code: def coord_to_pixel(self, lat, lon, width, ground_width, lat2, lon2):
  		'''return pixel coordinate (px,py) for position (lat2,lon2)
  		in an area image. Note that the results are relative to top,left
  		and may be outside the image'''
  		pixel_width = ground_width / float(width)
  
  		if lat is None or lon is None or lat2 is None or lon2 is None:
  			return (0,0)
  
  		dx = mp_util.gps_distance(lat, lon, lat, lon2)
  		if lon2 < lon:
  			dx = -dx
  		dy = mp_util.gps_distance(lat, lon, lat2, lon)
  		if lat2 > lat:
  			dy = -dy
  
  		dx /= pixel_width
  		dy /= pixel_width
  		return (int(dx), int(dy)f coord_to_pixel(self, lat, lon, width, ground_width, lat2, lon2):
  		'''return pixel coordinate (px,py) for position (lat2,lon2)
  		in an area image. Note that the results are relative to top,left
  		and may be outside the image'''
  		pixel_width = ground_width / float(width)
  
  		if lat is None or lon is None or lat2 is None or lon2 is None:
  			return (0,0)
  
  		dx = mp_util.gps_distance(lat, lon, lat, lon2)
  		if lon2 < lon:
  			dx = -dx
  		dy = mp_util.gps_distance(lat, lon, lat2, lon)
  		if lat2 > lat:
  			dy = -dy
  
  		dx /= pixel_width
  		dy /= pixel_width
  		return (int(dx), int(dy))
docs: return pixel coordinate (px,py) for position (lat2,lon2)
  		in an area image. Note that the results are relative to top,left
  		and may be outside the image