old_contents: size(100, 100)
  noStroke()
  
  fill('#0000FF')
  rect(10, 10, 10, 10)
  assert get(15, 15) == 0xFF0000FF
  
  square(10, 30, 10)
  assert get(15, 35) == 0xFF0000FF
  
  fill(255)
  rect(20, 10, 10, 10)
  assert get(25, 15) == 0xFFFFFFFF
  
  fill(0xFF00FF00)
  rect(30, 10, 10, 10)
  assert get(35, 15) == 0xFF00FF00
  
  fill(lerpColor(0, 255, .5))
  rect(40, 10, 10, 10)
  assert get(45, 15) == 0xFF808080
  
  fill(lerpColor('#0000FF', '#FF0000', .5))
  rect(50, 10, 10, 10)
  assert get(55, 15) == 0xFF800080
  
  # Fill a pink square the hard way.
  loadPixels()
  assert pixels[15 * width + 15] == 0xFF0000FF
  for x in range(60, 70):
      for y in range(10, 20):
          pixels[y * width + x] = 0xFFDD00DD
  updatePixels()
  assert get(65, 15) == 0xFFDD00DD
  
  # Fill a yellow square the almost as hard way.
  for x in range(70, 80):
      for y in range(10, 20):
          set(x, y, '#EEEE00')
  assert get(75, 15) == 0xFFEEEE00
  
  print 'OK'
  exit()
  
new_contents: size(100, 100)
  noStroke()
  
  fill('#0000FF')
  rect(10, 10, 10, 10)
  assert get(15, 15) == 0xFF0000FF
  
  square(10, 30, 10)
  assert get(15, 35) == 0xFF0000FF
  
  circle(100, 100, 10)
  assert get(99, 99) == 0xFF0000FF
  
  fill(255)
  rect(20, 10, 10, 10)
  assert get(25, 15) == 0xFFFFFFFF
  
  fill(0xFF00FF00)
  rect(30, 10, 10, 10)
  assert get(35, 15) == 0xFF00FF00
  
  fill(lerpColor(0, 255, .5))
  rect(40, 10, 10, 10)
  assert get(45, 15) == 0xFF808080
  
  fill(lerpColor('#0000FF', '#FF0000', .5))
  rect(50, 10, 10, 10)
  assert get(55, 15) == 0xFF800080
  
  # Fill a pink square the hard way.
  loadPixels()
  assert pixels[15 * width + 15] == 0xFF0000FF
  for x in range(60, 70):
      for y in range(10, 20):
          pixels[y * width + x] = 0xFFDD00DD
  updatePixels()
  assert get(65, 15) == 0xFFDD00DD
  
  # Fill a yellow square the almost as hard way.
  for x in range(70, 80):
      for y in range(10, 20):
          set(x, y, '#EEEE00')
  assert get(75, 15) == 0xFFEEEE00
  
  print 'OK'
  exit()
  
subject: Add test for circle method