Generate Post-It banners for plotting with your MakerBot Unicorn

sticky_notes.py

#! /usr/bin/env python

# Usage: python sticky_notes.py 'Your Message Here!' > out.gcode

import cairo
import sys
import re

### BEGIN CONFIGURATION ###
feedrate = 3500
start_delay = 120
stop_delay = 120
pen_up_angle = 50
pen_down_angle = 30
tool_up_height = 15
size = 20
font_face = "Georgia"
### END   CONFIGURATION ###

preamble = [
            "G21 (metric ftw)", 
            "G90 (absolute mode)"
           ]

sheet_header = [
                "G92 X0 Y0 Z0 (zero all axes",
                "M300 S%d (pen down)" % (pen_down_angle),
                "G4 P%d (wait %dms" % (start_delay, start_delay),
                "M300 S%d (pen up)" % (pen_up_angle),
                "G4 P%d (wait %dms" % (stop_delay, stop_delay),
                "M18 (disengage drives)",
                "M01 (Was registration test successful?)",
                "M17 (engage drives if YES, and continue)",
                "(end of sheet header)"
               ]

sheet_footer = [
                "(Start of sheet footer.)",
                "M300 S%d (pen up)" % (pen_up_angle),
                "G4 P%d (wait %dms" % (stop_delay, stop_delay),
                "G0 X0 Y0 Z%d F%d (retrieving platform)" % (tool_up_height, feedrate),
                "G4 P300 (wait 300ms)",
                "M01 (Have you retrieved the print?)",
                "(machine halts until 'okay')",
                "G4 P%d (wait %dms" % (start_delay, start_delay),
                "G0 Z0 F%d (return to start position of current sheet)" % (feedrate),
                "G4 P300 (wait 300ms)",
                "M18 (disengage drives)",
                "(End of sheet footer)",
               ]
postscript = ["(End of print job)", 
              "M300 S%d (pen up)" % (pen_up_angle),
              "M18 (disengage drives)"
             ]
          

def draw_character(char, cr):
    x_bearing, y_bearing, width, height = cr.text_extents(char)[:4]
    xoff = width/2.0
    yoff = height/2.0
    cr.text_path(char)
    path = cr.copy_path_flat()
    print "M300 S%d (pen up)"  % (pen_up_angle)
    print "G4 P%d (wait %dms)" % (stop_delay, stop_delay)
    pen_down = 0
    shape_start = [0,0]  # first point
    next_shape = 1
    for line in path:
      if(line[0] == cairo.PATH_MOVE_TO):
        if(next_shape == 1):
          shape_start = line[1]
          next_shape = 0
        if(pen_down == 1):
          print "M300 S%d (pen up)" % (pen_up_angle)
          print "G4 P%d (wait %dms)" % (stop_delay, stop_delay)
          pen_down = 0
        print "G1 X%f Y%f F%f" % (line[1][0]-xoff, line[1][1]*-1.0-yoff, feedrate)
      if(line[0] == cairo.PATH_LINE_TO):
        if(next_shape == 1):
          shape_start = line[1]
          next_shape = 0
        if(pen_down == 0):
          print "M300 S%d (pen down)" % (pen_down_angle)
          print "G4 P%d (wait %dms)" % (start_delay, start_delay)
          pen_down = 1
        print "G1 X%f Y%f F%f" % (line[1][0]-xoff, line[1][1]*-1.0-yoff, feedrate)
      if(line[0] == cairo.PATH_CLOSE_PATH):
        print "G1 X%f Y%f F%f" % (shape_start[0]-xoff, shape_start[1]*-1.0-yoff, feedrate)
        next_shape = 1
        if(pen_down == 1):
          print "M300 S%d (pen up)" % (pen_up_angle)
          print "G4 P%d (wait %dms)" % (stop_delay, stop_delay)
          pen_down = 0

def create_context():
    surface = cairo.SVGSurface("foo.svg", size, size)
    cr = cairo.Context(surface)
    cr.scale(size, size)
    cr.set_line_width(0.01)
    cr.select_font_face(font_face, 
                        cairo.FONT_SLANT_NORMAL,
                        cairo.FONT_WEIGHT_BOLD)
    cr.set_font_size(64)
    return cr

def sanitize_message(message):
    return re.sub(r'[ 	]','', message)

if __name__ == '__main__':
    if(len(sys.argv) != 2):
        message = "Hello"
    else:
        message = sys.argv[1]
    message = sanitize_message(message)
    print "(Sticky Notes banner for '%s')" % (message)
    print "\n".join(preamble)  # print preamble codes
    for char in str(message):
        print "\n".join(sheet_header) # print sheet header
        cr = create_context()
        draw_character(char, cr)
        print "\n".join(sheet_footer) # print sheet header
    print "\n".join(postscript) # print postscript codes