Show plasma animation on Raspberry Pi Sense HAT LED

plasma_hat.py

#!/usr/bin/python

import evdev
from sense_hat import SenseHat
from math import *
from time import sleep
import colorsys
import numpy
from datetime import datetime, timedelta

"""
Before running execute the following to make sure all libraries are installed :

sudo apt-get install python-dev python-pip python-sense-hat
sudo pip install evdev
sudo pip install numpy

KEY_LEFT	Faster
KEY_RIGHT	Slower
"""

"""
 * 'Plasma' demo effect
 *
 * Cycles of changing colours warped to give an illusion of liquid, organic movement.
 * Colors are the sum of sine functions and various formulas.  
 * Based on formula by Robert Klep.
 *
 * http://luis.net/projects/processing/plasma/
 * 
 """

active_page = 1
frameCount = 0
width = 8
height = 8
pixelSize=360.0/(width*height)
fps=10
pixel_array = numpy.zeros((2,width*height,3),numpy.uint8)
sense = SenseHat ()

def setup():
	global frameCount
	frameCount = 24

def update():
	global frameCount
	global pixelSize
	global width
	global height
	global active_page
	active_page ^= 1

	frameCount += 1

	if frameCount >= 359:
		frameCount = 1

	# enable this to control the speed of animation regardless of CPU power
	# int timeDisplacement = millis()/30;

	# this runs plasma as fast as your computer can handle
	timeDisplacement = frameCount;

	# no need to do this math for every pixel
	calculation1 = sin(radians(timeDisplacement * 0.61655617));
	calculation2 = sin(radians(timeDisplacement * -3.6352262));
	calculation3 = sin(radians(timeDisplacement * 1.6352262));

	# plasma algorithm
	for x in range(width):
		s1 = 128.0 + (128.0 * sin(radians((x * 45)) * calculation1));

		for y in range(height):
			s2 = 128.0 + (128.0 * sin(radians(y * 45) * calculation2));
			s3 = 128.0 + (128.0 * sin(radians(((x * 45) + (y * 45) + timeDisplacement * calculation3 * 5) / 2)));
			s = (s1 + s2 + s3) / 3.0;
			rgb = colorsys.hls_to_rgb(int(s) / 255.0, int(255 - s / 2.0) / 255.0, int(calculation3 * 255) / 255.0);
			# sense.set_pixel(x, y, int(rgb[0] * 255.0), int(rgb[1] * 255.0), int(rgb[2] * 255.0));
			r = int(abs(rgb[0] * 255.0))
			g = int(abs(rgb[1] * 255.0))
			b = int(abs(rgb[2] * 255.0))
			#print (r,g,b)
			pixel_array[active_page][(y * height) + x] = [r,g,b]
			#print ((y * height) + x, pixel_array[active_page][(y * height) + x])
		# sleep (0.1);

# main loop
def draw():
	sense.set_pixels (pixel_array[active_page ^ 1])

def main():
	setup ()
	draw_period = timedelta(milliseconds=1000/fps)
	next_draw_time = datetime.now() + draw_period
	while True:
		try:
			#print ("Update")
			update()
			if datetime.now() > next_draw_time:
				#print("Draw")
				draw()
				next_draw_time += draw_period
		except KeyboardInterrupt:
			sense.clear()
			exit(0)

main()