Graphic 3

graphic3.py

import os
import numpy as np
from PIL import Image

#-------------------------------------------------------------------
#
#  helper functions
#
def create_complex_plane(X, Y, x0, x1, y0, y1, endpoint=False):
    I = np.indices((Y,X)).astype(np.float64)
    fy = (y1 - y0) / (Y - 1) if endpoint else (y1 - y0) / Y
    fx = (x1 - x0) / (X - 1) if endpoint else (x1 - x0) / X
    return (x0 + fx*I[1]) + 1j*(y0 + fy*I[0])
    
def colorize(R, bins, rgb0, rgb1 = None):    
    bin_widths = bins[1:] - bins[:-1]
    D = np.digitize(R, bins) - 1
    C0 = np.take(rgb0, D, axis=0)
    if rgb1 is None:
        return C0
    # create gradients between rgb0 and rgb1
    C1 = np.take(rgb1, D, axis=0)
    F = (R - np.take(bins, D))/np.take(bin_widths, D)
    F = np.repeat(F, 3)
    F.shape = C0.shape
    C = (1-F)*C0 + F*C1
    return C

def normalize(x, floor = -1e+300, ceil = +1e+300, nan_replace = 0.0):
    x = np.where(np.isnan(x), nan_replace, x)
    x = np.maximum(x, floor)
    x = np.minimum(x, ceil)
    xmin, xmax = np.min(x), np.max(x)
    print(xmin, xmax)
    return (x - xmin) / (xmax - xmin)

def save_rgb(R, path):
    R = np.round(R).astype(np.uint8)
    image = Image.fromarray(R, mode='RGB')
    image.save(path, quality=85)        

#-------------------------------------------------------------------

def mod1s(a, b):
    return np.mod(a, 1 + np.floor(np.abs(b)))

W, H = 800, 800
s = 80
b0_3 = create_complex_plane(W, H, -s, s, -s, s)
b0_4 = np.log(b0_3) - np.sqrt(b0_3)
x1 = np.abs(b0_4)
b0_6 = np.real(b0_4)
b7 = np.sqrt(x1) + np.cos(b0_6)
b0_5 = np.imag(b0_4)
x3 = np.conj(b0_4)
b8 = mod1s(np.abs(b0_5),x3*b0_6)
x0 = np.cos(b7-b8)-(2*b7-2*b8-b7*b8)
x9 = 56.763*(np.sin(b8)-(b7-0.111))
r = np.cos(x0+0.1295)-np.cos(np.pi/2-x9)

#-------------------------------------------------------------------
color_stops  = np.array([-0.0001, 0.1516, 0.4102, 0.7137, 0.8215, 1.0268])
rgb_from = [(239, 239, 239), (120, 120, 120), (20, 20, 20), (20, 20, 20), (31, 31, 31), (101, 101, 101)]
rgb_to = rgb_from[1:]

r = normalize(r)
r = colorize(r, color_stops, rgb_from, rgb_to)
#-------------------------------------------------------------------
save_rgb(r, 'out.jpg')

out.jpg