Mandelbrot Fractal

import pygame

pygame.init()

screen_dimensions = (1920, 1080)
window = pygame.display.set_mode(screen_dimensions)

pixel_array = pygame.PixelArray(window)

for x in range(len(pixel_array)):
    for y in range(len(pixel_array[0])):
        dx = (x-1000)/600
        dy = (y-540)/600
        a = dx
        b = dy

        for t in range(200):
            d = (a*a)-(b*b)+dx
            b = 2*(a*b)+dy
            a = d
            H = d>200

            if H:
                pixel_array[x, y] = (abs(t-20), abs(t-50), abs(t-65))
                break

pixel_array.close()

run = True
while run:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

    pygame.display.flip()