Coolfractal on a nokia 5110 GLCD

coolfractal.ino

/*********************************************************************
This is an example sketch for our Monochrome Nokia 5110 LCD Displays

  Pick one up today in the adafruit shop!
  ------> http://www.adafruit.com/products/338

These displays use SPI to communicate, 4 or 5 pins are required to
interface

Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!

Written by Limor Fried/Ladyada  for Adafruit Industries.
BSD license, check license.txt for more information
All text above, and the splash screen must be included in any redistribution
*********************************************************************/

#include <Adafruit_GFX.h>
#include <Adafruit_PCD8544.h>

#define SIZECON 2.4

#define PIN_SCE   8
#define PIN_RESET 4
#define PIN_DC    5
#define PIN_SDIN  6
#define PIN_SCLK  7

Adafruit_PCD8544 display = Adafruit_PCD8544(PIN_SCLK,PIN_SDIN,PIN_DC,PIN_SCE,PIN_RESET);

void setup()   {


  display.begin();
  // init done

  // you can change the contrast around to adapt the display
  // for the best viewing!
  display.setContrast(54);

  randomSeed(analogRead(0));
  delay(analogRead(3));
  randomSeed(random(random(analogRead(0) + analogRead(1))));

  display.display(); // show splashscreen
  delay(1000);
  display.clearDisplay();   // clears the screen and buffer

}

void loop() {
  float a = random(1000.0) / 1000.0;
  float b = 0.9998;
  float c = 2.0 - 2.0 * a;
  float j = 0.0;
  float x = 0.0;
  float y = (random(1000.0)/1000.0) * 12.0 + 0.1;
  float z = 0.0;
  float xp = 0.0;
  float yp = 0.0;
  
  for (int i = 0; i < 700; i++) {
    z = x;
    x = b * y + j;
    j = a * x + c * pow(x,2) / (1 + pow(x,2));
    y = j - z;
    xp = (x * SIZECON) + 42;
    yp = (y * SIZECON) + 24;
    
    display.drawPixel(xp, yp, BLACK);
    display.display();
  }

}