Select Page

# Mandelbrot Set on Adafruit CLUE

by | Jul 2, 2020

The Mandelbrot set is an implentation of fractal theory that makes an ideal test for coding on any device.

## Mandelbrot Set for Adafruit Clue (MicroPython)

``````# Manage Capacitor Voltage using micro:bit
# Copyright R J Zealley 10/07/2020
# Licence: copy and resuse with attribution

import board
import displayio

MAX_ITER = 24
WIDTH = 240
HEIGHT = 240

# Plot window
RE_START = -2
RE_END = 1
IM_START = -1
IM_END = 1

def mandelbrot(c):
z = 0
n = 0
while abs(z) <= 2 and n < MAX_ITER:
z = z*z + c
n += 1
return n

def show_values():
for a in range(-10, 10, 5):
for b in range(-10, 10, 5):
c = complex(a / 10, b / 10)
print(c, mandelbrot(c))

def clear_screen():
# Make a background color fill
color_bitmap = displayio.Bitmap(320, 240, 1)
color_palette = displayio.Palette(1)
color_palette[0] = 0xFFFFFF
bg_sprite = displayio.TileGrid(color_bitmap, x=0, y=0, pixel_shader=color_palette)
splash.append(bg_sprite)

def draw_mandelbrot():
color_bitmap = displayio.Bitmap(WIDTH, HEIGHT, 16)
color_palette = displayio.Palette(16)

color_palette[0] = 0x000000
color_palette[1] = 0x000080
color_palette[2] = 0x008000
color_palette[3] = 0x008080
color_palette[4] = 0x800000
color_palette[5] = 0x800080
color_palette[6] = 0x808000
color_palette[7] = 0xC0C0C0
color_palette[8] = 0x808080
color_palette[9] = 0x0000FF
color_palette[10] = 0x00FF00
color_palette[11] = 0x00FFFF
color_palette[12] = 0xFF0000
color_palette[13] = 0xFF00FF
color_palette[14] = 0xFFFF00
color_palette[15] = 0xFFFFFF

for x in range(0, WIDTH):
for y in range(0, HEIGHT):
# Convert pixel coordinate to complex number
c = complex(RE_START + (x / WIDTH) * (RE_END - RE_START),
IM_START + (y / HEIGHT) * (IM_END - IM_START))
# Compute the number of iterations
m = mandelbrot(c)
# The color depends on the number of iterations
color = 15 - int(m * 15 / MAX_ITER)

# Plot the point
#splash.append(Line(x, y, x, y, color))
#splash.append(Circle(x, y, 1, outline=color))
#draw.point([x, y], (color, color, color))
color_bitmap[x,y] = color

bg_sprite = displayio.TileGrid(color_bitmap, x=0, y=0, pixel_shader=color_palette)
splash.append(bg_sprite)

def calc_mandelbrot():
for x in range(0, WIDTH):
for y in range(0, HEIGHT):
# Convert pixel coordinate to complex number
c = complex(RE_START + (x / WIDTH) * (RE_END - RE_START),
IM_START + (y / HEIGHT) * (IM_END - IM_START))
# Compute the number of iterations
m = mandelbrot(c)
# The color depends on the number of iterations
color = 15 - int(m * 15 / MAX_ITER)
# Plot the point
print(str(x), str(y), str(color))

if __name__ == "__main__":
print("Mandelbrot:")

while True:
if clue.button_a:
splash = displayio.Group(max_size=4)
board.DISPLAY.show(splash)

clear_screen()

draw_mandelbrot()

if clue.button_b:
calc_mandelbrot()``````