        outstring.append(param + str(int(c.Parameters[param])))
                    elif param in ["D", "P", "L"]:
                        outstring.append(param + str(c.Parameters[param]))
                    elif param in ["A", "B", "C"]:
                        outstring.append(param + format(c.Parameters[param], precision_string))
                    else:  # [X, Y, Z, U, V, W, I, J, K, R, Q] (Conversion eventuelle mm/inches)
                        pos = Units.Quantity(c.Parameters[param], FreeCAD.Units.Length)
                        outstring.append(
                            param + format(float(pos.getValueAs(UNIT_FORMAT)), precision_string)
                        )

            # store the latest command
            lastcommand = command

            # Memorizes the current position for calculating the related movements and the withdrawal plan
            if command in MOTION_COMMANDS:
                if "X" in c.Parameters:
                    CURRENT_X = Units.Quantity(c.Parameters["X"], FreeCAD.Units.Length)
                if "Y" in c.Parameters:
                    CURRENT_Y = Units.Quantity(c.Parameters["Y"], FreeCAD.Units.Length)
                if "Z" in c.Parameters:
                    CURRENT_Z = Units.Quantity(c.Parameters["Z"], FreeCAD.Units.Length)

            if command in ("G98", "G99"):
                DRILL_RETRACT_MODE = command

            if command in ("G90", "G91"):
                MOTION_MODE = command

            if TRANSLATE_DRILL_CYCLES:
                if command in ("G81", "G82", "G83"):
                    out += drill_translate(outstring, command, c.Parameters)
                    # Erase the line we just translated
                    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"
                    outstring = []

            # Check for Tool Change:
            if command in ("M6", "M06"):
                if OUTPUT_COMMENTS:
                    out += linenumber() + "(Begin toolchange)\n"
                if not OUTPUT_TOOL_CHANGE:
                    outstring.insert(0, "(")
                    outstring.append(")")
                else:
                    for line in TOOL_CHANGE.splitlines(True):
                        out += linenumber() + line

            if command == "message":
                if OUTPUT_COMMENTS is False:
                    out = []
                else:
                    outstring.pop(0)  # remove the command

            if command in SUPPRESS_COMMANDS:
                outstring.insert(0, "(")
                outstring.append(")")

            # prepend a line number and append a newline
            if len(outstring) >= 1:
                out += linenumber() + format_outstring(outstring) + "\n"

            # Check for comments containing machine-specific commands to pass literally to the controller
            m = re.match(r"^\(MC_RUN_COMMAND: ([^)]+)\)$", command)
            if m:
                raw_command = m.group(1)
                out += linenumber() + raw_command + "\n"

    return out


def drill_translate(outstring, cmd, params):
    global DRILL_RETRACT_MODE
    global MOTION_MODE
    global CURRENT_X
    global CURRENT_Y
    global CURRENT_Z
    global UNITS
    global UNIT_FORMAT
    global UNIT_SPEED_FORMAT

    strFormat = "." + str(PRECISION) + "f"
    trBuff = ""

    if OUTPUT_COMMENTS:  # Comment the original command
        outstring[0] = "(" + outstring[0]
        outstring[-1] = outstring[-1] + ")"
        trBuff += linenumber() + format_outstring(outstring) + "\n"

    # cycle conversion
    # currently only cycles in XY are provided (G17)
    # other plains ZX (G18) and  YZ (G19) are not dealt with : Z drilling only.
    param_X = Units.Quantity(params["X"], FreeCAD.Units.Length)
    param_Y = Units.Quantity(params["Y"], FreeCAD.Units.Length)
    param_Z = Units.Quantity(params["Z"], FreeCAD.Units.Length)
    param_R = Units.Quantity(params["R"], FreeCAD.Units.Length)
    # R less than Z is error
    if param_R < param_Z:
        trBuff += linenumber() + "(drill cycle error: R less than Z )\n"
        return trBuff

    if MOTION_MODE == "G91":  # G91 relative movements, (not generated by CAM WB drilling)
        param_X += CURRENT_X
        param_Y += CURRENT_Y
        param_Z += CURRENT_Z
        param_R += param_Z

