def tkCartesian( x, y, direction, distance ):
      '''Complementary to tkPolar().  Given a x,y point, direction in
      radians (0 is at 3 o'clock, 1/2 PI is straight down, etc.) and a
      distance (all as python float or int).  This function returns
      the x and y of the end-point.'''
      import math
      deltaX = distance * math.cos( direction )
      deltaY = distance * math.sin( direction )
      
      return x + deltaX, y + deltaY
Complementary to tkPolar().  Given a x,y point, direction in
      radians (0 is at 3 o'clock, 1/2 PI is straight down, etc.) and a
      distance (all as python float or int).  This function returns
      the x and y of the end-point.
recipes/Python/552745_tkMath_convert_between_pixels_inches_cm/recipe-552745.py