Automatic M104->G10 script Toolchanger / Multi Extruder Printer

[Luke'sLaboratory]

Hey - I did a search and I couldn't find some postprocessing scripts that would automagically insert G10 Rnnn Snnn based on the filaments I had chosen, and after having to remember to change them after a while, I figured I'd have some fun and put together a postprocessing script to automatically convert M104 to G10.

This works for Prusaslicer, Superslic3r, all the forks. I personally use superslicer by supermerill

When you execute the completed gcode, it should turn on the Tool but not pick it up, and then put all tools into standby before beginning the print gcode. The standby temp is chosen by a simple subtraction. For toolchangers where you don't want to use all of the tools or commonly swap filaments, its nice to have something that makes the process a little less manual.

To use it in the slicer, all you need to do is remove M104/M109 commands from your start_gcode, and define your "safe word" that tells the script to put all the tools into standby before going into other actions.

Let me know what issues you find.

#!/usr/bin/python
"""
	Slic3r post-processing script for RepRap firmware printers which prefer G10, particularily useful on toolchangers/IDEX
{1}
Usage:
	Two inputs -
	1)delta_temp - The amount of temperature you want to be subtracted from your active temp. 
		1a) FUTURE WORK - Make this dependent on filament type - more to come
	2)end_phrase - this is what you want to use to end your start gcode so the script can "close up" and deselect the tools.

Slic3r automagically puts M104 before any of your starting gcode, so as long as you have your extruders set up, all of this will be performed before any homing or other motion. 	
Args:
	Path: The path parameter will be provided by Slic3r.
Requirements:
{1}
	The latest version of Python.
	Note that I use this on windows and haven't tried it on any other platform.
{1}
Credit:
{1}
	Based on code originally posted by CCS86 on https://forum.duet3d.com/topic/15302/cura-script-to-automatically-probe-only-printed-area?_=1587348242875. - this is mostly just to import the file automagically, Wasn't sure how to immediately run the file based on slic3r's input.
"""
 
import sys
import re
import math
import os
 
delta_temp = 20   # amount to subtract from the active temp
end_phrase ="Prantin" # String to search for to end your start gcode and insert the T-1 gcode
 
def main(fname, delta_temp, end_phrase):	
	print("BeepBopBoop Scanning...")
	
	try:
		_Slic3rFile = open(fname, encoding='utf-8')
	except TypeError:
		try:
			_Slic3rFile = open(fname)
		except:
			print("Open file exception. Exiting.")
			error()
	except FileNotFoundError:
		print('File not found. Exiting.')
		error()
		
	lines = _Slic3rFile.readlines()
	_Slic3rFile.close()
 
	linesNew = g10_swap(lines,delta_temp, end_phrase)
 
	_Slic3rFile = open(fname, "r+")
	_Slic3rFile.seek(0)                       
	_Slic3rFile.truncate()
	for element in linesNew:
		_Slic3rFile.write(element)
	_Slic3rFile.close()
	print("press any key to close")
	input()
	return
 
def error():
	# remove the next 2 lines to close console automatically
	print("Press Enter to close") 
	input()
	sys.exit()

def g10_swap(lines,delta_temp, end_phrase):

	# Replace M104 with G10 Gcode
    linesNew = []
    tools_used = []
    start_gcode_ended = False
    count=0

    for line in lines:
        if line.startswith('M104'): 
            tool=line[(str.find(line,"T")+1)]
            #tools_used.append(tool) #stores tools
            activetemp=line[(str.find(line,"S")+1):(str.find(line,"S")+4)]
            standbytemp=int(activetemp)-delta_temp
            linesNew.append(f"G10 P{tool} S{activetemp} R{standbytemp}" + "\n") #actual conversion

            if start_gcode_ended==False: #activates tool to get it warmed up - for initial warmups
                linesNew.append(f"T{tool} P0" + "\n")
                count=count+1 #counts quantity of tools, used in removing m109's

            print(f"M104 converted over to G10 T{tool} S{activetemp} R{standbytemp}")
        elif line.startswith("M109") and count>0 and start_gcode_ended==True:
                count = count-1
                continue
        else:
            if end_phrase in line: # Check for end of start gcode
                linesNew.append("T-1 P0" + "\n") #deactivates all tools w/out macros
                start_gcode_ended = True

            linesNew.append(line)
    return linesNew

#main("foo.gcode", delta_temp, end_phrase) #testtesttest

if __name__ == '__main__':
    if sys.argv[1]:
        fname = sys.argv[1]
        main(fname, delta_temp, end_phrase)
    else:
        
        print('Error: Proper Slic3r post processing command is python3')
        error()