CNC.py

# -*- coding: ascii -*-
# $Id: CNC.py,v 1.8 2014/10/15 15:03:49 bnv Exp $
#
# Author: vvlachoudis@gmail.com
# Date: 24-Aug-2014

import os
import re
import pdb
import sys
import math
import types
import random
import string

import undo
import Unicode

from dxf   import DXF
from stl   import Binary_STL_Writer
from bpath import eq,Path, Segment
from bmath import *

IDPAT    = re.compile(r".*\bid:\s*(.*?)\)")
PARENPAT = re.compile(r"(\(.*?\))")
SEMIPAT  = re.compile(r"(;.*)")
OPPAT    = re.compile(r"(.*)\[(.*)\]")
CMDPAT   = re.compile(r"([A-Za-z]+)")
BLOCKPAT = re.compile(r"^\(Block-([A-Za-z]+):\s*(.*)\)")
AUXPAT   = re.compile(r"^(%[A-Za-z0-9]+)\b *(.*)$")

STOP   = 0
SKIP   = 1
ASK    = 2
MSG    = 3
WAIT   = 4
UPDATE = 5

XY   = 0
XZ   = 1
YZ   = 2

CW   = 2
CCW  = 3

WCS  = ["G54", "G55", "G56", "G57", "G58", "G59"]

DISTANCE_MODE = { "G90" : "Absolute",
		  "G91" : "Incremental" }
FEED_MODE     = { "G93" : "1/Time",
		  "G94" : "unit/min",
		  "G95" : "unit/rev"}
UNITS         = { "G20" : "inch",
		  "G21" : "mm" }
PLANE         = { "G17" : "XY",
		  "G18" : "ZX",
		  "G19" : "YZ" }

# Modal Mode from $G and variable set
MODAL_MODES = {
	"G0"	: "motion",
	"G1"	: "motion",
	"G2"	: "motion",
	"G3"	: "motion",
	"G38.2"	: "motion",
	"G38.3"	: "motion",
	"G38.4"	: "motion",
	"G38.5"	: "motion",
	"G80"	: "motion",

	"G54"   : "WCS",
	"G55"   : "WCS",
	"G56"   : "WCS",
	"G57"   : "WCS",
	"G58"   : "WCS",
	"G59"   : "WCS",

	"G17"   : "plane",
	"G18"   : "plane",
	"G19"   : "plane",

	"G90"	: "distance",
	"G91"	: "distance",

	"G91.1" : "arc",

	"G93"   : "feedmode",
	"G94"   : "feedmode",
	"G95"   : "feedmode",

	"G20"	: "units",
	"G21"	: "units",

	"G40"	: "cutter",

	"G43.1" : "tlo",
	"G49"   : "tlo",

	"M0"	: "program",
	"M1"	: "program",
	"M2"	: "program",
	"M30"	: "program",

	"M3"    : "spindle",
	"M4"    : "spindle",
	"M5"    : "spindle",

	"M7"    : "coolant",
	"M8"    : "coolant",
	"M9"    : "coolant",
}

ERROR_HANDLING = {}
TOLERANCE = 1e-7
MAXINT    = 1000000000	# python3 doesn't have maxint

#------------------------------------------------------------------------------
# Return a value combined from two dictionaries new/old
#------------------------------------------------------------------------------
def getValue(name,new,old,default=0.0):
	try:
		return new[name]
	except:
		try:
			return old[name]
		except:
			return default

#===============================================================================
# Probing class and linear interpolation
#===============================================================================
class Probe:
	def __init__(self):
		self.init()

	#----------------------------------------------------------------------
	def init(self):
		self.filename = ""
		self.xmin =   0.0
		self.ymin =   0.0
		self.zmin = -10.0

		self.xmax =  10.0
		self.ymax =  10.0
		self.zmax =   3.0

		self._xstep = 1.0
		self._ystep = 1.0

		self.xn = 5
		self.yn = 5

		self.points = []	# probe points
		self.matrix = []	# 2D matrix with Z coordinates
		self.zeroed = False	# if probe was zeroed at any location
		self.start  = False	# start collecting probes
		self.saved  = False

	#----------------------------------------------------------------------
	def clear(self):
		del self.points[:]
		del self.matrix[:]
		self.zeroed = False
		self.start  = False
		self.saved  = False

	#----------------------------------------------------------------------
	def isEmpty(self): return len(self.matrix)==0

	#----------------------------------------------------------------------
	def makeMatrix(self):
		del self.matrix[:]
		for j in range(self.yn):
			self.matrix.append([0.0]*(self.xn))

	#----------------------------------------------------------------------
	# Load autolevel information from file
	#----------------------------------------------------------------------
	def load(self, filename=None):
		if filename is not None:
			self.filename = filename
		self.clear()
		self.saved = True

		def read(f):
			while True:
				line = f.readline()
				if len(line)==0: raise
				line = line.strip()
				if line: return map(float, line.split())

		f = open(self.filename,"r")
		self.xmin, self.xmax, self.xn = read(f)
		self.ymin, self.ymax, self.yn = read(f)
		self.zmin, self.zmax, feed    = read(f)
		CNC.vars["prbfeed"] = feed

		self.xn = max(2,int(self.xn))
		self.yn = max(2,int(self.yn))

		self.makeMatrix()
		self.xstep()
		self.ystep()

		self.start = True
		try:
			for j in range(self.yn):
				for i in range(self.xn):
					self.add(*read(f))
		except:
			raise
			#print "Error reading probe file",self.filename
		f.close()

	#----------------------------------------------------------------------
	# Save level information to file
	#----------------------------------------------------------------------
	def save(self, filename=None):
		if filename is not None:
			self.filename = filename
		f = open(self.filename,"w")
		f.write("%g %g %d\n"%(self.xmin, self.xmax, self.xn))
		f.write("%g %g %d\n"%(self.ymin, self.ymax, self.yn))
		f.write("%g %g %g\n"%(self.zmin, self.zmax, CNC.vars["prbfeed"]))
		f.write("\n\n")
		for j in range(self.yn):
			y = self.ymin + self._ystep*j
			for i in range(self.xn):
				x = self.xmin + self._xstep*i
				f.write("%g %g %g\n"%(x,y,self.matrix[j][i]))
			f.write("\n")
		f.close()
		self.saved = True

	#----------------------------------------------------------------------
	# Save level information as STL file
	#----------------------------------------------------------------------
	def saveAsSTL(self, filename=None):
		if filename is not None:
			self.filename = filename

		with open(self.filename, 'wb') as fp:
			writer = Binary_STL_Writer(fp)
			for j in range(self.yn -1):
				y1 = self.ymin + self._ystep*j
				y2 = self.ymin + self._ystep*(j+1)
				for i in range(self.xn -1):
					x1 = self.xmin + self._xstep*i
					x2 = self.xmin + self._xstep*(i+1)
					v1=[x1,y1,self.matrix[j][i]]
					v2=[x2,y1,self.matrix[j][i+1]]
					v3=[x2,y2,self.matrix[j+1][i+1]]
					v4=[x1,y2,self.matrix[j+1][i]]
					writer.add_face([v1,v2,v3,v4])
			writer.close()

	#----------------------------------------------------------------------
	# Return step
	#----------------------------------------------------------------------
	def xstep(self):
		self._xstep = (self.xmax-self.xmin)/float(self.xn-1)
		return self._xstep

	#----------------------------------------------------------------------
	def ystep(self):
		self._ystep = (self.ymax-self.ymin)/float(self.yn-1)
		return self._ystep

	#----------------------------------------------------------------------
	# Return the code needed to scan for autoleveling
	#----------------------------------------------------------------------
	def scan(self):
		self.clear()
		self.start = True
		self.makeMatrix()
		x = self.xmin
		xstep = self._xstep
		lines = ["G0Z%.4f"%(CNC.vars["safe"]),
			 "G0X%.4fY%.4f"%(self.xmin, self.ymin)]
		for j in range(self.yn):
			y = self.ymin + self._ystep*j
			for i in range(self.xn):
				lines.append("G0Z%.4f"%(self.zmax))
				lines.append("G0X%.4fY%.4f"%(x,y))
				lines.append("%wait")	# added for smoothie
				lines.append("%sZ%.4fF%g"%(CNC.vars["prbcmd"], self.zmin, CNC.vars["prbfeed"]))
				lines.append("%wait")	# added for smoothie
				x += xstep
			x -= xstep
			xstep = -xstep
		lines.append("G0Z%.4f"%(self.zmax))
		lines.append("G0X%.4fY%.4f"%(self.xmin,self.ymin))
		return lines

	#----------------------------------------------------------------------
	# Add a probed point to the list and the 3D matrix
	#----------------------------------------------------------------------
	def add(self, x,y,z):
		if not self.start: return
		i = round((x-self.xmin) / self._xstep)
		if i<0.0 or i>self.xn: return

		j = round((y-self.ymin) / self._ystep)
		if j<0.0 or j>self.yn: return

		rem = abs(x - (i*self._xstep + self.xmin))
		if rem > self._xstep/10.0: return

		rem = abs(y - (j*self._ystep + self.ymin))
		if rem > self._ystep/10.0: return

		try:
			self.matrix[int(j)][int(i)] = z
			self.points.append([x,y,z])
		except IndexError:
			pass

		if len(self.points) >= self.xn*self.yn:
			self.start = False

	#----------------------------------------------------------------------
	# Make z-level relative to the location of (x,y,0)
	#----------------------------------------------------------------------
	def setZero(self, x, y):
		del self.points[:]
		if self.isEmpty():
			self.zeroed = False
			return
		zero = self.interpolate(x,y)
		self.xstep()
		self.ystep()
		for j,row in enumerate(self.matrix):
			y = self.ymin + self._ystep*j
			for i in range(len(row)):
				x = self.xmin + self._xstep*i
				row[i] -= zero
				self.points.append([x,y,row[i]])
		self.zeroed = True

	#----------------------------------------------------------------------
	def interpolate(self, x, y):
		ix = (x-self.xmin) / self._xstep
		jy = (y-self.ymin) / self._ystep
		i = int(math.floor(ix))
		j = int(math.floor(jy))

		if i<0:
			i = 0
		elif i>=self.xn-1:
			i = self.xn-2

		if j<0:
			j = 0
		elif j>=self.yn-1:
			j = self.yn-2

		a = ix - i
		b = jy - j
		a1 = 1.0 - a
		b1 = 1.0 - b

		return a1*b1 * self.matrix[j][i]   + \
		       a1*b  * self.matrix[j+1][i] + \
		       a *b1 * self.matrix[j][i+1] + \
		       a *b  * self.matrix[j+1][i+1]

	#----------------------------------------------------------------------
	# Split line into multiple segments correcting for Z if needed
	# return only end points
	#----------------------------------------------------------------------
	def splitLine(self, x1, y1, z1, x2, y2, z2):
		dx = x2-x1
		dy = y2-y1
		dz = z2-z1

		if abs(dx)<1e-10: dx = 0.0
		if abs(dy)<1e-10: dy = 0.0
		if abs(dz)<1e-10: dz = 0.0

		if dx==0.0 and dy==0.0:
			return [(x2,y2,z2+self.interpolate(x2,y2))]

		# Length along projection on X-Y plane
		rxy = math.sqrt(dx*dx + dy*dy)
		dx /= rxy	# direction cosines along XY plane
		dy /= rxy
		dz /= rxy	# add correction for the slope in Z, versus the travel in XY

		i = int(math.floor((x1-self.xmin) / self._xstep))
		j = int(math.floor((y1-self.ymin) / self._ystep))
		if dx > 1e-10:
			tx  = (float(i+1)*self._xstep+self.xmin - x1)/ dx	# distance to next cell
			tdx = self._xstep / dx
		elif dx < -1e-10:
			tx  = (float(i)*self._xstep+self.xmin - x1)/ dx		# distance to next cell
			tdx = -self._xstep / dx
		else:
			tx  = 1e10
			tdx = 0.0

		if dy > 1e-10:
			ty  = (float(j+1)*self._ystep+self.ymin - y1)/ dy	# distance to next cell
			tdy = self._ystep / dy
		elif dy < -1e-10:
			ty  = (float(j)*self._ystep+self.ymin - y1)/ dy		# distance to next cell
			tdy = -self._ystep / dy
		else:
			ty  = 1e10
			tdy = 0.0

		segments = []
		rxy *= 0.999999999	# just reduce a bit to avoid precision errors
		while tx<rxy or ty<rxy:
			if tx==ty:
				t = tx
				tx += tdx
				ty += tdy
			elif tx<ty:
				t = tx
				tx += tdx
			else:
				t = ty
				ty += tdy
			x = x1 + t*dx
			y = y1 + t*dy
			z = z1 + t*dz
			segments.append((x,y,z+self.interpolate(x,y)))

		segments.append((x2,y2,z2+self.interpolate(x2,y2)))
		return segments

#===============================================================================
# contains a list of machine points vs position in the gcode
# calculates the transformation matrix (rotation + translation) needed
# to adjust the gcode to match the workpiece on the machine
#===============================================================================
class Orient:
	#-----------------------------------------------------------------------
	def __init__(self):
		self.markers = []		# list of points pairs (xm, ym, x, y)
						# xm,ym = machine x,y mpos
						# x, y  = desired or gcode location
		self.paths   = []
		self.errors  = []
		self.filename = ""
		self.clear()

	#-----------------------------------------------------------------------
	def clear(self, item=None):
		if item is None:
			self.clearPaths()
			del self.markers[:]
		else:
			del self.paths[item]
			del self.markers[item]

		self.phi = 0.0
		self.xo  = 0.0
		self.yo  = 0.0
		self.valid = False
		self.saved = False

	#-----------------------------------------------------------------------
	def clearPaths(self):
		del self.paths[:]

	#-----------------------------------------------------------------------
	def add(self, xm, ym, x, y):
		self.markers.append((xm,ym,x,y))
		self.valid = False
		self.saved = False

	#-----------------------------------------------------------------------
	def addPath(self, path):
		self.paths.append(path)

	#-----------------------------------------------------------------------
	def __getitem__(self, i):
		return self.markers[i]

	#-----------------------------------------------------------------------
	def __len__(self):
		return len(self.markers)

	#-----------------------------------------------------------------------
	# Return the rotation angle phi in radians and the offset (xo,yo)
	# or none on failure
	# Transformation equation is the following
	#
	#    Xm = R * X + T
	#
	#    Xm = [xm ym]^t
	#    X  = [x y]^t
	#
	#
	#       / cosf  -sinf \   / c  -s \
	#   R = |             | = |       |
	#       \ sinf   cosf /   \ s   c /
	#
	# Assuming that the machine is squared. We could even solve it for
	# a skewed machine, but then the arcs have to be converted to
	# ellipses...
	#
	#   T = [xo yo]^t
	#
	# The overdetermined system (equations) to solve are the following
	#      c*x + s*(-y) + xo      = xm
	#      s*x + c*y    + yo      = ym
	#  <=> c*y + s*y         + yo = ym
	#
	# We are solving for the unknowns c,s,xo,yo
	#
	#       /  x1  -y1  1 0 \ / c  \    / xm1 \
	#       |  y1   x1  0 1 | | s  |    | ym1 |
	#       |  x2  -y2  1 0 | | xo |    | xm2 |
	#       |  y2   x2  0 1 | \ yo /  = | ym2 |
	#	      ...                   ..
	#       |  xn  -yn  1 0 |           | xmn |
	#       \  yn   xn  0 1 /           \ ymn /
	#
	#               A            X    =    B
	#
	# Constraints:
	#   1. orthogonal system   c^2 + s^2 = 1
	#   2. no aspect ratio
	#
	#-----------------------------------------------------------------------
	def solve(self):
		self.valid = False
		if len(self.markers)< 2: raise Exception("Too few markers")
		A = []
		B = []
		for xm,ym,x,y in self.markers:
			A.append([x,-y,1.0,0.0]);	B.append([xm])
			A.append([y, x,0.0,1.0]);	B.append([ym])

		# The solution of the overdetermined system A X = B
		try:
			c,s,self.xo,self.yo = solveOverDetermined(Matrix(A),Matrix(B))
		except:
			raise Exception("Unable to solve system")

