pattern.py

import matplotlib.pyplot as plt
import random, math

sizex = 10
sizey = 30
verticalweight = 4
maxlenght = 8

random.seed()

xunit = math.sqrt(3)
lines = []
listofPoints = []
points = {}
grid = []

def drawPoint(p,c,size=1):
    x,y = c
    p.scatter(x * xunit, y*2 if x%2 else 1+y*2, c='k', s=size)

def drawLines(p):
    for l in lines:
        if len(l) == 1:
            drawPoint(p, l[0])
        else:
            tmp = []
            for t in l:
                x,y = t
                tmp.append([x * xunit, y*2 if x%2 else 1+y*2])
            xs, ys = zip(*tmp)
            ls = p.plot(xs, ys)
            p.setp(ls, linewidth=1, color='k')

def getAdjPoints(c):
    x,y = c
    tmplist = [[x+1,y], [x-1,y]]
    for _ in range(verticalweight):
        tmplist.append([x,y-1])
        tmplist.append([x,y+1])
    if x%2:
        tmplist.append([x+1,y-1])
        tmplist.append([x-1,y-1])
    else:
        tmplist.append([x-1,y+1])
        tmplist.append([x+1,y+1])
    retlist = []
    for tmp in tmplist:
        if tmp in listofPoints:
            retlist.append(tmp)
    return retlist

# Grid generation
for x in range(sizex):
    tmp = []
    for y in range(sizey):
        p=[x,y]
        tmp.append(p)
        listofPoints.append(p)
    grid.append(tmp)

# Lines generation
while (len(listofPoints)):
    line = []
    linelen = random.randrange(maxlenght-2,maxlenght)
    c = listofPoints.pop(random.randrange(len(listofPoints)))
    line.append(c)
    for i in range(linelen - 1):
        nextc = getAdjPoints(c)
        if len(nextc):
            c = nextc[random.randrange(len(nextc))]
            listofPoints.remove(c)
            line.append(c)
        else:
            break
    lines.append(line)

# Pattern drawing
drawLines(plt)
x = plt.gca()
x.axes.xaxis.set_visible(False)
x.axes.yaxis.set_visible(False)
x.figure.set_size_inches(sizex/5,sizey/5)
# plt.savefig("pattern.svg", format="svg")
plt.show()