1 #Name: Change Filament At Z
   2 #Info: Pause the print at a certain height, move to a specified parking location, disable extruder stepper
   3 #Help: ChangeFilamentAtZ
   4 #Depend: GCode
   5 #Type: postprocess
   6 #Param: targetZ(float:5.0) Z height to pause at (mm)
   7 #Param: parkX(float:190) Head park X (mm)
   8 #Param: parkY(float:190) Head park Y (mm)
   9 #Param: parkZ(float:150) Head park Z (mm)
  10 #Param: retractAmount(float:5) Retraction amount (mm)
  11 
  12 ## Written by Steven Morlock, smorloc@gmail.com
  13 ## This script is licensed under the Creative Commons - Attribution - Share Alike (CC BY-SA) terms
  14 
  15 import re
  16 
  17 def getValue(line, key, default = None):
  18 	if not key in line or (';' in line and line.find(key) > line.find(';')):
  19 		return default
  20 	subPart = line[line.find(key) + 1:]
  21 	m = re.search('^[0-9]+\.?[0-9]*', subPart)
  22 	if m == None:
  23 		return default
  24 	try:
  25 		return float(m.group(0))
  26 	except:
  27 		return default
  28 
  29 with open(filename, "r") as f:
  30 	lines = f.readlines()
  31 
  32 z = 0
  33 x = 0
  34 y = 0
  35 pauseState = 0
  36 with open(filename, "w") as f:
  37 	for line in lines:
  38 		if getValue(line, 'G', None) == 1 or getValue(line, 'G', None) == 0:
  39 			newZ = getValue(line, 'Z', z)
  40 			x = getValue(line, 'X', x)
  41 			y = getValue(line, 'Y', y)
  42 			if newZ != z:
  43 				z = newZ
  44 				if z < targetZ and pauseState == 0:
  45 					pauseState = 1
  46 				if z >= targetZ and pauseState == 1:
  47 					pauseState = 2
  48 					f.write("; Plugin: start ChangeFilamentAtZ\n")
  49 					# Retract
  50 					f.write("M83\n")		# Set E codes relative while in Absolute Coordinates (G90) 
  51 					f.write("G1 E-%f F6000\n" % (retractAmount))
  52 					# Move the head to specified location
  53 					f.write("G1 X%f Y%f Z%f F9000\n" % (parkX, parkY, parkZ))
  54 					# Disable extruder stepper
  55 					f.write("M84 E\n")					
  56 					# Wait until the user continues printing
  57 					f.write("M0\n")
  58 					# Move the head back to printing location
  59 					f.write("G28 X0 Y0")
  60 					f.write("G1 X0 Y0 F1500")
  61 					f.write("G1 E10 F500")
  62 					f.write("G1 X%f Y%f F9000\n" % (x, y))
  63 					f.write("G1 E0 F6000\n")
  64 					f.write("G1 F9000\n")
  65 					f.write("M82\n")		# Set E codes absolute (default)
  66 					f.write("; Plugin: end ChangeFilamentAtZ\n")					
  67 		f.write(line)