		#print "c,s,xo,yo=",c,s,xo,yo

		# Normalize the coefficients
		r = sqrt(c*c + s*s)	# length should be 1.0
		if abs(r-1.0) > 0.1:
			raise Exception("Resulting system is too skew")

#		print "r=",r
		#xo /= r
		#yo /= r
		self.phi = atan2(s, c)

		if abs(self.phi)<TOLERANCE: self.phi = 0.0	# rotation

		self.valid = True
		return self.phi,self.xo,self.yo

	#-----------------------------------------------------------------------
	# @return minimum, average and maximum error
	#-----------------------------------------------------------------------
	def error(self):
		# Type errors
		minerr = 1e9
		maxerr = 0.0
		sumerr = 0.0

		c = cos(self.phi)
		s = sin(self.phi)

		del self.errors[:]

		for i,(xm,ym,x,y) in enumerate(self.markers):
			dx = c*x - s*y + self.xo - xm
			dy = s*x + c*y + self.yo - ym
			err = sqrt(dx**2 + dy**2)
			self.errors.append(err)

			minerr = min(minerr, err)
			maxerr = max(maxerr, err)
			sumerr += err

		return minerr, sumerr/float(len(self.markers)), maxerr

	#-----------------------------------------------------------------------
	# Convert gcode to machine coordinates
	#-----------------------------------------------------------------------
	def gcode2machine(self, x, y):
		c = cos(self.phi)
		s = sin(self.phi)
		return	c*x - s*y + self.xo, \
			s*x + c*y + self.yo

	#-----------------------------------------------------------------------
	# Convert machine to gcode coordinates
	#-----------------------------------------------------------------------
	def machine2gcode(self, x, y):
		c = cos(self.phi)
		s = sin(self.phi)
		x -= self.xo
		y -= self.yo
		return	 c*x + s*y, \
			-s*x + c*y

	#----------------------------------------------------------------------
	# Load orient information from file
	#----------------------------------------------------------------------
	def load(self, filename=None):
		if filename is not None:
			self.filename = filename
		self.clear()
		self.saved = True

		f = open(self.filename,"r")
		for line in f:
			self.add(*map(float, line.split()))
		f.close()

	#----------------------------------------------------------------------
	# Save orient information to file
	#----------------------------------------------------------------------
	def save(self, filename=None):
		if filename is not None:
			self.filename = filename
		f = open(self.filename,"w")
		for xm,ym,x,y in self.markers:
			f.write("%g %g %g %g\n"%(xm,ym,x,y))
		f.close()
		self.saved = True

#===============================================================================
# Command operations on a CNC
#===============================================================================
class CNC:
	inch           = False
	lasercutter    = False
	acceleration_x = 25.0	# mm/s^2
	acceleration_y = 25.0	# mm/s^2
	acceleration_z = 25.0	# mm/s^2
	acceleration_a = 25.0	# mm/s^2
	feedmax_x      = 3000
	feedmax_y      = 3000
	feedmax_z      = 2000
	feedmax_a      = 2000
	travel_x       = 300
	travel_y       = 300
	travel_z       = 60
	travel_a       = 300
	accuracy       = 0.02	# sagitta error during arc conversion
	digits         = 4
	startup        = "G90"
	stdexpr        = False	# standard way of defining expressions with []
	comment        = ""	# last parsed comment
	developer      = False
	drozeropad     = 0
	vars           = {
			"prbx"       : 0.0,
			"prby"       : 0.0,
			"prbz"       : 0.0,
			"prba"       : 0.0,
			"prbcmd"     : "G38.2",
			"prbfeed"    : 10.,
			"errline"    : "",
			"wx"         : 0.0,
			"wy"         : 0.0,
			"wz"         : 0.0,
			"wa"         : 0.0,
			"mx"         : 0.0,
			"my"         : 0.0,
			"mz"         : 0.0,
			"ma"         : 0.0,
			"wcox"       : 0.0,
			"wcoy"       : 0.0,
			"wcoz"       : 0.0,
			"wcoa"       : 0.0,
			"curfeed"    : 0.0,
			"curspindle" : 0.0,
			"_camwx"     : 0.0,
			"_camwy"     : 0.0,
			"G"          : [],
			"TLO"        : 0.0,
			"motion"     : "G0",
			"WCS"        : "G54",
			"plane"      : "G17",
			"feedmode"   : "G94",
			"distance"   : "G90",
			"arc"        : "G91.1",
			"units"      : "G20",
			"cutter"     : "",
			"tlo"        : "",
			"program"    : "M0",
			"spindle"    : "M5",
			"coolant"    : "M9",

			"tool"       : 0,
			"feed"       : 0.0,
			"rpm"        : 0.0,

			"planner"    : 0,
			"rxbytes"    : 0,

			"OvFeed"     : 100,	# Override status
			"OvRapid"    : 100,
			"OvSpindle"  : 100,
			"_OvChanged" : False,
			"_OvFeed"    : 100,	# Override target values
			"_OvRapid"   : 100,
			"_OvSpindle" : 100,

			"diameter"   : 3.175,	# Tool diameter
			"cutfeed"    : 1000.,	# Material feed for cutting
			"cutfeedz"   : 500.,	# Material feed for cutting
			"safe"       : 3.,
			"state"      : "",
			"msg"        : "",
			"stepz"      : 1.,
			"surface"    : 0.,
			"thickness"  : 5.,
			"stepover"   : 40.,

			"PRB"        : None,
			"TLO"        : 0.,

			"version"    : "",
			"running"    : False,
		}

	drillPolicy    = 1		# Expand Canned cycles
	toolPolicy     = 1		# Should be in sync with ProbePage
					# 0 - send to grbl
					# 1 - skip those lines
					# 2 - manual tool change (WCS)
					# 3 - manual tool change (TLO)
					# 4 - manual tool change (No Probe)

	toolWaitAfterProbe = True	# wait at tool change position after probing
	appendFeed	   = False	# append feed on every G1/G2/G3 commands to be used
					# for feed override testing
					# FIXME will not be needed after Grbl v1.0

	#----------------------------------------------------------------------
	def __init__(self):
		self.initPath()
		self.resetAllMargins()

	#----------------------------------------------------------------------
	# Update G variables from "G" string
	#----------------------------------------------------------------------
	@staticmethod
	def updateG():
		for g in CNC.vars["G"]:
			if g[0] == "F":
				CNC.vars["feed"] = float(g[1:])
			elif g[0] == "S":
				CNC.vars["rpm"] = float(g[1:])
			elif g[0] == "T":
				CNC.vars["tool"] = int(g[1:])
			else:
				var = MODAL_MODES.get(g)
				if var is not None:
					CNC.vars[var] = g

	#----------------------------------------------------------------------
	def __getitem__(self, name):
		return CNC.vars[name]

	#----------------------------------------------------------------------
	def __setitem__(self, name, value):
		CNC.vars[name] = value

	#----------------------------------------------------------------------
	@staticmethod
	def loadConfig(config):
		section = "CNC"
		try: CNC.inch           = bool(int(config.get(section, "units")))
		except: pass
		try: CNC.lasercutter    = bool(int(config.get(section, "lasercutter")))
		except: pass
		try: CNC.doublesizeicon = bool(int(config.get(section, "doublesizeicon")))
		except: pass
		try: CNC.acceleration_x = float(config.get(section, "acceleration_x"))
		except: pass
		try: CNC.acceleration_y = float(config.get(section, "acceleration_y"))
		except: pass
		try: CNC.acceleration_z = float(config.get(section, "acceleration_z"))
		except: pass
		try: CNC.acceleration_a = float(config.get(section, "acceleration_a"))
		except: pass
		try: CNC.feedmax_x      = float(config.get(section, "feedmax_x"))
		except: pass
		try: CNC.feedmax_y      = float(config.get(section, "feedmax_y"))
		except: pass
		try: CNC.feedmax_z      = float(config.get(section, "feedmax_z"))
		except: pass
		try: CNC.feedmax_a      = float(config.get(section, "feedmax_a"))
		except: pass
		try: CNC.travel_x       = float(config.get(section, "travel_x"))
		except: pass
		try: CNC.travel_y       = float(config.get(section, "travel_y"))
		except: pass
		try: CNC.travel_z       = float(config.get(section, "travel_z"))
		except: pass
		try: CNC.travel_a       = float(config.get(section, "travel_a"))
		except: pass
		try: CNC.accuracy       = float(config.get(section, "accuracy"))
		except: pass
		try: CNC.digits         = int(  config.get(section, "round"))
		except: pass
		try: CNC.drozeropad     = int(  config.get(section, "drozeropad"))
		except: pass

		CNC.startup = config.get(section, "startup")
		CNC.header  = config.get(section, "header")
		CNC.footer  = config.get(section, "footer")

		if CNC.inch:
			CNC.acceleration_x  /= 25.4
			CNC.acceleration_y  /= 25.4
			CNC.acceleration_z  /= 25.4
			CNC.acceleration_a  /= 25.4
			CNC.feedmax_x       /= 25.4
			CNC.feedmax_y       /= 25.4
			CNC.feedmax_z       /= 25.4
			CNC.feedmax_a       /= 25.4
			CNC.travel_x        /= 25.4
			CNC.travel_y        /= 25.4
			CNC.travel_z        /= 25.4
			CNC.travel_a        /= 25.4

		section = "Error"
		for cmd,value in config.items(section):
			try:
				ERROR_HANDLING[cmd.upper()] = int(value)
			except:
				pass

	#----------------------------------------------------------------------
	@staticmethod
	def saveConfig(config):
		pass

	#----------------------------------------------------------------------
	def initPath(self, x=None, y=None, z=None, a=None):
		if x is None:
			self.x = self.xval = 0
		else:
			self.x = self.xval = x
		if y is None:
			self.y = self.yval = 0
		else:
			self.y = self.yval = y
		if z is None:
			self.z = self.zval = 0
		else:
			self.z = self.zval = z
		if a is None:
			self.a = self.aval = 0
		else:
			self.a = self.aval = a
		self.ival = self.jval = self.kval = 0.0
		self.uval = self.vval = self.wval = 0.0
		self.dx   = self.dy   = self.dz   = self.da = 0.0
		self.di   = self.dj   = self.dk   = 0.0
		self.rval = 0.0
		self.pval = 0.0
		self.qval = 0.0
		self.unit = 1.0
		self.mval = 0
		self.lval = 1
		self.tool = 0
		self._lastTool = None

		self.absolute    = True		# G90/G91     absolute/relative motion
		self.arcabsolute = False	# G90.1/G91.1 absolute/relative arc
		self.retractz    = True		# G98/G99     retract to Z or R
		self.gcode       = None
		self.plane       = XY
		self.feed        = 0		# Actual gcode feed rate (not to confuse with cutfeed
		self.totalLength = 0.0
		self.totalTime   = 0.0

	#----------------------------------------------------------------------
	def resetEnableMargins(self):
		# Selected blocks margin
		CNC.vars["xmin"]  = CNC.vars["ymin"]  = CNC.vars["zmin"]  =  1000000.0
		CNC.vars["xmax"]  = CNC.vars["ymax"]  = CNC.vars["zmax"]  = -1000000.0

	#----------------------------------------------------------------------
	def resetAllMargins(self):
		self.resetEnableMargins()
		# All blocks margin
		CNC.vars["axmin"] = CNC.vars["aymin"] = CNC.vars["azmin"] =  1000000.0
		CNC.vars["axmax"] = CNC.vars["aymax"] = CNC.vars["azmax"] = -1000000.0

	#----------------------------------------------------------------------
	@staticmethod
	def isMarginValid():
		return	CNC.vars["xmin"] <= CNC.vars["xmax"] and \
			CNC.vars["ymin"] <= CNC.vars["ymax"] and \
			CNC.vars["zmin"] <= CNC.vars["zmax"]

	#----------------------------------------------------------------------
	@staticmethod
	def isAllMarginValid():
		return	CNC.vars["axmin"] <= CNC.vars["axmax"] and \
			CNC.vars["aymin"] <= CNC.vars["aymax"] and \
			CNC.vars["azmin"] <= CNC.vars["azmax"]

	#----------------------------------------------------------------------
	# Number formating
	#----------------------------------------------------------------------
	@staticmethod
	def fmt(c, v, d=None):
		if d is None: d = CNC.digits
		return ("%s%*f"%(c,d,v)).rstrip("0").rstrip(".")

	#----------------------------------------------------------------------
	@staticmethod
	def gcode(g, pairs):
		s = "g%d"%(g)
		for c,v in pairs:
			s += " %c%g"%(c, round(v,CNC.digits))
		return s

	#----------------------------------------------------------------------
	@staticmethod
	def _gcode(g, **args):
		s = "g%d"%(g)
		for n,v in args.items():
			s += ' ' + CNC.fmt(n,v)
		return s

	#----------------------------------------------------------------------
	@staticmethod
	def _goto(g, x=None, y=None, z=None, **args):
		s = "g%d"%(g)
		if x is not None: s += ' '+CNC.fmt('x',x)
		if y is not None: s += ' '+CNC.fmt('y',y)
		if z is not None: s += ' '+CNC.fmt('z',z)
		for n,v in args.items():
			s += ' ' + CNC.fmt(n,v)
		return s

	#----------------------------------------------------------------------
	@staticmethod
	def grapid(x=None, y=None, z=None, **args):
		return CNC._goto(0,x,y,z,**args)

	#----------------------------------------------------------------------
	@staticmethod
	def gline(x=None, y=None, z=None, **args):
		return CNC._goto(1,x,y,z,**args)

	#----------------------------------------------------------------------
	@staticmethod
	def glinev(g, v, feed=None):
		pairs = zip("xyz",v)
		if feed is not None:
			pairs.append(("f",feed))
		return CNC.gcode(g, pairs)

	#----------------------------------------------------------------------
	@staticmethod
	def garcv(g, v, ijk):
		return CNC.gcode(g, zip("xyz",v) + zip("ij",ijk[:2]))

	#----------------------------------------------------------------------
	@staticmethod
	def garc(g, x=None, y=None, z=None, i=None, j=None, k=None, **args):
		s = "g%d"%(g)
		if x is not None: s += ' '+CNC.fmt('x',x)
		if y is not None: s += ' '+CNC.fmt('y',y)
		if z is not None: s += ' '+CNC.fmt('z',z)
		if i is not None: s += ' '+CNC.fmt('i',i)
		if j is not None: s += ' '+CNC.fmt('j',j)
		if k is not None: s += ' '+CNC.fmt('k',k)
		for n,v in args.items():
			s += ' ' + CNC.fmt(n,v)
		return s

	#----------------------------------------------------------------------
	# Enter to material or start the laser
	#----------------------------------------------------------------------
	@staticmethod
	def zenter(z):
		if CNC.lasercutter:
			return "m3"
		else:
			return "g1 %s %s"%(CNC.fmt("z",z), CNC.fmt("f",CNC.vars["cutfeedz"]))

	#----------------------------------------------------------------------
	@staticmethod
	def zexit(z):
		if CNC.lasercutter:
			return "m5"
		else:
			return "g0 %s"%(CNC.fmt("z",z))

	#----------------------------------------------------------------------
	# gcode to go to z-safe
	# Exit from material or stop the laser
	#----------------------------------------------------------------------
	@staticmethod
	def zsafe():
		return CNC.zexit(CNC.vars["safe"])

	#----------------------------------------------------------------------
	# @return line in broken a list of commands, None if empty or comment
	#----------------------------------------------------------------------
	@staticmethod
	def parseLine(line):
		# skip empty lines
		if len(line)==0 or line[0] in ("%","(","#",";"):
			return None

		# remove comments
		line = PARENPAT.sub("",line)
		line = SEMIPAT.sub("",line)

		# process command
		# strip all spaces
		line = line.replace(" ","")

		# Insert space before each command
		line = CMDPAT.sub(r" \1",line).lstrip()
		return line.split()

	# -----------------------------------------------------------------------------
	# @return line,comment
	#	line broken in a list of commands,
	#       None,"" if empty or comment
	#       else compiled expressions,""
	#----------------------------------------------------------------------
	@staticmethod
	def compileLine(line, space=False):
		line = line.strip()
		if not line: return None
		if line[0] == "$": return line

