Aliased Circles

Inspired by this I wrote a little script to create antialiased circles in python
The Gist:

	#! /usr/bin/env python
	# -*- coding: latin-1 -*-
	import math
	characters = [32,0x2591,0x2592,0x2593,0x2588]
	breakpoints = [0.1,0.177,0.316,0.563]
	#reakpoints = [0.2,0.4,0.6,0.8]
	def raster(x,y,R,center,SIGMA=1.5):
	r = math.sqrt(math.pow(x-center,2)+math.pow( (y-center)*0.9,2))
	return math.exp(-math.pow(r-R,2)/SIGMA)
	from bisect import bisect
	def genchr(z):
	n = bisect(breakpoints,z)
	return unichr(characters[n])
	def circle(R,sigma=1.5,side=10):
	size = 2*R + 2*side
	array = []
	for z in xrange(size):
	array.append([' ']*size)
	center = side+R
	for i in xrange(size):
	for j in xrange(size):
	z = raster(i,j,R,center,sigma)
	foo = genchr(z)
	array[i][j] = foo
	#print "{},{}:{}:{}".format(i,j,z,foo)
	array[center][center] = 'X'
	return array
	import sys
	def printarr(arr):
	for line in arr:
	for c in line:
	print c,
	print
	if __name__=="__main__":
	if len(sys.argv)>1:
	if len(sys.argv)==2:
	printarr(circle(int(sys.argv[1])))
	elif len(sys.argv)==3:
	printarr(circle(int(sys.argv[1]),float(sys.argv[2])))
	else:
	printarr(circle(int(sys.argv[1]),float(sys.argv[2]),int(sys.argv[3])))
	else:
	mesg = r"""Usage: circle R [SIGMA] [SIDE] where R is radius, sigma is sigma and side is buffer on edges"""
	print mesg

view raw circle.py hosted with ❤ by GitHub

Example output:

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view raw circle15.txt hosted with ❤ by GitHub