    # NIST-RS274
    # 3.5.20 Set Canned Cycle Return Level — G98 and G99
    # When the spindle retracts during canned cycles, there is a choice of how far it retracts: (1) retract
    # perpendicular to the selected plane to the position indicated by the R word, or (2) retract
    # perpendicular to the selected plane to the position that axis was in just before the canned cycle
    # started (unless that position is lower than the position indicated by the R word, in which case use
    # the R word position).
    # To use option (1), program G99. To use option (2), program G98. Remember that the R word has
    # different meanings in absolute distance mode and incremental distance mode.
    # """

    if DRILL_RETRACT_MODE == "G99":
        clear_Z = param_R
    if DRILL_RETRACT_MODE == "G98" and CURRENT_Z >= param_R:
        clear_Z = CURRENT_Z
    else:
        clear_Z = param_R

    strG0_clear_Z = "G0 Z" + format(float(clear_Z.getValueAs(UNIT_FORMAT)), strFormat) + "\n"
    strG0_param_R = "G0 Z" + format(float(param_R.getValueAs(UNIT_FORMAT)), strFormat) + "\n"

    # get the other parameters
    drill_feedrate = Units.Quantity(params["F"], FreeCAD.Units.Velocity)
    strF_Feedrate = " F" + format(float(drill_feedrate.getValueAs(UNIT_SPEED_FORMAT)), ".2f") + "\n"

    if cmd == "G83":
        drill_Step = Units.Quantity(params["Q"], FreeCAD.Units.Length)
        a_bit = (
            drill_Step * 0.05
        )  # NIST 3.5.16.4 G83 Cycle:  "current hole bottom, backed off a bit."
    elif cmd == "G82":
        drill_DwellTime = params["P"]

    # wrap this block to ensure machine MOTION_MODE is restored in case of error
    try:
        if MOTION_MODE == "G91":
            trBuff += linenumber() + "G90\n"  # force absolute coordinates during cycles

        # NIST-RS274
        # 3.5.16.1 Preliminary and In-Between Motion
        # At the very beginning of the execution of any of the canned cycles, with the XY-plane selected, if
        # the current Z position is below the R position, the Z-axis is traversed to the R position. This
        # happens only once, regardless of the value of L.
        # In addition, at the beginning of the first cycle and each repeat, the following one or two moves are
        # made:
        # 1. a straight traverse parallel to the XY-plane to the given XY-position,
        # 2. a straight traverse of the Z-axis only to the R position, if it is not already at the R position.

        if CURRENT_Z < param_R:
            trBuff += linenumber() + strG0_param_R
        trBuff += (
            linenumber()
            + "G0 X"
            + format(float(param_X.getValueAs(UNIT_FORMAT)), strFormat)
            + " Y"
            + format(float(param_Y.getValueAs(UNIT_FORMAT)), strFormat)
            + "\n"
        )
        if CURRENT_Z > param_R:
            trBuff += linenumber() + strG0_param_R

        last_Stop_Z = param_R

        # drill moves
        if cmd in ("G81", "G82"):
            trBuff += (
                linenumber()
                + "G1 Z"
                + format(float(param_Z.getValueAs(UNIT_FORMAT)), strFormat)
                + strF_Feedrate
            )
            # pause where applicable
            if cmd == "G82":
                trBuff += linenumber() + "G4 P" + str(drill_DwellTime) + "\n"
            trBuff += linenumber() + strG0_clear_Z
        else:  # 'G83'
            if params["Q"] != 0:
                while 1:
                    if last_Stop_Z != clear_Z:
                        clearance_depth = (
                            last_Stop_Z + a_bit
                        )  # rapid move to just short of last drilling depth
                        trBuff += (
                            linenumber()
                            + "G0 Z"
                            + format(
                                float(clearance_depth.getValueAs(UNIT_FORMAT)),
                                strFormat,
                            )
                            + "\n"
                        )
                    next_Stop_Z = last_Stop_Z - drill_Step
                    if next_Stop_Z > param_Z:
                        trBuff += (
                            linenumber()
                            + "G1 Z"
                            + format(float(next_Stop_Z.getValueAs(UNIT_FORMAT)), strFormat)
                            + strF_Feedrate
                        )
                        trBuff += linenumber() + strG0_clear_Z
                        last_Stop_Z = next_Stop_Z
                    else:
                        trBuff += (
                            linenumber()
                            + "G1 Z"
                            + format(float(param_Z.getValueAs(UNIT_FORMAT)), strFormat)
                            + strF_Feedrate
                        )
                        trBuff += linenumber() + strG0_clear_Z
                        break

    except Exception as e:
        pass

    if MOTION_MODE == "G91":
        trBuff += linenumber() + "G91"  # Restore if changed

    return trBuff


# print(__name__ + ": GCode postprocessor loaded.")