		# to accept #nnn variables as _nnn internally
		line = line.replace('#','_')
		CNC.comment = ""

		# execute literally the line after the first character
		if line[0]=='%':
			# special command
			pat = AUXPAT.match(line.strip())
			if pat:
				cmd  = pat.group(1)
				args = pat.group(2)
			else:
				cmd  = None
				args = None
			if cmd=="%wait":
				return (WAIT,)
			elif cmd=="%msg":
				if not args: args = None
				return (MSG, args)
			elif cmd=="%update":
				return (UPDATE, args)
			elif line.startswith("%if running") and not CNC.vars["running"]:
				# ignore if running lines when not running
				return None
			else:
				try:
					return compile(line[1:],"","exec")
				except:
					# FIXME show the error!!!!
					return None

		# most probably an assignment like  #nnn = expr
		if line[0]=='_':
			try:
				return compile(line,"","exec")
			except:
				# FIXME show the error!!!!
				return None

		# commented line
		if line[0] == ';':
			CNC.comment = line[1:].strip()
			return None

		out    = []		# output list of commands
		braket = 0		# bracket count []
		paren  = 0		# parenthesis count ()
		expr   = ""		# expression string
		cmd    = ""		# cmd string
		inComment = False	# inside inComment
		for i,ch in enumerate(line):
			if ch == '(':
				# comment start?
				paren += 1
				inComment = (braket==0)
				if not inComment:
					expr += ch
			elif ch == ')':
				# comment end?
				paren -= 1
				if not inComment: expr += ch
				if paren==0 and inComment: inComment=False
			elif ch == '[':
				# expression start?
				if not inComment:
					if CNC.stdexpr: ch='('
					braket += 1
					if braket==1:
						if cmd:
							out.append(cmd)
							cmd = ""
					else:
						expr += ch
				else:
					CNC.comment += ch
			elif ch == ']':
				# expression end?
				if not inComment:
					if CNC.stdexpr: ch=')'
					braket -= 1
					if braket==0:
						try:
							out.append(compile(expr,"","eval"))
						except:
							# FIXME show the error!!!!
							pass
						#out.append("<<"+expr+">>")
						expr = ""
					else:
						expr += ch
				else:
					CNC.comment += ch
			elif ch=='=':
				# check for assignments (FIXME very bad)
				if not out and braket==0 and paren==0:
					for i in " ()-+*/^$":
						if i in cmd:
							cmd += ch
							break
					else:
						try:
							return compile(line,"","exec")
						except:
							# FIXME show the error!!!!
							return None
			elif ch == ';':
				# Skip everything after the semicolon on normal lines
				if not inComment and paren==0 and braket==0:
					CNC.comment += line[i+1:]
					break
				else:
					expr += ch

			elif braket>0:
				expr += ch

			elif not inComment:
				if ch == ' ':
					if space:
						cmd += ch
				else:
					cmd += ch

			elif inComment:
				CNC.comment += ch

		if cmd: out.append(cmd)

		# return output commands
		if len(out)==0:
			return None
		if len(out)>1:
			return out
		return out[0]

	#----------------------------------------------------------------------
	# Break line into commands
	#----------------------------------------------------------------------
	@staticmethod
	def breakLine(line):
		if line is None: return None
		# Insert space before each command
		line = CMDPAT.sub(r" \1",line).lstrip()
		return line.split()

	#----------------------------------------------------------------------
	# Create path for one g command
	#----------------------------------------------------------------------
	def motionStart(self, cmds):
		#print "\n<<<",cmds
		self.mval = 0	# reset m command
		for cmd in cmds:
			c = cmd[0].upper()
			try:
				value = float(cmd[1:])
			except:
				value = 0

			if   c == "X":
				self.xval = value*self.unit
				if not self.absolute:
					self.xval += self.x
				self.dx = self.xval - self.x

			elif c == "Y":
				self.yval = value*self.unit
				if not self.absolute:
					self.yval += self.y
				self.dy = self.yval - self.y

			elif c == "Z":
				self.zval = value*self.unit
				if not self.absolute:
					self.zval += self.z
				self.dz = self.zval - self.z

			elif c == "A":
				self.aval = value*self.unit

			elif c == "F":
				self.feed = value*self.unit

			elif c == "G":
				gcode = int(value)
				decimal = int(round((value - gcode)*10))

				# Execute immediately
				if gcode in (4,10,53):
					pass	# do nothing but don't record to motion
				elif gcode==17:
					self.plane = XY

				elif gcode==18:
					self.plane = XZ

				elif gcode==19:
					self.plane = YZ

				elif gcode==20:	# Switch to inches
					if CNC.inch:
						self.unit = 1.0
					else:
						self.unit = 25.4

				elif gcode==21:	# Switch to mm
					if CNC.inch:
						self.unit = 1.0/25.4
					else:
						self.unit = 1.0

				elif gcode==80:
					# turn off canned cycles
					self.gcode = None
					self.dz    = 0
					self.zval  = self.z

				elif gcode==90:
					if decimal == 0:
						self.absolute = True
					elif decimal == 1:
						self.arcabsolute = True

				elif gcode==91:
					if decimal == 0:
						self.absolute = False
					elif decimal == 1:
						self.arcabsolute = False

				elif gcode in (93,94,95):
					CNC.vars["feedmode"] = gcode

				elif gcode==98:
					self.retractz = True

				elif gcode==99:
					self.retractz = False

				else:
					self.gcode = gcode

			elif c == "I":
				self.ival = value*self.unit
				if self.arcabsolute:
					self.ival -= self.x

			elif c == "J":
				self.jval = value*self.unit
				if self.arcabsolute:
					self.jval -= self.y

			elif c == "K":
				self.kval = value*self.unit
				if self.arcabsolute:
					self.kval -= self.z

			elif c == "L":
				self.lval = int(value)

			elif c == "M":
				self.mval = int(value)

			elif c == "N":
				pass

			elif c == "P":
				self.pval = value

			elif c == "Q":
				self.qval = value*self.unit

			elif c == "R":
				self.rval = value*self.unit

			elif c == "T":
				self.tool = int(value)

			elif c == "U":
				self.uval = value*self.unit

			elif c == "V":
				self.vval = value*self.unit

			elif c == "W":
				self.wval = value*self.unit

	#----------------------------------------------------------------------
	# Return center x,y,z,r for arc motions 2,3 and set self.rval
	#----------------------------------------------------------------------
	def motionCenter(self):
		if self.rval>0.0:
			if self.plane == XY:
				x  = self.x
				y  = self.y
				xv = self.xval
				yv = self.yval
			elif self.plane == XZ:
				x  = self.x
				y  = self.z
				xv = self.xval
				yv = self.zval
			else:
				x  = self.y
				y  = self.z
				xv = self.yval
				yv = self.zval

			ABx = xv-x
			ABy = yv-y
			Cx  = 0.5*(x+xv)
			Cy  = 0.5*(y+yv)
			AB  = math.sqrt(ABx**2 + ABy**2)
			try: OC  = math.sqrt(self.rval**2 - AB**2/4.0)
			except: OC = 0.0
			if self.gcode==2: OC = -OC	# CW
			if AB != 0.0:
				return Cx-OC*ABy/AB, Cy + OC*ABx/AB
			else:
				# Error!!!
				return x,y
		else:
			# Center
			xc = self.x + self.ival
			yc = self.y + self.jval
			zc = self.z + self.kval
			self.rval = math.sqrt(self.ival**2 + self.jval**2 + self.kval**2)

			if self.plane == XY:
				return xc,yc
			elif self.plane == XZ:
				return xc,zc
			else:
				return yc,zc

		# Error checking
		#err = abs(self.rval - math.sqrt((self.xval-xc)**2 + (self.yval-yc)**2 + (self.zval-zc)**2))
		#if err/self.rval>0.001:
			#print "Error invalid arc", self.xval, self.yval, self.zval, err
		#return xc,yc,zc

	#----------------------------------------------------------------------
	# Create path for one g command
	#----------------------------------------------------------------------
	def motionPath(self):
		xyza = []

		# Execute g-code
		if self.gcode in (0,1):	# fast move or line
			if self.xval-self.x != 0.0 or \
			   self.yval-self.y != 0.0 or \
			   self.zval-self.z != 0.0 or \
			   self.aval-self.a != 0.0:
				xyza.append((self.x,self.y,self.z,self.a))
				xyza.append((self.xval,self.yval,self.zval,self.aval))

		elif self.gcode in (2,3):	# CW=2,CCW=3 circle
			xyza.append((self.x,self.y,self.z,self.a))
			uc,vc = self.motionCenter()

			gcode = self.gcode
			if self.plane == XY:
				u0 = self.x
				v0 = self.y
				w0 = self.z
				u1 = self.xval
				v1 = self.yval
				w1 = self.zval
			elif self.plane == XZ:
				u0 = self.x
				v0 = self.z
				w0 = self.y
				u1 = self.xval
				v1 = self.zval
				w1 = self.yval
				gcode = 5-gcode	# flip 2-3 when XZ plane is used
			elif self.plane == XAF:
				u0 = self.x
				v0 = self.a
				w0 = self.z
				u1 = self.xval
				v1 = self.aval
				w1 = self.zval
				#gcode = 5-gcode	# flip 2-3 when XZ plane is used
			else:
				u0 = self.y
				v0 = self.z
				w0 = self.x
				u1 = self.yval
				v1 = self.zval
				w1 = self.xval
			phi0 = math.atan2(v0-vc, u0-uc)
			phi1 = math.atan2(v1-vc, u1-uc)
			try:
				sagitta = 1.0-CNC.accuracy/self.rval
			except ZeroDivisionError:
				sagitta = 0.0
			if sagitta>0.0:
				df = 2.0*math.acos(sagitta)
				df = min(df, math.pi/4.0)
			else:
				df = math.pi/4.0

			if gcode==2:
				if phi1>=phi0-1e-10: phi1 -= 2.0*math.pi
				ws  = (w1-w0)/(phi1-phi0)
				phi = phi0 - df
				while phi>phi1:
					u = uc + self.rval*math.cos(phi)
					v = vc + self.rval*math.sin(phi)
					w = w0 + (phi-phi0)*ws
					phi -= df
					if self.plane == XY:
						xyza.append((u,v,w))
					elif self.plane == XAF:
						xyza.append((u,v,w))
					elif self.plane == XZ:
						xyza.append((u,w,v))
					else:
						xyza.append((w,u,v))
			else:
				if phi1<=phi0+1e-10: phi1 += 2.0*math.pi
				ws  = (w1-w0)/(phi1-phi0)
				phi = phi0 + df
				while phi<phi1:
					u = uc + self.rval*math.cos(phi)
					v = vc + self.rval*math.sin(phi)
					w = w0 + (phi-phi0)*ws
					phi += df
					if self.plane == XY:
						xyza.append((u,v,w))
					elif self.plane == XAF:
						xyza.append((u,v,w))
					elif self.plane == XZ:
						xyza.append((u,w,v))
					else:
						xyza.append((w,u,v))

			xyza.append((self.xval,self.yval,self.zval,self.aval))

		elif self.gcode==4:		# Dwell
			self.totalTime = self.pval

		elif self.gcode in (81,82,83,85,86,89): # Canned cycles
			#print "x=",self.x
			#print "y=",self.y
			#print "z=",self.z
			#print "dx=",self.dx
			#print "dy=",self.dy
			#print "dz=",self.dz
			#print "abs=",self.absolute,"retract=",self.retractz

			# FIXME Assuming only on plane XY
			if self.absolute:
				# FIXME is it correct?
				self.lval = 1
				if self.retractz:
					clearz = max(self.rval, self.z)
				else:
					clearz = self.rval
				drill  = self.zval
			else:
				clearz = self.z + self.rval
				drill  = clearz + self.dz
			#print "clearz=",clearz
			#print "drill=",drill

			x,y,z,a = self.x, self.y, self.z, self.a
			xyza.append((x,y,z,a))
			if z != clearz:
				z = clearz
				xyza.append((x,y,z,a))
			for l in range(self.lval):
				# Rapid move parallel to XY
				x += self.dx
				y += self.dy
				xyza.append((x,y,z,a))

				# Rapid move parallel to clearz
				if self.z > clearz:
					xyza.append((x,y,clearz,a))

				# Drill to z
				xyza.append((x,y,drill,a))

				# Move to original position
				z = clearz
				xyza.append((x,y,z,a))	# ???

		#for a in xyza: print a

		return xyza

	#----------------------------------------------------------------------
	# move to end position
	#----------------------------------------------------------------------
	def motionEnd(self):
		#print "x=",self.x
		#print "y=",self.y
		#print "z=",self.z
		#print "dx=",self.dx
		#print "dy=",self.dy
		#print "dz=",self.dz
		#print "abs=",self.absolute,"retract=",self.retractz

		if self.gcode in (0,1,2,3):
			self.x = self.xval
			self.y = self.yval
			self.z = self.zval
			self.a = self.aval
			self.dx = 0
			self.dy = 0
			self.dz = 0
			self.da = 0

			if self.gcode >= 2: # reset at the end
				self.rval = self.ival = self.jval = self.kval = 0.0

		elif self.gcode in (28,30,92):
			self.x = 0.0
			self.y = 0.0
			self.z = 0.0
			self.a = 0.0
			self.dx = 0
			self.dy = 0
			self.dz = 0
			self.da = 0

		# FIXME L is not taken into account for repetitions!!!
		elif self.gcode in (81,82,83):
			# FIXME Assuming only on plane XY
			if self.absolute:
				self.lval = 1
				if self.retractz:
					retract = max(self.rval, self.z)
				else:
					retract = self.rval
				drill = self.zval
			else:
				retract = self.z + self.rval
				drill   = retract + self.dz

			self.x += self.dx*self.lval
			self.y += self.dy*self.lval
			self.z  = retract
			self.a += self.da*self.lval

			self.xval = self.x
			self.yval = self.y
			self.aval = self.a
			self.dx = 0
			self.dy = 0
			self.dz = drill - retract
			self.da = 0

	#----------------------------------------------------------------------
	# Doesn't work correctly for G83 (peck drilling)
	#----------------------------------------------------------------------
	def pathLength(self, block, xyza):
		# For XY plan
		p = xyza[0]
		length = 0.0
		for i in xyza:
			length += math.sqrt((i[0]-p[0])**2 + (i[1]-p[1])**2 + (i[2]-p[2])**2)
			p = i

		if self.gcode == 0:
			# FIXME calculate the correct time with the feed direction
			# and acceleration
			block.time += length / self.feedmax_x
			self.totalTime += length / self.feedmax_x
			block.rapid += length
		else:
			try:
				if CNC.vars["feedmode"] == 94:
					# Normal mode
					t = length / self.feed
				elif CNC.vars["feedmode"] == 93:
					# Inverse mode
					t = length * self.feed

				block.time += t
				self.totalTime += t
			except:
				pass
			block.length += length

		self.totalLength += length

	#----------------------------------------------------------------------
	def pathMargins(self, block):
		if block.enable:
			CNC.vars["xmin"] = min(CNC.vars["xmin"], block.xmin)
			CNC.vars["ymin"] = min(CNC.vars["ymin"], block.ymin)
			CNC.vars["zmin"] = min(CNC.vars["zmin"], block.zmin)
			CNC.vars["xmax"] = max(CNC.vars["xmax"], block.xmax)
			CNC.vars["ymax"] = max(CNC.vars["ymax"], block.ymax)
			CNC.vars["zmax"] = max(CNC.vars["zmax"], block.zmax)

		CNC.vars["axmin"] = min(CNC.vars["axmin"], block.xmin)
		CNC.vars["aymin"] = min(CNC.vars["aymin"], block.ymin)
		CNC.vars["azmin"] = min(CNC.vars["azmin"], block.zmin)
		CNC.vars["axmax"] = max(CNC.vars["axmax"], block.xmax)
		CNC.vars["aymax"] = max(CNC.vars["aymax"], block.ymax)
		CNC.vars["azmax"] = max(CNC.vars["azmax"], block.zmax)

