# Cutting mat registration image

canvas = document.createElement 'canvas'
context = canvas.getContext '2d'
document.body.appendChild canvas

scale = 72
scaleHalf = scale/2
width = 35*scale
canvas.width = width+5
height = 23*scale
canvas.height = height+5
# Offset for whole pixels
context.translate 3+0.5, 3+0.5

bg = 'transparent'
context.fillStyle = bg
context.fillRect 0, 0, width, height

segment = (x1, y1, x2, y2) ->
  context.beginPath()
  context.moveTo x1, y1
  context.lineTo x2, y2
  context.stroke()

draw = ->
  x = 0
  while x <= width
    segment x, 0, x, height
    x += scale

  y = 0
  while y <= height
    segment 0, y, width, y
    y += scale


  # Subgrid
  x = scale+scaleHalf
  while x < width-scale
    segment x, scale, x, height-scale
    x += scale

  y = scale+scaleHalf
  while y < height-scale
    segment scale, y, width-scale, y
    y += scale


  # Diagonal lines
  #45
  segment 0, height, height, 0
  #90
  segment height/2, height/2, height, height
  #60
  segment 0, height, height*Math.tan(Math.PI*1/6), 0
  #30
  segment 0, height, height*Math.tan(Math.PI*1/3), 0


  # Eighth inch marks
  x = 0
  while x <= width
    segment x, 0, x, scale/8
    segment x, height, x, height-scale/8
    x += scale/8

  y = 0
  while y <= height
    segment 0, y, scale/8, y
    segment width, y, width-scale/8, y
    y += scale/8


context.strokeStyle = 'black'
context.lineWidth = 3
draw()
context.strokeStyle = 'white'
context.lineWidth = 1
draw()