#!/usr/bin/env python

from __future__ import division
import numpy as np
from scipy import interpolate
import matplotlib.pyplot as plt


def noise(nnodes, amplitude):
    x = np.linspace(0, 1, nnodes)
    y = x
    z = amplitude * np.random.uniform(-1, +1, (nnodes, nnodes))
    return interpolate.RectBivariateSpline(x, y, z)


class Noise(object):
    def __init__(self, size, details=1):
        self._f = [noise(2**(size+n), 1/2**n) for n in range(details)]

    def __call__(self, x, y):
        return sum([f(x, y, grid=True) for f in self._f])


f = Noise(3, 6)
x = np.linspace(0, 1, 1024)
y = x

with plt.style.context('ggplot'):
    plt.imshow(f(x, y))
    plt.savefig('src03.png')