	#----------------------------------------------------------------------
	# Instead of the current code, override with the custom user lines
	# @param program a list of lines to execute
	# @return the new list of lines
	#----------------------------------------------------------------------
	@staticmethod
	def compile(program):
		lines = []
		for j,line in enumerate(program):
			newcmd = []
			cmds = CNC.compileLine(line)
			if cmds is None: continue
			if isinstance(cmds,str) or isinstance(cmds,unicode):
				cmds = CNC.breakLine(cmds)
			else:
				# either CodeType or tuple, list[] append at it as is
				lines.append(cmds)
				continue

			for cmd in cmds:
				c = cmd[0]
				try: value = float(cmd[1:])
				except: value = 0.0
				if c.upper() in ("F","X","Y","Z","I","J","K","R","P"):
					cmd = CNC.fmt(c,value)
				else:
					opt = ERROR_HANDLING.get(cmd.upper(),0)
					if opt == SKIP: cmd = None

				if cmd is not None:
					newcmd.append(cmd)
			lines.append("".join(newcmd))
		return lines

	#----------------------------------------------------------------------
	# code to change manually tool
	#----------------------------------------------------------------------
	def toolChange(self, tool=None):
		if tool is not None:
			# Force a change
			self.tool = tool
			self._lastTool = None

		# check if it is the same tool
		if self.tool is None or self.tool == self._lastTool: return []

		# create the necessary code
		lines = []
		lines.append("$g")	# remember state and populate variables
		lines.append("m5")	# stop spindle
		lines.append("%wait")
		lines.append("%_x,_y,_z,_a = wx,wy,wz,wa")	# remember position
		lines.append("g53 g0 z[toolchangez]")
		lines.append("g53 g0 x[toolchangex] y[toolchangey]")
		lines.append("%wait")

		if CNC.comment:
			lines.append("%%msg Tool change T%02d (%s)"%(self.tool,CNC.comment))
		else:
			lines.append("%%msg Tool change T%02d"%(self.tool))
		lines.append("m0")	# feed hold

		if CNC.toolPolicy < 4:
			lines.append("g53 g0 x[toolprobex] y[toolprobey]")
			lines.append("g53 g0 z[toolprobez]")

			# fixed WCS
			if CNC.vars["fastprbfeed"]:
				prb_reverse = {"2": "4", "3": "5", "4": "2", "5": "3"}
				CNC.vars["prbcmdreverse"] = (CNC.vars["prbcmd"][:-1] +
							     prb_reverse[CNC.vars["prbcmd"][-1]])
				currentFeedrate = CNC.vars["fastprbfeed"]
				while currentFeedrate > CNC.vars["prbfeed"]:
					lines.append("g91 [prbcmd] f%f z[-tooldistance]" % currentFeedrate)
					lines.append("g91 [prbcmdreverse] f%f z[tooldistance]" % currentFeedrate)
					currentFeedrate /= 10
			lines.append("g91 [prbcmd] f[prbfeed] z[-tooldistance]")

			if CNC.toolPolicy==2:
				# Adjust the current WCS to fit to the tool
				# FIXME could be done dynamically in the code
				p = WCS.index(CNC.vars["WCS"])+1
				lines.append("G10L20P%d z[toolheight]"%(p))
				lines.append("%wait")

			elif CNC.toolPolicy==3:
				# Modify the tool length, update the TLO
				lines.append("g4 p1")	# wait a sec to get the probe info
				lines.append("%wait")
				lines.append("%global TLO; TLO=prbz-toolmz")
				lines.append("g43.1z[TLO]")
				lines.append("%update TLO")

			lines.append("g53 g0 z[toolchangez]")
			lines.append("g53 g0 x[toolchangex] y[toolchangey]")

		if CNC.toolWaitAfterProbe:
			lines.append("%wait")
			lines.append("%msg Restart spindle")
			lines.append("m0")	# feed hold

		# restore state
		lines.append("g90")		# restore mode
		lines.append("g0 x[_x] y[_y]")	# ... x,y position
		lines.append("g0 z[_z]")	# ... z position
		lines.append("f[feed] [spindle]")# ... feed and spindle

		# remember present tool
		self._lastTool = self.tool
		return lines

	#----------------------------------------------------------------------
	# code to expand G80-G89 macro code - canned cycles
	# example:
	# code to expand G83 code - peck drilling cycle
	# format:	(G98 / G99 opt.) G83 X~ Y~ Z~ A~ R~ L~ Q~
	# example:	N150 G98 G83 Z-1.202 R18. Q10. F50.
	#			...
	#			G80
	# Notes: G98, G99, Z, R, Q, F are unordered parameters
	#----------------------------------------------------------------------
	def macroGroupG8X(self):
		lines = []

		#print "x=",self.x
		#print "y=",self.y
		#print "z=",self.z
		#print "dx=",self.dx
		#print "dy=",self.dy
		#print "dz=",self.dz
		#print "abs=",self.absolute,"retract=",self.retractz

		# FIXME Assuming only on plane XY
		if self.absolute:
			# FIXME is it correct?
			self.lval = 1
			if self.retractz:
				clearz = max(self.rval, self.z)
			else:
				clearz = self.rval
			drill   = self.zval
			retract = self.rval
		else:
			clearz  = self.z + self.rval
			retract = clearz
			drill   = clearz + self.dz
		#print "clearz=",clearz
		#print "drill=",drill

		if self.gcode == 83:	# peck drilling
			peck = self.qval
		else:
			peck = 100000.0	# a large value

		x,y,z = self.x, self.y, self.z
		if z < clearz:
			z = clearz
			lines.append(CNC.grapid(z=z/self.unit))

		for l in range(self.lval):
			# Rapid move parallel to XY
			x += self.dx
			y += self.dy
			lines.append(CNC.grapid(x/self.unit,y/self.unit))

			# Rapid move parallel to retract
			zstep = max(drill, retract - peck)
			while z > drill:
				if z != retract:
					z = retract
					lines.append(CNC.grapid(z=z/self.unit))

				z = max(drill, zstep)
				zstep -= peck

				# Drill to z
				lines.append(CNC.gline(z=z/self.unit,f=self.feed))

			# 82=dwell, 86=boring-stop, 89=boring-dwell
			if self.gcode in (82,86,89):
				lines.append(CNC._gcode(4,p=self.pval))

				if self.gcode == 86:
					lines.append("M5")	# stop spindle???

			# Move to original position
			if self.gcode in (85,89):	# boring cycle
				z = retract
				lines.append(CNC.gline(z=z/self.unit,f=self.feed))

			z = clearz
			lines.append(CNC.grapid(z=z/self.unit))

			if self.gcode == 86:
				lines.append("M3")	# restart spindle???
		#print "-"*50
		#for a in lines: print a
		#print "-"*50
		return lines

#===============================================================================
# a class holding tab information and necessary functions to break a segment
#===============================================================================
class Tab:
	def __init__(self, x, y, dx, dy, z):
		self.x  = x			# x,y limits of a square tab
		self.y  = y
		self.dx = dx
		self.dy = dy
		self.z  = z			# z to raise within the tab
		self.path = None

	#----------------------------------------------------------------------
	def copy(self, src):
		self.x  = src.x			# x,y limits of a square tab
		self.y  = src.y
		self.dx = src.dx
		self.dy = src.dy
		self.z  = src.z			# z to raise within the tab

	#----------------------------------------------------------------------
	def __str__(self):
		return "Tab([%g, %g] x [%g, %g] z=%g)" % \
			(self.x, self.y, self.dx, self.dy, self.z)

	#----------------------------------------------------------------------
	# parse and return parameters of the __str__(function above)
	#----------------------------------------------------------------------
	@staticmethod
	def parse(s):
		# replace all non digits to space, split and convert to float
		return map(float, re.sub("[^0-9.]"," ",s).split())

	#----------------------------------------------------------------------
	# Tab string entry in listbox
	#----------------------------------------------------------------------
#	def entry(self):
#		return "Tab: %g %g %g %g %g"

	#----------------------------------------------------------------------
	# Correct tab for min/max
	#----------------------------------------------------------------------
#	def correct(self):
#		if self.xmin > self.xmax:
#			self.xmin, self.xmax = self.xmax, self.xmin
#		if self.ymin > self.ymax:
#			self.ymin, self.ymax = self.ymax, self.ymin

	#----------------------------------------------------------------------
	def save(self):
		return self.x, self.y, self.dx, self.dy, self.z

	#----------------------------------------------------------------------
	def restore(self, params):
		self.x  = params[0]
		self.y  = params[1]
		self.dx = params[2]
		self.dy = params[3]
		self.z  = params[4]

	#----------------------------------------------------------------------
	def move(self, dx, dy, dz=None):
		self.x += dx
		self.y += dy

	#----------------------------------------------------------------------
	def transform(self, c, s, xo, yo):
		xn = c*self.x - s*self.y + xo
		yn = s*self.x + c*self.y + yo
		self.x = xn
		self.y = yn

	#----------------------------------------------------------------------
	# Create 4 line segment of the tab
	#----------------------------------------------------------------------
	def create(self, diameter=0.0):
		r = diameter/2.0
		self.segments = []

		dx = self.dx/2. + r
		dy = self.dy/2. + r

		A = A0 = Vector(self.x-dx, self.y-dy)
		B = Vector(self.x+dx, self.y-dy)
		self.segments.append(Segment(Segment.LINE, A, B))
		A = B
		B = Vector(self.x+dx, self.y+dy)
		self.segments.append(Segment(Segment.LINE, A, B))
		A = B
		B = Vector(self.x-dx, self.y+dy)
		self.segments.append(Segment(Segment.LINE, A, B))
		A = B
		B = A0
		self.segments.append(Segment(Segment.LINE, A, B))

	#----------------------------------------------------------------------
	# return true if a point is inside the tab or not
	#----------------------------------------------------------------------
	def inside(self, P):
		return self.x-self.dx/2. <= P[0] <= self.x+self.dx/2. and \
		       self.y-self.dy/2. <= P[1] <= self.y+self.dy/2.

	#----------------------------------------------------------------------
	# Split and introduce new segments that fall inside the tabs
	# All segments will be marked with an extra field "inside"
	# whether they are in or out
	#----------------------------------------------------------------------
	def split(self, path):
		for A in self.segments:
			i = 0	# starting point
			while i<len(path):
				split = False
				B = path[i]
				P1,P2 = A.intersect(B)
				if P1 is not None:
					C = B.split(P1)
					if not isinstance(C,int):
						path.insert(i+1,C)
						split = True

				if P2 is not None and (P1 is None or not eq(P1,P2)):
					if B.inside(P2):
						j = i
					else:
						j = i+1

					C = path[j].split(P2)
					if not isinstance(C,int):
						path.insert(j+1,C)
						split = True

				if split: continue # restart from same location
				i += 1

		for s in path:
			if s._inside is None and self.inside(s.midPoint()):
				s._inside = self

#===============================================================================
# Block of g-code commands. A gcode file is represented as a list of blocks
# - Commands are grouped as (non motion commands Mxxx)
# - Basic shape from the first rapid move command to the last rapid z raise
#   above the working surface
#
# Inherits from list and contains:
#	- a list list of gcode lines
#	- (imported shape)
#===============================================================================
class Block(list):
	def __init__(self, name=None):
		# Copy constructor
		if isinstance(name, Block):
			self.copy(name)
			return
		self._name    = name
		self.enable   = True		# Enabled/Visible in drawing
		self.expand   = False		# Expand in editor
		self.color    = None		# Custom color for path
		self.tabs     = []		# Tabs on block
		self._path    = []		# canvas drawing paths
		self.sx = self.sy = self.sz = self.sa = 0	# start  coordinates
						# (entry point first non rapid motion)
		self.ex = self.ey = self.ez = self.ea = 0	# ending coordinates
		self.resetPath()

	#----------------------------------------------------------------------
	def copy(self, src):
		self._name  = src._name
		self.enable = src.enable
		self.expand = src.expand
		self.color  = src.color
		self.tabs   = []
		for tab in src.tabs:
			self.tabs.append(Tab(tab.x, tab.y, tab.dx, tab.dy, tab.z))
		self[:]     = src[:]
		self._path  = []
		self.sx = src.sx
		self.sy = src.sy
		self.sz = src.sz
		self.sa = src.sa
		self.ex = src.ex
		self.ey = src.ey
		self.ez = src.ez
		self.ea = src.ea

	#----------------------------------------------------------------------
	def name(self):
		return self._name is None and "block" or self._name

	#----------------------------------------------------------------------
	# @return name without the operation
	#----------------------------------------------------------------------
	def nameNop(self):
		name = self.name()
		pat = OPPAT.match(name)
		if pat is None:
			return name
		else:
			return pat.group(1).strip()

	#----------------------------------------------------------------------
	# @return the new name with an operation (static)
	#----------------------------------------------------------------------
	@staticmethod
	def operationName(name, operation, remove=None):
		pat = OPPAT.match(name)
		if pat is None:
			return "%s [%s]"%(name,operation)
		else:
			name = pat.group(1).strip()
			ops = pat.group(2).split(',')
			if ":" in operation:
				oid,opt = operation.split(":")
			else:
				oid = operation
				opt = None

			found = False
			for i,o in enumerate(ops):
				if ":" in o:
					o,c = o.split(":")
					try:
						c = int(c)
					except:
						c = 1
				else:
					c = 1

				if remove and o in remove: ops[i]=""
				if not found and o==oid:
					if opt is not None or c is None:
						ops[i] = operation
					else:
						ops[i] = "%s:%d"%(oid,c+1)
					found = True

			# remove all empty
			ops = filter(lambda x:x!="", ops)

			if not found:
				ops.append(operation)

			return "%s [%s]"%(name,','.join(ops))

	#----------------------------------------------------------------------
	# Add a new operation to the block's name
	#----------------------------------------------------------------------
	def addOperation(self, operation, remove=None):
		n = self.name()
		self._name = Block.operationName(self.name(), operation, remove)

	#----------------------------------------------------------------------
	def header(self):
		e = self.expand and Unicode.BLACK_DOWN_POINTING_TRIANGLE \
				or  Unicode.BLACK_RIGHT_POINTING_TRIANGLE
		v = self.enable and Unicode.BALLOT_BOX_WITH_X \
				or  Unicode.BALLOT_BOX
		try:
			return "%s %s %s - [%d]"%(e, v, self.name(), len(self))
		except UnicodeDecodeError:
			return "%s %s %s - [%d]"%(e, v, self.name().decode("ascii","replace"), len(self))

	#----------------------------------------------------------------------
	def write(self, f):
		f.write("(Block-name: %s)\n"%(self.name()))
		f.write("(Block-expand: %d)\n"%(int(self.expand)))
		f.write("(Block-enable: %d)\n"%(int(self.enable)))
		if self.color:
			f.write("(Block-color: %s)\n"%(self.color))
		for tab in self.tabs:
			f.write("(Block-tab: %g %g %g %g %g)\n"% \
				(tab.x, tab.y, tab.dx, tab.dy, tab.z))
		f.write("%s\n"%("\n".join(self)))

	#----------------------------------------------------------------------
	# Return a dump object for pickler
	#----------------------------------------------------------------------
	def dump(self):
		return self.name(), self.enable, self.expand, self.color, self

	#----------------------------------------------------------------------
	# Create a block from a dump object from unpickler
	#----------------------------------------------------------------------
	@staticmethod
	def load(obj):
		name, enable, expand, color, code = obj
		block = Block(name)
		block.enable = enable
		block.expand = expand
		block.color = color
		block.extend(code)
		return block

	#----------------------------------------------------------------------
	def append(self, line):
		if line.startswith("(Block-"):
			pat = BLOCKPAT.match(line)
			if pat:
				name, value = pat.groups()
				value = value.strip()
				if name=="name":
					self._name = value
					return
				elif name=="expand":
					self.expand = bool(int(value))
					return
				elif name=="enable":
					self.enable = bool(int(value))
					return
				elif name=="tab":
					items = map(float,value.split())
					self.tabs.append(Tab(*items))
					return
				elif name=="color":
					self.color = value
					return
		if self._name is None and ("id:" in line) and ("End" not in line):
			pat = IDPAT.match(line)
			if pat: self._name = pat.group(1)
		list.append(self, line)

	#----------------------------------------------------------------------
	def resetPath(self):
		del self._path[:]
		self.xmin = self.ymin = self.zmin = self.amin = 1000000.0
		self.xmax = self.ymax = self.zmax = self.amax =-1000000.0
		self.length = 0.0	# cut length
		self.rapid  = 0.0	# rapid length
		self.time   = 0.0

	#----------------------------------------------------------------------
	def hasPath(self):
		return bool(self._path)

