bresenham.py

#!/usr/bin/python
# -*- coding: utf-8 -*-

matrix = [[None for j in xrange(10)] for i in xrange(10)]

def print_matrix():
    for line in matrix:
        for col in line:
            print str(col)+'\t',
        print ''

def plot(x, y, D):
    print 'pinta ({}, {}). D = {}'.format(x, y, D)
    matrix[x][y] = 'X'

def bresenham(x0, y0, x1, y1):
    dx = x1 - x0
    dy = y1 - y0
    D = dy - dx
    y = y0

    for x in range(x0, x1):
        plot(x,y,D)
        if D >= 0:
            '''
            Se a reta cresce mais em Y que em X, ele retira a variação em X?
            '''
            y += 1
            D -= dx
        D += dy

if __name__ == '__main__':
    bresenham(0, 1, 6, 4)
    print ''
    print print_matrix()