# sinusoids are used to rotate the checker scene

import math

def rotateX(x, y, angle):
  return (x*math.cos(angle)-y*math.sin(angle))

def rotateY(x, y, angle):
  return (y*math.cos(angle)+x*math.sin(angle))

def checkColor(x, y):
  x = int(x)
  y = int(y)
  color = 0
  bx = 0
  by = 0
  if y <> 50:
    bx = (x-50)*2/(50-y)
    by = (y*2)/(50-y)
  color = (int(bx+by)%2)*100
  color = 100-((100-color) * abs(y-50)/100)
  return int(color)

def drawChecks(angle):
  for y in range(0, 101):
    for x in range(0, 101):
      g.setPixel(x,y,checkColor(50+round(rotateX(x-50,y-50,angle)),-10+round(rotateY(x-50,y-50,angle))))

drawChecks(math.pi/8)