	#----------------------------------------------------------------------
	def addPath(self, p):
		self._path.append(p)

	#----------------------------------------------------------------------
	def path(self, item):
		try:
			return self._path[item]
		except:
			return None

	#----------------------------------------------------------------------
	def startPath(self, x, y, z, a):
		self.sx = x
		self.sy = y
		self.sz = z
		self.sa = a

	#----------------------------------------------------------------------
	def endPath(self, x, y, z, a):
		self.ex = x
		self.ey = y
		self.ez = z
		self.ea = a

	#----------------------------------------------------------------------
	def pathMargins(self, xyza):
		self.xmin = min(self.xmin, min([i[0] for i in xyza]))
		self.ymin = min(self.ymin, min([i[1] for i in xyza]))
		self.zmin = min(self.zmin, min([i[2] for i in xyza]))
		self.xmax = max(self.xmax, max([i[0] for i in xyza]))
		self.ymax = max(self.ymax, max([i[1] for i in xyza]))
		self.zmax = max(self.zmax, max([i[2] for i in xyza]))
		self.amin = min(self.amin, min([0.] + [i[3] for i in xyza if len(i) > 3]))
		self.amax = max(self.amax, max([0.] + [i[3] for i in xyza if len(i) > 3]))

#===============================================================================
# Gcode file
#===============================================================================
class GCode:
	LOOP_MERGE = False

	#----------------------------------------------------------------------
	def __init__(self):
		self.cnc = CNC()
		self.header   = ""
		self.footer   = ""
		self.undoredo = undo.UndoRedo()
		self.probe    = Probe()
		self.orient   = Orient()
		self.vars     = {}		# local variables
		self.init()

	#----------------------------------------------------------------------
	def init(self):
		self.filename = ""
		self.blocks   = []		# list of blocks
#		self.tabs     = []		# list of tabs
		self.vars.clear()
		self.undoredo.reset()
#		self.probe.init()

		self._lastModified = 0
		self._modified = False

	#----------------------------------------------------------------------
	# Recalculate enabled path margins
	#----------------------------------------------------------------------
	def calculateEnableMargins(self):
		self.cnc.resetEnableMargins()
		for block in self.blocks:
			if block.enable:
				CNC.vars["xmin"] = min(CNC.vars["xmin"], block.xmin)
				CNC.vars["ymin"] = min(CNC.vars["ymin"], block.ymin)
				CNC.vars["zmin"] = min(CNC.vars["zmin"], block.zmin)
				CNC.vars["xmax"] = max(CNC.vars["xmax"], block.xmax)
				CNC.vars["ymax"] = max(CNC.vars["ymax"], block.ymax)
				CNC.vars["zmax"] = max(CNC.vars["zmax"], block.zmax)

	#----------------------------------------------------------------------
	def isModified(self): return self._modified

	#----------------------------------------------------------------------
	def resetModified(self): self._modified = False

	#----------------------------------------------------------------------
	def __getitem__(self, item):		return self.blocks[item]
	def __setitem__(self, item, value):	self.blocks[item] = value

	#----------------------------------------------------------------------
	# Evaluate code expressions if any and return line
	#----------------------------------------------------------------------
	def evaluate(self, line):
		if isinstance(line,int):
			return None

		elif isinstance(line,list):
			for i,expr in enumerate(line):
				if isinstance(expr, types.CodeType):
					result = eval(expr,CNC.vars,self.vars)
					if isinstance(result,float):
						line[i] = str(round(result,CNC.digits))
					else:
						line[i] = str(result)
			return "".join(line)

		elif isinstance(line, types.CodeType):
			return eval(line,CNC.vars,self.vars)

		else:
			return line

	#----------------------------------------------------------------------
	# add new line to list create block if necessary
	#----------------------------------------------------------------------
	def _addLine(self, line):
#		if line.startswith("(Tab:"):
#			items = map(float,line.replace("(Tab:","").replace(")","").split())
#			self.tabs.append(Tab(*items))
#			return

		if line.startswith("(Block-name:"):
			self._blocksExist = True
			pat = BLOCKPAT.match(line)
			if pat:
				value = pat.group(2).strip()
				if not self.blocks or len(self.blocks[-1]):
					self.blocks.append(Block(value))
				else:
					self.blocks[-1]._name = value
				return

		if not self.blocks:
			self.blocks.append(Block("Header"))

		cmds = CNC.parseLine(line)
		if cmds is None:
			self.blocks[-1].append(line)
			return

		self.cnc.motionStart(cmds)

		# rapid move up = end of block
		if self._blocksExist:
			self.blocks[-1].append(line)
		elif self.cnc.gcode == 0 and self.cnc.dz > 0.0:
			self.blocks[-1].append(line)
			self.blocks.append(Block())
		elif self.cnc.gcode == 0 and len(self.blocks)==1:
			self.blocks.append(Block())
			self.blocks[-1].append(line)
		else:
			self.blocks[-1].append(line)

		self.cnc.motionEnd()

	#----------------------------------------------------------------------
	# Load a file into editor
	#----------------------------------------------------------------------
	def load(self, filename=None):
		if filename is None: filename = self.filename
		self.init()
		self.filename = filename
		try: f = open(self.filename,"r")
		except: return False
		self._lastModified = os.stat(self.filename).st_mtime
		self.cnc.initPath()
		self.cnc.resetAllMargins()
		self._blocksExist = False
		for line in f:
			self._addLine(line[:-1].replace("\x0d",""))
		self._trim()
		f.close()
		return True

	#----------------------------------------------------------------------
	# Save to a file
	#----------------------------------------------------------------------
	def save(self, filename=None):
		if filename is not None: self.filename = filename
		try:
			f = open(self.filename,"w")
		except:
			return False

		# write tabs if any
#		for tab in self.tabs:
#			f.write("(Tab:%g %g %g %g %g)\n"%(tab.xmin, tab.ymin, tab.xmax, tab.ymax, tab.z))
		for block in self.blocks:
			block.write(f)
		f.close()
		self._lastModified = os.stat(self.filename).st_mtime
		self._modified = False
		return True

	#----------------------------------------------------------------------
	# Save in TXT format
	# -Enabled Blocks only
	# -Clened from bCNC metadata and comments
	# -Uppercase
	#----------------------------------------------------------------------
	def saveTXT(self, filename):
		txt = open(filename, 'w')
		for block in self.blocks:
			if block.enable:
				for line in block:
					cmds = CNC.parseLine(line)
					if cmds is None: continue
					txt.write("%s\n"%line.upper())
		txt.close()
		return True

	#----------------------------------------------------------------------
	def addBlockFromString(self, name, text):
		if not text: return
		block = Block(name)
		block.extend(text.splitlines())
		self.blocks.append(block)

	#----------------------------------------------------------------------
	# If empty insert a header and a footer
	#----------------------------------------------------------------------
	def headerFooter(self):
		if not self.blocks:
			self.addBlockFromString("Header",self.header)
			self.addBlockFromString("Footer",self.footer)
			return True
		return False

	#----------------------------------------------------------------------
	# Load DXF file into gcode
	#----------------------------------------------------------------------
	def importDXF(self, filename):
		try:
			dxf = DXF(filename,"r")
		except:
			return False
		self.filename = ""

		dxf.readFile()
		dxf.close()

		# prepare dxf file
		dxf.sort()
		dxf.convert2Polylines()
		dxf.expandBlocks()

		#import time; start = time.time()
		empty = len(self.blocks)==0
		if empty: self.addBlockFromString("Header",self.header)

		if CNC.inch:
			units = DXF.INCHES
		else:
			units = DXF.MILLIMETERS

		undoinfo = []
		for name,layer in dxf.layers.items():
			enable = not bool(layer.isFrozen())
			entities = dxf.entities(name)
			if not entities: continue
			self.importEntityPoints(None, entities, name, enable, layer.color())
			path = Path(name)
			path.fromDxf(dxf, entities, units)
			path.removeZeroLength()
			if path.color is None:
				path.color = layer.color()
			if path.color == "#FFFFFF": path.color = None
			opath = path.split2contours()
			if not opath: continue
			while opath:
				li = 0
				llen = 0.0
				for i,p in enumerate(opath):
					if p.length()>llen:
						li = i
						llen = p.length()
				longest = opath.pop(li)

				# Can be time consuming
				if GCode.LOOP_MERGE:
#					print "Loop merge"
					longest.mergeLoops(opath)

				undoinfo.extend(self.importPath(None, longest, None, enable))
#				d = longest.direction()
#				bid = len(self.blocks)-1
#				if d==0:
#					undoinfo.extend(self.addBlockOperationUndo(bid,"O"))
#				elif d==1:
#					undoinfo.extend(self.addBlockOperationUndo(bid,"CW"))
#				elif d==-1:
#					undoinfo.extend(self.addBlockOperationUndo(bid,"CCW"))

			undoinfo.extend(self.importPath(None, opath, None, enable))
#			d = opath.direction()
#			bid = len(self.blocks)-1
#			if d==0:
#				undoinfo.extend(self.addBlockOperationUndo(bid,"O"))
#			elif d==1:
#				undoinfo.extend(self.addBlockOperationUndo(bid,"CW"))
#			elif d==-1:
#				undoinfo.extend(self.addBlockOperationUndo(bid,"CCW"))

		#print "Loading time:", time.time()-start
		if empty: self.addBlockFromString("Footer",self.footer)
		#self.addUndo(undoinfo)
		return True

	#----------------------------------------------------------------------
	# Save in DXF format
	#----------------------------------------------------------------------
	def saveDXF(self, filename):
		try:
			dxf = DXF(filename,"w")
		except:
			return False
		if CNC.inch:
			dxf.units = DXF.INCHES
		else:
			dxf.units = DXF.MILLIMETERS
		dxf.writeHeader()
		for block in self.blocks:
			name = block.name()
			if ":" in name: name = name.split(":")[0]
			for line in block:
				cmds = CNC.parseLine(line)
				if cmds is None: continue
				self.cnc.motionStart(cmds)
				if self.cnc.gcode == 1:	# line
					dxf.line(self.cnc.x, self.cnc.y, self.cnc.xval, self.cnc.yval, name)
				elif self.cnc.gcode in (2,3):	# arc
					xc,yc = self.cnc.motionCenter()
					sphi = math.atan2(self.cnc.y-yc,    self.cnc.x-xc)
					ephi = math.atan2(self.cnc.yval-yc, self.cnc.xval-xc)
					if self.cnc.gcode==2:
						if ephi<=sphi+1e-10: ephi += 2.0*math.pi
						dxf.arc(xc,yc,self.cnc.rval, math.degrees(ephi), math.degrees(sphi),name)
					else:
						if ephi<=sphi+1e-10: ephi += 2.0*math.pi
						dxf.arc(xc,yc,self.cnc.rval, math.degrees(sphi), math.degrees(ephi),name)
				self.cnc.motionEnd()
		dxf.writeEOF()
		dxf.close()
		return True

	#----------------------------------------------------------------------
	# Import POINTS from entities
	#----------------------------------------------------------------------
	def importEntityPoints(self, pos, entities, name, enable=True, color=None):
		undoinfo = []
		i = 0
		while i<len(entities):
			if entities[i].type != "POINT":
				i += 1
				continue

			block = Block("%s [P]"%(name))
			block.enable = enable

			block.color = entities[i].color()
			if block.color is None:
				block.color = color

			x,y = entities[i].start()
			block.append("g0 %s %s"%(self.fmt("x",x,7),self.fmt("y",y,7)))
			block.append(CNC.zenter(self.cnc["surface"]))
			block.append(CNC.zsafe())
			undoinfo.append(self.addBlockUndo(pos,block))
			if pos is not None: pos += 1
			del entities[i]

		return undoinfo

	#----------------------------------------------------------------------
	# convert a block to path
	#----------------------------------------------------------------------
	def toPath(self, bid):
		block = self.blocks[bid]
		paths = []
		path = Path(block.name())
		self.initPath(bid)
		start = Vector(self.cnc.x, self.cnc.y)

		# get only first path that enters the surface
		# ignore the deeper ones
		z1st = None
		for line in block:
			cmds = CNC.parseLine(line)
			if cmds is None: continue
			self.cnc.motionStart(cmds)
			end = Vector(self.cnc.xval, self.cnc.yval)
			if self.cnc.gcode == 0:		# rapid move (new block)
				if path:
					paths.append(path)
					path = Path(block.name())
			elif self.cnc.gcode == 1:	# line
				if z1st is None: z1st = self.cnc.zval
				if (self.cnc.dx != 0.0 or self.cnc.dy != 0.0) and abs(self.cnc.zval-z1st)<0.0001:
					path.append(Segment(1, start, end))
			elif self.cnc.gcode in (2,3):	# arc
				if z1st is None: z1st = self.cnc.zval
				if abs(self.cnc.z-z1st)<0.0001:
					xc,yc = self.cnc.motionCenter()
					center = Vector(xc,yc)
					path.append(Segment(self.cnc.gcode, start,end, center))
			self.cnc.motionEnd()
			start = end
		if path: paths.append(path)
		return paths

	#----------------------------------------------------------------------
	# create a block from Path
	#----------------------------------------------------------------------
	def fromPath(self, path, block=None, z=None, entry=True, exit=True):
		if block is None:
			if isinstance(path, Path):
				block = Block(path.name)
			else:
				block = Block(path[0].name)

		def addSegment(segment):
			x,y = segment.end
			if segment.type == Segment.LINE:
				x,y = segment.end
				block.append("g1 %s %s"%(self.fmt("x",x,7),self.fmt("y",y,7)))
			elif segment.type in (Segment.CW, Segment.CCW):
				ij = segment.center - segment.start
				if abs(ij[0])<1e-5: ij[0] = 0.
				if abs(ij[1])<1e-5: ij[1] = 0.
				block.append("g%d %s %s %s %s" % \
					(segment.type,
					 self.fmt("x",x,7), self.fmt("y",y,7),
					 self.fmt("i",ij[0],7),self.fmt("j",ij[1],7)))

		if isinstance(path, Path):
			x,y = path[0].start
			if z is None: z = self.cnc["surface"]
			if entry:
				block.append("g0 %s %s"%(self.fmt("x",x,7),self.fmt("y",y,7)))
			block.append(CNC.zenter(z))
			setfeed = True
			prevInside = None
			for segment in path:
				if prevInside is not segment._inside:
					if segment._inside is None:
						block.append(CNC.zenter(z))
						setfeed = True
					elif segment._inside.z > z:
						block.append(CNC.zexit(segment._inside.z))
						setfeed = True
					prevInside = segment._inside
				addSegment(segment)
#				x,y = segment.end
#				if segment.type == Segment.LINE:
#					x,y = segment.end
#					block.append("g1 %s %s"%(self.fmt("x",x,7),self.fmt("y",y,7)))
#				elif segment.type in (Segment.CW, Segment.CCW):
#					ij = segment.center - segment.start
#					if abs(ij[0])<1e-5: ij[0] = 0.
#					if abs(ij[1])<1e-5: ij[1] = 0.
#					block.append("g%d %s %s %s %s" % \
#						(segment.type,
#						 self.fmt("x",x,7), self.fmt("y",y,7),
#						 self.fmt("i",ij[0],7),self.fmt("j",ij[1],7)))

				if setfeed:
					block[-1] += " %s"%(self.fmt("f",self.cnc["cutfeed"]))
					setfeed = False
			if exit:
				block.append(CNC.zsafe())
		else:
			for p in path:
				self.fromPath(p, block)
		return block

	#----------------------------------------------------------------------
	# Import paths as block
	# return ids of blocks added in newblocks list if declared
	#----------------------------------------------------------------------
	def importPath(self, pos, paths, newblocks=None, enable=True, multiblock=True):
		undoinfo = []
		if isinstance(paths,Path):
			block = self.fromPath(paths)
			block.enable = enable
			block.color  = paths.color
			undoinfo.append(self.addBlockUndo(pos,block))
			if newblocks is not None: newblocks.append(pos)
		else:
			block = None
			for path in paths:
				if block is None:
					block = Block(path.name)
				block = self.fromPath(path, block)
				if multiblock:
					block.enable = enable
					undoinfo.append(self.addBlockUndo(pos,block))
					if newblocks is not None: newblocks.append(pos)
					if pos is not None: pos += 1
					block = None
			if not multiblock:
				block.enable = enable
				undoinfo.append(self.addBlockUndo(pos,block))
				if newblocks is not None: newblocks.append(pos)
		return undoinfo

