# Tk_3D_sphere.py

# Tk_3D_sphere.py

from Tkinter import *
from PIL import Image, ImageTk
import random
import math
import time
ww = 600
hh = 600

shades = range(255,1,-1)

def normalize(v):
    len = math.sqrt(v[0]**2 + v[1]**2 + v[2]**2)
    return (v[0]/len, v[1]/len, v[2]/len)

def dot(x,y):
    d = x[0]*y[0] + x[1]*y[1] + x[2]*y[2]
    return -d if d < 0 else 0

def draw_sphere(r, k, ambient, light):
    pixels = [(128,128,128)]*(ww*hh)
    for i in range(int(math.floor(-r)),int(math.ceil(r)+1)):
        x = i + 0.5
        for j in range(int(math.floor(-2*r)),int(math.ceil(2*r)+1)):
            y = j/2 + 0.5
            if x*x + y*y <= r*r:
                vec = normalize((x,y,math.sqrt(r*r - x*x - y*y)))
                b = dot(light,vec)**k + ambient
                intensity = int((1-b)*(len(shades)-1))
                c = shades[intensity] if 0 <= intensity < len(shades) else shades[0]
                pixels[int(x+((y-(hh/2))*ww))] = (0,c,0)
    return pixels



root = Tk()
root.title("Tk 3D Sphere")
root.geometry("%dx%d+-10+0"%(ww,hh))
canvas = Canvas(root, width=ww, height=hh)
canvas.pack()

pixels = [(0,128,0)]*(ww*hh)

light = normalize((30,30,-50))
pixels = draw_sphere(ww/2-20,4,0.1, light)

img = Image.new("RGB", (ww, hh))
img.putdata(pixels)

imgTk = ImageTk.PhotoImage(img)
canvas.create_image(0, 0, anchor=NW, image=imgTk)
canvas.update()