	#----------------------------------------------------------------------
	# Check if a new version exists
	#----------------------------------------------------------------------
	def checkFile(self):
		try:
			return os.stat(self.filename).st_mtime > self._lastModified
		except:
			return False

	#----------------------------------------------------------------------
	def fmt(self, c, v, d=None): return self.cnc.fmt(c,v,d)

	#----------------------------------------------------------------------
	def _trim(self):
		if not self.blocks: return
		# Delete last block if empty
		last = self.blocks[-1]
		if len(last)==1 and len(last[0])==0: del last[0]
		if len(self.blocks[-1])==0:
			self.blocks.pop()

	#----------------------------------------------------------------------
	# Undo/Redo operations
	#----------------------------------------------------------------------
	def undo(self):
		#print ">u>",self.undoredo.undoText()
		self.undoredo.undo()

	#----------------------------------------------------------------------
	def redo(self):
		#print ">r>",self.undoredo.redoText()
		self.undoredo.redo()

	#----------------------------------------------------------------------
	def addUndo(self, undoinfo, msg=""):
		if isinstance(undoinfo,list):
			if len(undoinfo)==1:
				self.undoredo.addUndo(undoinfo[0])
			else:
				self.undoredo.addUndo(undo.createListUndo(undoinfo,msg))
		elif undoinfo is not undo.NullUndo:
			self.undoredo.addUndo(undoinfo)
		self._modified = True

	#----------------------------------------------------------------------
	def canUndo(self):	return self.undoredo.canUndo()
	def canRedo(self):	return self.undoredo.canRedo()

	#----------------------------------------------------------------------
	# Append a new tab
	#----------------------------------------------------------------------
	def addTabUndo(self, bid, tid, tab):
		block = self.blocks[bid]
		if tid<0 or tid>=len(block.tabs):
			undoinfo = (self.delTabUndo, bid, len(block.tabs))
			block.tabs.append(tab)
		else:
			undoinfo = (self.delTabUndo, bid, tid)
			block.tabs.insert(tid, tab)
		return undoinfo

	#----------------------------------------------------------------------
	def delTabUndo(self, bid, tid):
		block = self.blocks[bid]
		undoinfo = (self.addTabUndo, bid, tid, block.tabs[tid])
		del block.tabs[tid]
		return undoinfo

	#----------------------------------------------------------------------
	def tabSetUndo(self, bid, tid, params):
		tab = self.blocks[bid].tabs[tid]
		undoinfo = (self.tabSetUndo, bid, tid, tab.save())
		tab.restore(params)
		return undoinfo

	#----------------------------------------------------------------------
	# Change all lines in editor
	#----------------------------------------------------------------------
	def setLinesUndo(self, lines):
		undoinfo = (self.setLinesUndo, list(self.lines()))
		# Delete all blocks and create new ones
		del self.blocks[:]
		self.cnc.initPath()
		self._blocksExist = False
		for line in lines: self._addLine(line)
		self._trim()
		return undoinfo

	#----------------------------------------------------------------------
	def setAllBlocksUndo(self, blocks=[]):
		undoinfo = [self.setAllBlocksUndo, self.blocks]
		self.blocks = blocks
		return undoinfo

	#----------------------------------------------------------------------
	# Change a single line in a block
	#----------------------------------------------------------------------
	def setLineUndo(self, bid, lid, line):
		undoinfo = (self.setLineUndo, bid, lid, self.blocks[bid][lid])
		self.blocks[bid][lid] = line
		return undoinfo

	#----------------------------------------------------------------------
	# Insert a new line into block
	#----------------------------------------------------------------------
	def insLineUndo(self, bid, lid, line):
		undoinfo = (self.delLineUndo, bid, lid)
		block = self.blocks[bid]
		if lid>=len(block):
			block.append(line)
		else:
			block.insert(lid, line)
		return undoinfo

	#----------------------------------------------------------------------
	# Clone line inside a block
	#----------------------------------------------------------------------
	def cloneLineUndo(self, bid, lid):
		return self.insLineUndo(bid, lid, self.blocks[bid][lid])

	#----------------------------------------------------------------------
	# Delete line from block
	#----------------------------------------------------------------------
	def delLineUndo(self, bid, lid):
		block = self.blocks[bid]
		undoinfo = (self.insLineUndo, bid, lid, block[lid])
		del block[lid]
		return undoinfo

	#----------------------------------------------------------------------
	# Add a block
	#----------------------------------------------------------------------
	def addBlockUndo(self, bid, block):
		if bid is None: bid = len(self.blocks)
		undoinfo = (self.delBlockUndo, bid)
		if bid>=len(self.blocks):
			self.blocks.append(block)
		else:
			self.blocks.insert(bid, block)
		return undoinfo

	#----------------------------------------------------------------------
	# Clone a block
	#----------------------------------------------------------------------
	def cloneBlockUndo(self, bid, pos=None):
		if pos is None: pos = bid
		return self.addBlockUndo(pos, Block(self.blocks[bid]))

	#----------------------------------------------------------------------
	# Delete a whole block
	#----------------------------------------------------------------------
	def delBlockUndo(self, bid):
		lines = [x for x in self.blocks[bid]]
		block = self.blocks.pop(bid)
		undoinfo = (self.addBlockUndo, bid, block)
		return undoinfo

	#----------------------------------------------------------------------
	# Insert a list of other blocks from another gcode file probably
	#----------------------------------------------------------------------
	def insBlocksUndo(self, bid, blocks):
		if bid is None or bid >= len(self.blocks):
			bid = len(self.blocks)
		undoinfo = ("Insert blocks", self.delBlocksUndo, bid, bid+len(blocks))
		self.blocks[bid:bid] = blocks
		return undoinfo

	#----------------------------------------------------------------------
	# Delete a range of blocks
	#----------------------------------------------------------------------
	def delBlocksUndo(self, from_, to_):
		blocks = self.blocks[from_:to_]
		undoinfo = ("Delete blocks", self.insBlocksUndo, from_, blocks)
		del self.blocks[from_:to_]
		return undoinfo

	#----------------------------------------------------------------------
	# Insert blocks and push the undo info
	#----------------------------------------------------------------------
	def insBlocks(self, bid, blocks, msg=""):
		if self.headerFooter():	# just in case
			bid = 1
		self.addUndo(self.insBlocksUndo(bid, blocks), msg)

	#----------------------------------------------------------------------
	# Set block expand
	#----------------------------------------------------------------------
	def setBlockExpandUndo(self, bid, expand):
		undoinfo = (self.setBlockExpandUndo, bid, self.blocks[bid].expand)
		self.blocks[bid].expand = expand
		return undoinfo

	#----------------------------------------------------------------------
	# Set block state
	#----------------------------------------------------------------------
	def setBlockEnableUndo(self, bid, enable):
		undoinfo = (self.setBlockEnableUndo, bid, self.blocks[bid].enable)
		self.blocks[bid].enable = enable
		return undoinfo

	#----------------------------------------------------------------------
	# Set block color
	#----------------------------------------------------------------------
	def setBlockColorUndo(self, bid, color):
		undoinfo = (self.setBlockColorUndo, bid, self.blocks[bid].color)
		self.blocks[bid].color = color
		return undoinfo

	#----------------------------------------------------------------------
	# Swap two blocks
	#----------------------------------------------------------------------
	def swapBlockUndo(self, a, b):
		undoinfo = (self.swapBlockUndo, a, b)
		tmp = self.blocks[a]
		self.blocks[a] = self.blocks[b]
		self.blocks[b] = tmp
		return undoinfo

	#----------------------------------------------------------------------
	# Move block from location src to location dst
	#----------------------------------------------------------------------
	def moveBlockUndo(self, src, dst):
		if src == dst: return undo.NullUndo
		undoinfo = (self.moveBlockUndo, dst, src)
		if dst > src:
			self.blocks.insert(dst-1, self.blocks.pop(src))
		else:
			self.blocks.insert(dst, self.blocks.pop(src))
		return undoinfo

	#----------------------------------------------------------------------
	# Invert selected blocks
	#----------------------------------------------------------------------
	def invertBlocksUndo(self, blocks):
		undoinfo = []
		first = 0
		last  = len(blocks)-1
		while first < last:
			undoinfo.append(self.swapBlockUndo(blocks[first],blocks[last]))
			first += 1
			last  -= 1
		return undoinfo

	#----------------------------------------------------------------------
	# Move block upwards
	#----------------------------------------------------------------------
	def orderUpBlockUndo(self, bid):
		if bid==0: return undo.NullUndo
		undoinfo = (self.orderDownBlockUndo, bid-1)
		# swap with the block above
		before      = self.blocks[bid-1]
		self.blocks[bid-1] = self.blocks[bid]
		self.blocks[bid]   = before
		return undoinfo

	#----------------------------------------------------------------------
	# Move block downwards
	#----------------------------------------------------------------------
	def orderDownBlockUndo(self, bid):
		if bid>=len(self.blocks)-1: return undo.NullUndo
		undoinfo = (self.orderUpBlockUndo, bid+1)
		# swap with the block below
		after       = self[bid+1]
		self[bid+1] = self[bid]
		self[bid]   = after
		return undoinfo

	#----------------------------------------------------------------------
	# Insert block lines
	#----------------------------------------------------------------------
	def insBlockLinesUndo(self, bid, lines):
		undoinfo = (self.delBlockLinesUndo, bid)
		block = Block()
		for line in lines:
			block.append(line)
		self.blocks.insert(bid, block)
		return undoinfo

	#----------------------------------------------------------------------
	# Delete a whole block lines
	#----------------------------------------------------------------------
	def delBlockLinesUndo(self, bid):
		lines = [x for x in self.blocks[bid]]
		undoinfo = (self.insBlockLinesUndo, bid, lines) #list(self.blocks[bid])[:])
		del self.blocks[bid]
		return undoinfo

	#----------------------------------------------------------------------
	# Set Block name
	#----------------------------------------------------------------------
	def setBlockNameUndo(self, bid, name):
		undoinfo = (self.setBlockNameUndo, bid, self.blocks[bid]._name)
		self.blocks[bid]._name = name
		return undoinfo

	#----------------------------------------------------------------------
	# Add an operation code in the name as [drill, cut, in/out...]
	#----------------------------------------------------------------------
	def addBlockOperationUndo(self, bid, operation, remove=None):
		undoinfo = (self.setBlockNameUndo, bid, self.blocks[bid]._name)
		self.blocks[bid].addOperation(operation, remove)
		return undoinfo

	#----------------------------------------------------------------------
	# Replace the lines of a block
	#----------------------------------------------------------------------
	def setBlockLinesUndo(self, bid, lines):
		block = self.blocks[bid]
		undoinfo = (self.setBlockLinesUndo, bid, block[:])
		del block[:]
		block.extend(lines)
		return undoinfo

	#----------------------------------------------------------------------
	# Move line upwards
	#----------------------------------------------------------------------
	def orderUpLineUndo(self, bid, lid):
		if lid==0: return undo.NullUndo
		block = self.blocks[bid]
		undoinfo = (self.orderDownLineUndo, bid, lid-1)
		block.insert(lid-1, block.pop(lid))
		return undoinfo

	#----------------------------------------------------------------------
	# Move line downwards
	#----------------------------------------------------------------------
	def orderDownLineUndo(self, bid, lid):
		block = self.blocks[bid]
		if lid>=len(block)-1: return undo.NullUndo
		undoinfo = (self.orderUpLineUndo, bid, lid+1)
		block.insert(lid+1, block.pop(lid))
		return undoinfo

	#----------------------------------------------------------------------
	# Expand block with autolevel information
	#----------------------------------------------------------------------
	def autolevelBlock(self, block):
		new = []
		autolevel = not self.probe.isEmpty()
		for line in block:
			newcmd = []
			cmds = CNC.compileLine(line)
			if cmds is None:
				new.append(line)
				continue
			elif isinstance(cmds,str) or isinstance(cmds,unicode):
				cmds = CNC.breakLine(cmds)
			else:
				new.append(line)
				continue

			self.cnc.motionStart(cmds)
			if autolevel and self.cnc.gcode in (0,1,2,3) and self.cnc.mval==0:
				xyz = self.cnc.motionPath()
				if not xyz:
					# while auto-levelling, do not ignore non-movement
					# commands, just append the line as-is
					new.append(line)
				else:
					extra = ""
					for c in cmds:
						if c[0].upper() not in ('G','X','Y','Z','I','J','K','R'):
							extra += c
					x1,y1,z1 = xyz[0]
					if self.cnc.gcode == 0:
						g = 0
					else:
						g = 1
					for x2,y2,z2 in xyz[1:]:
						for x,y,z in self.probe.splitLine(x1,y1,z1,x2,y2,z2):
							new.append("G%d%s%s%s%s"%\
								(g,
								 self.fmt('X',x/self.cnc.unit),
								 self.fmt('Y',y/self.cnc.unit),
								 self.fmt('Z',z/self.cnc.unit),
								 extra))
							extra = ""
						x1,y1,z1 = x2,y2,z2
				self.cnc.motionEnd()
			else:
				self.cnc.motionEnd()
				new.append(line)
		return new

	#----------------------------------------------------------------------
	# Execute autolevel on selected blocks
	#----------------------------------------------------------------------
	def autolevel(self, items):
		undoinfo = []
		operation = "autolevel"
		for bid in items:
			block = self.blocks[bid]
			if block.name() in ("Header", "Footer"): continue
			if not block.enable: continue
			lines = self.autolevelBlock(block)
			undoinfo.append(self.addBlockOperationUndo(bid, operation))
			undoinfo.append(self.setBlockLinesUndo(bid, lines))
		if undoinfo: self.addUndo(undoinfo)

	#----------------------------------------------------------------------
	# Merge or split blocks depending on motion
	#
	# Each block should start with a rapid move and end with a rapid move
	#----------------------------------------------------------------------
#	def correctBlocks(self):
#		# Working in place tricky
#		bid = 0	# block index
#		while bid < len(self.blocks):
#			block = self.blocks[bid]
#			li = 0	# line index
#			prefix = True
#			suffix = False
#			lastg0 = None
#			while li < len(block):
#				line = block[li]
#				cmds = CNC.parseLine(line)
#				if cmds is None:
#					li += 1
#					continue
#
#				self.cnc.motionStart(cmds)
#
#				# move
#				if self.gcode in (1,2,3):
#					if prefix is None: prefix = li-1
#
#				# rapid movement
#				elif self.gcode == 0:
#					lastg0 = li
#					if prefix is not None: suffix = li
#
#					# moving up = end of block
#					if self.cnc.dz > 0.0:
#						if suffix:
#							# Move all subsequent lines to a new block
#							#self.blocks.append(Block())
#							pass
#				self.cnc.motionEnd()

	#----------------------------------------------------------------------
	# Start a new iterator
	#----------------------------------------------------------------------
#	def __iter__(self):
#		self._iter = 0	#self._iter_start
#		self._iter_block = self.blocks[self._iter]
#		self._iter_block_i = 0
#		self._iter_end   = len(self.blocks)
#		return self
#
#	#----------------------------------------------------------------------
#	# Next iterator item
#	#----------------------------------------------------------------------
#	def next(self):
#		if self._iter >= self._iter_end: raise StopIteration()
#
#		while self._iter_block_i >= len(self._iter_block):
#			self._iter += 1
#			if self._iter >= self._iter_end: raise StopIteration()
#			self._iter_block = self.blocks[self._iter]
#			self._iter_block_i = 0
#
#		item = self._iter_block[self._iter_block_i]
#		self._iter_block_i += 1
#		return item

	#----------------------------------------------------------------------
	# Return string representation of whole file
	#----------------------------------------------------------------------
	def __repr__(self):
		return "\n".join(list(self.lines()))

	#----------------------------------------------------------------------
	# Iterate over the items
	#----------------------------------------------------------------------
	def iterate(self, items):
		for bid,lid in items:
			if lid is None:
				block = self.blocks[bid]
				for i in block.tabs:
					yield bid,i
				for i in range(len(block)):
					yield bid,i
			else:
				yield bid,lid

	#----------------------------------------------------------------------
	# Iterate over all lines
	#----------------------------------------------------------------------
	def lines(self):
		for block in self.blocks:
			for line in block:
				yield line

	#----------------------------------------------------------------------
	# initialize cnc path based on block bid
	#----------------------------------------------------------------------
	def initPath(self, bid=0):
		if bid == 0:
			self.cnc.initPath()
		else:
			# Use the ending point of the previous block
			# since the starting (sxyz is after the rapid motion)
			block = self.blocks[bid-1]
			self.cnc.initPath(block.ex, block.ey, block.ez)

	#----------------------------------------------------------------------
	# Move blocks/lines up
	#----------------------------------------------------------------------
	def orderUp(self, items):
		sel = []	# new selection
		undoinfo = []
		for bid,lid in items:
			if isinstance(lid,int):
				undoinfo.append(self.orderDownLineUndo(bid,lid))
				sel.append((bid, lid-1))
			elif lid is None:
				undoinfo.append(self.orderUpBlockUndo(bid))
				if bid==0:
					return items
				else:
					sel.append((bid-1,None))
		self.addUndo(undoinfo,"Move Up")
		return sel

	#----------------------------------------------------------------------
	# Move blocks/lines down
	#----------------------------------------------------------------------
	def orderDown(self, items):
		sel = []	# new selection
		undoinfo = []
		for bid,lid in reversed(items):
			if isinstance(lid,int):
				undoinfo.append(self.orderDownLineUndo(bid,lid))
				sel.append((bid,lid+1))
			elif lid is None:
				undoinfo.append(self.orderDownBlockUndo(bid))
				if bid>=len(self.blocks)-1:
					return items
				else:
					sel.append((bid+1,None))
		self.addUndo(undoinfo,"Move Down")
		sel.reverse()
		return sel

	#----------------------------------------------------------------------
	# Peck distance
	# Target depth
	# Depth increment
	# Retract height=safe height
	#----------------------------------------------------------------------
	def drill(self, items, depth=None, peck=None, dwell=None, distance=None, number=0):
		# find the penetration points and drill
		# skip all g1 movements on the horizontal plane
		if depth is None: depth = self.cnc["surface"]-self.cnc["thickness"]
		if depth < self.cnc["surface"]-self.cnc["thickness"] or depth > self.cnc["surface"]:
			return  "ERROR: Drill depth %g outside stock surface: %g .. %g\n" \
				"Please change stock surface in Tools->Stock or drill depth." \
				%(depth, self.cnc["surface"], self.cnc["surface"]-self.cnc["thickness"])
		if abs(depth - (self.cnc["surface"]-self.cnc["thickness"])) < 1e-7:
			opname = "drill"
		else:
			opname = "drill:%g"%(depth)

		undoinfo = []

		def drillHole(lines):
			# drill point
			if peck is None:
				lines.append(CNC.zenter(depth))
				lines.append(CNC.zsafe())
			else:
				z = self.cnc["surface"]
				while z>depth:
					z = max(z-peck, depth)
					lines.append(CNC.zenter(z))
					lines.append(CNC.zsafe())
					if dwell:
						lines.append("g4 %s"%(self.fmt("p",dwell)))

		for bid in items:
			block = self.blocks[bid]
			if block.name() in ("Header", "Footer"): continue
			block.enable = True

			# construct new name
			undoinfo.append(self.addBlockOperationUndo(bid, opname))

			# 1st detect limits of first pass
			self.initPath(bid)
			self.cnc.z = self.cnc.zval = 1000.0
			lines = []
			if distance is None and number==0:
				for i,line in enumerate(block):
					cmds = CNC.parseLine(line)
					if cmds is None:
						lines.append(line)
						continue
					self.cnc.motionStart(cmds)
					if self.cnc.dz<0.0:
						drillHole(lines)
					elif self.cnc.dz>0.0:
						# retract
						pass
					elif self.cnc.gcode == 0:
						# add all rapid movements
						lines.append(line)
					elif self.cnc.gcode == 1:
						# ignore normal movements
						pass
					self.cnc.motionEnd()
			else:
				for path in self.toPath(bid):
					length = path.length()
					if number>0:
						distance = length / float(number)
					s = 0.0			# running length
					P = path[0].start
					lines.append("g0 %s %s"%(self.fmt("x",P[0]),self.fmt("y",P[1])))
					drillHole(lines)
					for segment in path:
						l = segment.length()
						# if we haven't reach 'distance'
						if s+l < distance:
							s += l
							continue
						n = 0
						while True:
							n += 1
							remain = n*distance - s
							if remain > l:
								s = distance-(remain-l)
								break
							if segment.type == Segment.LINE:
								P = segment.start + (remain/l)*segment.AB
							else:
								if segment.type == Segment.CW:
									phi = segment.startPhi - remain / segment.radius
								else:
									phi = segment.startPhi + remain / segment.radius
								P = Vector(segment.center[0] + segment.radius*math.cos(phi),
									   segment.center[1] + segment.radius*math.sin(phi))
							lines.append("g0 %s %s"%(self.fmt("x",P[0]),self.fmt("y",P[1])))
							drillHole(lines)
			undoinfo.append(self.setBlockLinesUndo(bid,lines))
		self.addUndo(undoinfo)

	#----------------------------------------------------------------------
	# Perform a cut on a path an add it to block
	# @param newblock O	block to add the cut paths
	# @param block	I	existing block
	# @param path	I	path to cut
	# @param z	I	starting z surface
	# @param depth	I	ending depth
	# @param stepz	I	stepping in z
	#----------------------------------------------------------------------
	def cutPath(self, newblock, block, path, z, depth, stepz):
		closed = path.isClosed()
		entry  = True
		exit   = False

		# Mark in which tab we are inside
		if block.tabs:
			# Mark everything as outside
			for tab in block.tabs:
				tab.create(CNC.vars["diameter"])
				tab.split(path)

		while z > depth:
			z = max(z-stepz, depth)
			if not closed:
				# on open paths always enter exit
				entry = exit = True
			elif abs(z-depth)<1e-7:
				# last pass
				exit = True

			self.fromPath(path, newblock, z, entry, exit)
			entry = False
		return newblock

	#----------------------------------------------------------------------
	# Close paths by joining end with start with a line segment
	#----------------------------------------------------------------------
	def close(self, items):
		undoinfo = []
		for bid in items:
			block = self.blocks[bid]
			if block.name() in ("Header", "Footer"): continue
			undoinfo.append(self.insLineUndo(bid, MAXINT,
					self.cnc.gline(block.sx, block.sy)))
		self.addUndo(undoinfo)

	#----------------------------------------------------------------------
	# Create a cut my replicating the initial top-only path multiple times
	# until the maximum height
	#----------------------------------------------------------------------
	def cut(self, items, depth=None, stepz=None, surface=None, feed=None, feedz=None, cutFromTop=False):
		if surface is None: surface = self.cnc["surface"]
		if stepz is None:   stepz = self.cnc["stepz"]
		if depth is None:   depth = surface - self.cnc["thickness"]

		# override temporarily the feed if needed
		if feed is not None: # swap feed with cnc[cutfeed]
			self.cnc["cutfeed"],feed   = feed, self.cnc["cutfeed"]
		if feedz is not None:
			self.cnc["cutfeedz"],feedz = feedz, self.cnc["cutfeedz"]

		if surface > self.cnc["surface"]:
			return "ERROR: Starting cut height is higher than stock surface. " \
				"Please change stock surface in Tools->Stock or cut depth."
		if depth < self.cnc["surface"]-self.cnc["thickness"] or depth > self.cnc["surface"]:
			return  "ERROR: Cut depth %g outside stock surface: %g .. %g\n" \
				"Please change stock surface in Tools->Stock or cut depth." \
				%(depth, self.cnc["surface"], self.cnc["surface"]-self.cnc["thickness"])
		if abs(depth - (self.cnc["surface"]-self.cnc["thickness"])) < 1e-7:
			opname = "cut"
		else:
			opname = "cut:%g"%(depth)
		stepz = abs(stepz)
		undoinfo = []
		for bid in items:
			block = self.blocks[bid]
			if block.name() in ("Header", "Footer"): continue
			block.enable = True
			newpath = []
			newblock = Block(block.name())
			for path in self.toPath(bid):
				if cutFromTop:
					self.cutPath(newblock, block, path, surface + stepz, depth, stepz)
				else:
					self.cutPath(newblock, block, path, surface, depth, stepz)
			if newblock:
				undoinfo.append(self.addBlockOperationUndo(bid, opname))
				undoinfo.append(self.setBlockLinesUndo(bid, newblock))
		self.addUndo(undoinfo)

		# restore feed
		if feed  is not None: self.cnc["cutfeed"]  = feed
		if feedz is not None: self.cnc["cutfeedz"] = feedz

	#----------------------------------------------------------------------
	# Create tabs to selected blocks
	# @param ntabs	number of tabs
	# @param dtabs	distance between tabs
	# @param dx	width of tabs
	# @param dy	depth of tabs
	# @param z	height of tabs
	#----------------------------------------------------------------------
	def createTabs(self, items, ntabs, dtabs, dx, dy, z):
		undoinfo = []
		if ntabs==0 and dtabs==0: return
		for bid in items:
			block = self.blocks[bid]
			if block.name() in ("Header", "Footer"): continue
			for path in self.toPath(bid):
				length = path.length()
				d = max(length / float(ntabs), dtabs)
				# running length
				s = d/2.	# start from half distance to add first tab
				for segment in path:
					l = segment.length()
					# if we haven't reach d
					if s+l < d:
						s += l
						continue
					n = 0
					while True:
						n += 1
						remain = n*d - s
						if remain > l:
							s = d-(remain-l)
							break
						if segment.type == Segment.LINE:
							P = segment.start + (remain/l)*segment.AB
						else:
							if segment.type == Segment.CW:
								phi = segment.startPhi - remain / segment.radius
							else:
								phi = segment.startPhi + remain / segment.radius
							P = Vector(segment.center[0] + segment.radius*math.cos(phi),
								   segment.center[1] + segment.radius*math.sin(phi))
						tab = Tab(P[0],P[1],dx,dy,z)
						undoinfo.append(self.addTabUndo(bid,0,tab))
		self.addUndo(undoinfo)

	#----------------------------------------------------------------------
	# Reverse direction of cut
	#----------------------------------------------------------------------
	def reverse(self, items):
		undoinfo = []
		operation = "reverse"
		remove = ["cut","climb","conventional"]
		for bid in items:
			if self.blocks[bid].name() in ("Header", "Footer"): continue
			newpath = []
			for path in self.toPath(bid):
				path.invert()
				newpath.append(path)
			if newpath:
				block = self.fromPath(newpath)
				undoinfo.append(self.addBlockOperationUndo(bid, operation, remove))
				undoinfo.append(self.setBlockLinesUndo(bid, block))
		self.addUndo(undoinfo)

	#----------------------------------------------------------------------
	def cutDirection(self, items, direction=1):
		undoinfo = []
		if direction==1:
			operation = "conventional"
		else:
			operation = "climb"
		remove = ["cut","reverse","climb","conventional"]
		for bid in items:
			if self.blocks[bid].name() in ("Header", "Footer"): continue
			newpath = []
			for path in self.toPath(bid):
				if path._direction(path.isClosed())==direction: path.invert()
				newpath.append(path)
			if newpath:
				block = self.fromPath(newpath)
				undoinfo.append(self.addBlockOperationUndo(bid, operation,remove))
				undoinfo.append(self.setBlockLinesUndo(bid, block))
		self.addUndo(undoinfo)

	#----------------------------------------------------------------------
	# Return information for a block
	# return XXX
	#----------------------------------------------------------------------
	def info(self, bid):
		block = self.blocks[bid]
		paths = self.toPath(bid)
		if not paths:
			return None, 1
		if len(paths)>1:
			closed = paths[0].isClosed()
			return len(paths), paths[0]._direction(closed)
		else:
			closed = paths[0].isClosed()
			return int(closed), paths[0]._direction(closed)

	#----------------------------------------------------------------------
	# make a profile on block
	# offset +/- defines direction = tool/2
	# return new blocks inside the blocks list
	#----------------------------------------------------------------------
	def profile(self, blocks, offset, overcut=False, name=None):
		undoinfo = []
		msg = ""
		newblocks = []
		for bid in reversed(blocks):
			if self.blocks[bid].name() in ("Header", "Footer"): continue
			newpath = []
			for path in self.toPath(bid):
				if name is not None:
					newname = Block.operationName(path.name, name)
				elif offset>0:
					newname = Block.operationName(path.name, "out")
				else:
					newname = Block.operationName(path.name, "in")

				if not path.isClosed():
					m = "Path: '%s' is OPEN"%(path.name)
					if m not in msg:
						if msg: msg += "\n"
						msg += m

#				print "ORIGINAL\n",path
				# Remove tiny segments
				path.removeZeroLength(abs(offset)/100.)
				# Convert very small arcs to lines
				path.convert2Lines(abs(offset)/10.)
				D = path.direction()
#				print "Path Direction:",D
				if D==0: D=1
#				print "ZERO\n",path
				opath = path.offset(D*offset, newname)
#				print "OFFSET\n",opath
				if opath:
					opath.intersectSelf()
#					print "INTERSECT\n",opath
					opath.removeExcluded(path, D*offset)
#					print "EXCLUDE\n",opath
					opath.removeZeroLength(abs(offset)/100.)
#					print "REMOVE\n",opath
				opath = opath.split2contours()
				if opath:
					if overcut:
						for p in opath:
							p.overcut(D*offset)
					newpath.extend(opath)
			if newpath:
				# remember length to shift all new blocks the are inserted before
				before = len(newblocks)
				undoinfo.extend(self.importPath(bid+1, newpath, newblocks, True, False))
				new = len(newblocks)-before
				for i in range(before):
					newblocks[i] += new
				self.blocks[bid].enable = False
		self.addUndo(undoinfo)

		# return new blocks inside the blocks list
		del blocks[:]
		blocks.extend(newblocks)
		return msg

	#----------------------------------------------------------------------
	# Generate a pocket path
	#----------------------------------------------------------------------
	def _pocket(self, path, diameter, stepover, depth):
		#print "_pocket",depth
		if depth>10000: return None
		if depth == 0:
			offset = diameter / 2.0
		else:
			offset = diameter*stepover

#		print
#		print "PATH=",path
		opath = path.offset(offset)

		if not opath: return None

		opath.intersectSelf()
#		print
#		print "INTERSECT=",opath
		opath.removeExcluded(path, offset)
		opath.removeZeroLength(abs(offset)/100.)
		opath = opath.split2contours()

		if not opath: return None

		newpath = []
		for pout in opath:
			pin = self._pocket(pout, diameter, stepover, depth+1)
			if not pin:
				newpath.append(pout)

			#else:	# FIXME
				# 1. Find closest node that we can move with
				#    a straight line without intersecting the path
				# 2. rotate the pout to start from this node
				# 3. join with a normal line
				# else
				# join with a rapid move as a separate path
			elif len(pin)==1:
				# FIXME maybe it is dangerous!!
				# Have to check before making a straight move
				pin[0].join(pout)
				newpath.append(pin[0])

			else:
				# FIXME needs to check if we can go in normal move
				# needs to find the closest segment and rotate
				#pin[-1].join(pout)
				newpath.extend(pin)
				newpath.append(pout)
		return newpath

	#----------------------------------------------------------------------
	# make a pocket on block
	# return new blocks inside the blocks list
	#----------------------------------------------------------------------
	def pocket(self, blocks, diameter, stepover, name):
		undoinfo = []
		msg = ""
		newblocks = []
		for bid in reversed(blocks):
			if self.blocks[bid].name() in ("Header", "Footer"): continue
			newpath = []
			for path in self.toPath(bid):
				if not path.isClosed():
					m = "Path: '%s' is OPEN"%(path.name)
					if m not in msg:
						if msg: msg += "\n"
						msg += m
					path.close()

				# Remove tiny segments
				path.removeZeroLength(abs(diameter)/100.)
				# Convert very small arcs to lines
				path.convert2Lines(abs(diameter)/10.)

				D = path.direction()
				if D==0: D=1
				if name is None:
					path.name = Block.operationName(path.name, "pocket")
				else:
					path.name = Block.operationName(path.name, name)

				newpath.extend(self._pocket(path, -D*diameter, stepover, 0))

			if newpath:
				# remember length to shift all new blocks
				# the are inserted before
				before = len(newblocks)
				undoinfo.extend(self.importPath(bid+1, newpath,
					newblocks, True, False))
				new = len(newblocks)-before
				for i in range(before):
					newblocks[i] += new
				self.blocks[bid].enable = False
		self.addUndo(undoinfo)

		# return new blocks inside the blocks list
		del blocks[:]
		blocks.extend(newblocks)
		return msg

	#----------------------------------------------------------------------
	# draw a hole (circle with radius)
	#----------------------------------------------------------------------
	def hole(self, bid, radius):
		block = self.blocks[bid]

		# Find starting location
		self.initPath(bid)
		for i,line in enumerate(block):
			cmds = CNC.parseLine(line)
			if cmds is None: continue
			self.cnc.motionStart(cmds)
			self.cnc.motionEnd()

		# FIXME doesn't work

		# New lines to append
		pos = lid+1
		block.insert(pos, "g0 %s"%(self.fmt("x",self.cnc.x+radius)))
		pos += 1
		block.insert(pos, "g1 %s"%(self.fmt("z",-0.001)))
		pos += 1
		block.insert(pos, "g2 %s"%(self.fmt("i",-radius)))
		pos += 1

	#----------------------------------------------------------------------
	# Modify the lines according to the supplied function and arguments
	#----------------------------------------------------------------------
	def process(self, items, func, tabFunc, *args):
		undoinfo = []
		old = {}	# Last value
		new = {}	# New value

		for bid,lid in self.iterate(items):
			block = self.blocks[bid]

			if isinstance(lid, Tab) and tabFunc is not None:
				tid = block.tabs.index(lid)
				undoinfo.append(self.tabSetUndo(bid, tid, lid.save()))
				tabFunc(lid, *args)

			elif isinstance(lid, int):
				cmds = CNC.parseLine(block[lid])
				if cmds is None: continue

				# Collect all values
				new.clear()
				for cmd in cmds:
					c = cmd[0].upper()
					try:
						new[c] = old[c] = float(cmd[1:])
					except:
						new[c] = old[c] = 0.0

				# Modify values with func
				if func(new, old, *args):
					# Reconstruct new cmd
					newcmd = []
					present = ""
					for cmd in cmds:
						c = cmd[0].upper()
						present += c
						if c == "M":	# leave unchanged
							newcmd.append(cmd)
						else:
							newcmd.append(self.fmt(cmd[0],new[c]))
					# Append motion commands if not exist and changed
					if 'I' in new or 'J' in new:
						check = "XYZIJK"
					else:
						check = "XYZ"
					for c in check:
						try:
							if c not in present and new[c] != old[c]:
								newcmd.append(self.fmt(c,new[c]))
						except KeyError:
							pass
					undoinfo.append(self.setLineUndo(bid,lid," ".join(newcmd)))

		# FIXME I should add it later, check all functions using it
		self.addUndo(undoinfo)

	#----------------------------------------------------------------------
	# Move position by dx,dy,dz
	#----------------------------------------------------------------------
	def moveFunc(self, new, old, dx, dy, dz):
		changed = False
		if 'X' in new:
			changed = True
			new['X'] += dx
		if 'Y' in new:
			changed = True
			new['Y'] += dy
		if 'Z' in new:
			changed = True
			new['Z'] += dz
		return changed

	#----------------------------------------------------------------------
	def orderLines(self, items, direction):
		if direction == "UP":
			self.orderUp(items)
		elif direction == "DOWN":
			self.orderDown(items)
		else:
			pass

	#----------------------------------------------------------------------
	# Move position by dx,dy,dz
	#----------------------------------------------------------------------
	def moveLines(self, items, dx, dy, dz=0.0):
		return self.process(items, self.moveFunc, Tab.move, dx, dy, dz)

	#----------------------------------------------------------------------
	# Rotate position by c(osine), s(ine) of an angle around center (x0,y0)
	#----------------------------------------------------------------------
	def rotateFunc(self, new, old, c, s, x0, y0):
		if 'X' not in new and 'Y' not in new: return False
		x = getValue('X',new,old)
		y = getValue('Y',new,old)
		new['X'] = c*(x-x0) - s*(y-y0) + x0
		new['Y'] = s*(x-x0) + c*(y-y0) + y0

		if 'I' in new or 'J' in new:
			i = getValue('I',new,old)
			j = getValue('J',new,old)
			new['I'] = c*i - s*j
			new['J'] = s*i + c*j
		return True

	#----------------------------------------------------------------------
	# Transform (rototranslate) position with the following function:
	#	 xn = c*x - s*y + xo
	#	 yn = s*x + c*y + yo
	# it is like the rotate but the rotation center is not defined
	#----------------------------------------------------------------------
	def transformFunc(self, new, old, c, s, xo, yo):
		if 'X' not in new and 'Y' not in new: return False
		x = getValue('X',new,old)
		y = getValue('Y',new,old)
		new['X'] = c*x - s*y + xo
		new['Y'] = s*x + c*y + yo

		if 'I' in new or 'J' in new:
			i = getValue('I',new,old)
			j = getValue('J',new,old)
			new['I'] = c*i - s*j
			new['J'] = s*i + c*j
		return True

	#----------------------------------------------------------------------
	# Rotate items around optional center (on XY plane)
	# ang in degrees (counter-clockwise)
	#----------------------------------------------------------------------
	def rotateLines(self, items, ang, x0=0.0, y0=0.0):
		a = math.radians(ang)
		c = math.cos(a)
		s = math.sin(a)
		if ang in (0.0,90.0,180.0,270.0,-90.0,-180.0,-270.0):
			c = round(c)	# round numbers to avoid nasty extra digits
			s = round(s)
		return self.process(items, self.rotateFunc, Tab.transform, c, s, x0, y0)

	#----------------------------------------------------------------------
	# Use the orientation information to orient selected code
	#----------------------------------------------------------------------
	def orientLines(self, items):
		if not self.orient.valid: return "ERROR: Orientation information is not valid"
		c = math.cos(self.orient.phi)
		s = math.sin(self.orient.phi)
		return self.process(items, self.transformFunc, Tab.transform, c, s,
					self.orient.xo, self.orient.yo)

	#----------------------------------------------------------------------
	# Mirror Horizontal
	#----------------------------------------------------------------------
	def mirrorHFunc(self, new, old, *kw):
		changed = False
		for axis in 'XI':
			if axis in new:
				new[axis] = -new[axis]
				changed = True
		g = int(getValue('G',new,old))
		if g==2:
			new['G'] = 3
		elif g==3:
			new['G'] = 2
		return changed

	#----------------------------------------------------------------------
	# Mirror Vertical
	#----------------------------------------------------------------------
	def mirrorVFunc(self, new, old, *kw):
		changed = False
		for axis in 'YJ':
			if axis in new:
				new[axis] = -new[axis]
				changed = True
		g = int(getValue('G',new,old))
		if g==2:
			new['G'] = 3
		elif g==3:
			new['G'] = 2
		return changed

	#----------------------------------------------------------------------
	# Mirror horizontally/vertically
	#----------------------------------------------------------------------
	def mirrorHLines(self, items):
		return self.process(items, self.mirrorHFunc, None)

	#----------------------------------------------------------------------
	def mirrorVLines(self, items):
		return self.process(items, self.mirrorVFunc, None)

	#----------------------------------------------------------------------
	# Round all digits with accuracy
	#----------------------------------------------------------------------
	def roundFunc(self, new, old):
		for name,value in new.items():
			new[name] = round(value,CNC.digits)
		return bool(new)

	#----------------------------------------------------------------------
	# Round line by the amount of digits
	#----------------------------------------------------------------------
	def roundLines(self, items, acc=None):
		if acc is not None: CNC.digits = acc
		return self.process(items, self.roundFunc, None)

	#----------------------------------------------------------------------
	# Inkscape g-code tools on slice/slice it raises the tool to the
	# safe height then plunges again.
	# Comment out all these patterns
	#
	# FIXME needs re-working...
	#----------------------------------------------------------------------
	def inkscapeLines(self):
		undoinfo = []

		# Loop over all blocks
		self.initPath()
		newlines = []
		#last = None
		last = -1	# line location when it was last raised with dx=dy=0.0

		#for line in self.iterate():
		#for bid,block in enumerate(self.blocks):
		#	for li,line in enumerate(block):
		for line in self.lines():
			# step id
			# 0 - normal cutting z<0
			# 1 - z>0 raised  with dx=dy=0.0
			# 2 - z<0 plunged with dx=dy=0.0
			cmd = CNC.parseLine(line)
			if cmd is None:
				newlines.append(line)
				continue
			self.cnc.motionStart(cmd)
			xyza = self.cnc.motionPath()
			if self.cnc.dx==0.0 and self.cnc.dy==0.0:
				if self.cnc.z>0.0 and self.cnc.dz>0.0:
					last = len(newlines)
					#last = bid, li

				#elif self.cnc.z<0.0 and self.cnc.dz<0.0 and last is not None:
				elif self.cnc.z<0.0 and self.cnc.dz<0.0 and last>=0:
					# comment out all lines from last
					#lb, ll = last
					#while bid!=lb or li!=ll:
					#	b = self.blocks[lb]
					#	line = b[ll]
					#	if line and line[0] not in ("(","%"):
					#		undoinfo.append(b.setLineUndo(ll,"(%s)"%(line)))
					#	ll += 1
					#	if ll>=len(b):
					#		lb += 1
					#		ll = 0
					# last = None
					for i in range(last,len(newlines)):
						s = newlines[i]
						if s and s[0] != '(':
							newlines[i] = "(%s)"%(s)
					last = -1
			else:
				#last = None
				last = -1
			newlines.append(line)
			self.cnc.motionEnd()

		self.addUndo(self.setLinesUndo(newlines))

	#----------------------------------------------------------------------
	# Remove the line number for lines
	#----------------------------------------------------------------------
	def removeNlines(self, items):
		pass

	#----------------------------------------------------------------------
	# Re-arrange using genetic algorithms a set of blocks to minimize
	# rapid movements.
	#----------------------------------------------------------------------
	def optimize(self, items):
		n = len(items)

		matrix = []
		for i in range(n):
			matrix.append([0.0] * n)

		# Find distances between blocks (end to start)
		for i in range(n):
			block = self.blocks[items[i]]
			x1 = block.ex
			y1 = block.ey
			for j in range(n):
				if i==j: continue
				block = self.blocks[items[j]]
				x2 = block.sx
				y2 = block.sy
				dx = x1-x2
				dy = y1-y2
				matrix[i][j] = sqrt(dx*dx + dy*dy)
		#from pprint import pprint
		#pprint(matrix)

		best = [0]
		unvisited = range(1,n)
		while unvisited:
			last = best[-1]
			row = matrix[last]
			# from all the unvisited places search the closest one
			mindist = 1e30
			for i,u in enumerate(unvisited):
				d = row[u]
				if d < mindist:
					mindist = d
					si = i
			best.append(unvisited.pop(si))
		#print "best=",best

		undoinfo = []
		for i in range(len(best)):
			b = best[i]
			if i==b: continue
			ptr = best.index(i)
			# swap i,b in items
			undoinfo.append(self.swapBlockUndo(items[i], items[b]))
			# swap i,ptr in best
			best[i], best[ptr] = best[ptr], best[i]
		self.addUndo(undoinfo, "Optimize")

	#----------------------------------------------------------------------
	# Use probe information to modify the g-code to autolevel
	#----------------------------------------------------------------------
	def compile(self, queue, stopFunc=None):
		#lines  = [self.cnc.startup]
		paths   = []

		def add(line, path):
			if line is not None:
				if isinstance(line,str) or isinstance(line,unicode):
					queue.put(line+"\n")
				else:
					queue.put(line)
			paths.append(path)
		autolevel = not self.probe.isEmpty()
		self.initPath()
		for line in CNC.compile(self.cnc.startup.splitlines()):
			add(line, None)

		every = 1
		for i,block in enumerate(self.blocks):
			if not block.enable: continue
			for j,line in enumerate(block):
				every -= 1
				if every<=0:
					if stopFunc is not None and stopFunc():
						return None
					every = 50

				newcmd = []
				cmds = CNC.compileLine(line)
				if cmds is None:
					continue
				elif isinstance(cmds,str) or isinstance(cmds,unicode):
					cmds = CNC.breakLine(cmds)
				else:
					# either CodeType or tuple, list[] append at it as is
					#lines.append(cmds)
					if isinstance(cmds,types.CodeType) or isinstance(cmds,int):
						add(cmds, None)
					else:
						add(cmds, (i,j))
					continue

				skip   = False
				expand = None
				self.cnc.motionStart(cmds)

				# FIXME append feed on cut commands. It will be obsolete in grbl v1.0
				if CNC.appendFeed and self.cnc.gcode in (1,2,3):
					# Check is not existing in cmds
					for c in cmds:
						if c[0] in ('f','F'):
							break
					else:
						cmds.append(self.fmt('F',self.cnc.feed/self.cnc.unit))

				if autolevel and self.cnc.gcode in (0,1,2,3) and self.cnc.mval==0:
					xyza = self.cnc.motionPath()
					if not xyza:
						# while auto-levelling, do not ignore non-movement
						# commands, just append the line as-is
						#lines.append(line)
						#paths.append(None)
						add(line, None)
					else:
						extra = ""
						for c in cmds:
							if c[0].upper() not in ('G','X','Y','Z','A','I','J','K','R'):
								extra += c
						x1,y1,z1,a1 = xyza[0]
						if self.cnc.gcode == 0:
							g = 0
						else:
							g = 1
						for x2,y2,z2,a2 in xyza[1:]:
							for x,y,z,a in self.probe.splitLine(x1,y1,z1,a1,x2,y2,z2,a2):
								add("G%d%s%s%s%s%s"%\
									(g,
									 self.fmt('X',x/self.cnc.unit),
									 self.fmt('Y',y/self.cnc.unit),
									 self.fmt('Z',z/self.cnc.unit),
									 self.fmt('A',z/self.cnc.unit),
									 extra),
								    (i,j))
								extra = ""
							x1,y1,z1,a1 = x2,y2,z2,a2
					self.cnc.motionEnd()
					continue
				else:
					# FIXME expansion policy here variable needed
					# Canned cycles
					if CNC.drillPolicy==1 and \
					   self.cnc.gcode in (81,82,83,85,86,89):
						expand = self.cnc.macroGroupG8X()
					# Tool change
					elif self.cnc.mval == 6:
						if CNC.toolPolicy == 0:
							pass	# send to grbl
						elif CNC.toolPolicy == 1:
							skip = True	# skip whole line
						elif CNC.toolPolicy >= 2:
							expand = CNC.compile(self.cnc.toolChange())
					self.cnc.motionEnd()

				if expand is not None:
					for line in expand:
						add(line, None)
					expand = None
					continue
				elif skip:
					skip = False
					continue

				for cmd in cmds:
					c = cmd[0]
					try: value = float(cmd[1:])
					except: value = 0.0
					if c.upper() in ("F","X","Y","Z","I","J","K","R","P"):
						cmd = self.fmt(c,value)
					else:
						opt = ERROR_HANDLING.get(cmd.upper(),0)
						if opt == SKIP: cmd = None
					if cmd is not None:
						newcmd.append(cmd)

				add("".join(newcmd), (i,j))

		return paths

#if __name__=="__main__":
#	orient = Orient()
#	orient.add(  0,  0, 100, 50)
#	orient.add( 50, 10, 150, 60)
#	orient.add(100, 20, 200, 70)
#	phi,xo,yo = orient.solve()
#	print phi,degrees(phi),xo,yo
#
#	orient.clear()
#	orient.add(  0,  0, -50, 100)
#	orient.add( 50, 10, -60, 150)
#	orient.add(100, 20, -70, 200)
#	phi,xo,yo = orient.solve()
#	print phi,degrees(phi),xo,yo
#
#	import pdb; pdb.set_trace()
#	#print Block.operationName("door","in")
#	print Block.operationName("door [in:2,cut:0.1]","cut:0.5")
#	print Block.operationName("door [in:2,cut:0.1]","in")