Processing Snowflake

// Snowflakes: http://solemone.de/demos/snow-effect-processing/
// Hue slider: http://cs1335-documentation.readthedocs.io/en/latest/hsbSlider.html

void setup() {
  size(1000, 600, P3D);
  smooth();
  surface.setResizable(true);
  colorMode(HSB);
  stroke(0,0,0);


  // Snowflakes setup
  for(int i = 0; i < quantity; i++) {
    flakeSize1[i] = round(random(minFlakeSize, maxFlakeSize));
    xPosition[i] = random(0, width);
    yPosition[i] = random(0, height);
    direction[i] = round(random(0, 1));
  }

}

int z = 0;
// Snowflake variables
int quantity = 300;
float [] xPosition = new float[quantity];
float [] yPosition = new float[quantity];
int [] flakeSize1 = new int[quantity];
int [] direction = new int[quantity];
int minFlakeSize = 1;
int maxFlakeSize = 5;


// Snowflake variables
float flakeSize = 30;
float difference = 50;
float layerTwo = 50;
float layerThree = layerTwo + difference;
float layerFour = layerTwo + (difference * 2);

// Slider variables
float marginLeft = 20;
float handle1 = marginLeft;
float handle2 = marginLeft;
float handle3 = marginLeft;
float barWidth = 255;
float barHeight = 6;
float handleSize = 20;


// Hue bar variables
float _barWidth = 255.0; //slider-bar width;
float _hueVal = _barWidth/2; //initial hueValue global value


void draw() {
  z++;
  background(0);

  for(int i = 0; i < xPosition.length; i++) {
    fill(random(0, 255), random(0, 255), random(0, 255));

    ellipse(xPosition[i], yPosition[i], flakeSize1[i], flakeSize1[i]);

    if(direction[i] == 0) {
      xPosition[i] += map(flakeSize1[i], minFlakeSize, maxFlakeSize, .1, .5);
    } else {
      xPosition[i] -= map(flakeSize1[i], minFlakeSize, maxFlakeSize, .1, .5);
    }

    yPosition[i] += flakeSize1[i] + direction[i];

    if(xPosition[i] > width + flakeSize1[i] || xPosition[i] < -flakeSize1[i] || yPosition[i] > height + flakeSize1[i]) {
      xPosition[i] = random(0, width);
      yPosition[i] = -flakeSize1[i];
    }

  }


  fill(255);
  stroke(4);
  rectMode(CORNER);

  // Scrollbars
  rect(marginLeft, 20, barWidth, barHeight);
  translate(0, 0, 2);
  ellipse(handle1, 25, handleSize, handleSize);

  rect(marginLeft, 60, barWidth, barHeight);
  translate(0, 0, 2);
  ellipse(handle2, 65, handleSize, handleSize);

  // Hue bar
  _hueVal= drawSlider(marginLeft, 100.0,_barWidth,barHeight,_hueVal);


  // Snowflake
  translate(width / 2, height / 2, -1);
  rotate(radians(width - mouseX) * 0.5);

  // Middle
  rectMode(CENTER);
  stroke(0, 100);
  fill(_hueVal,255,255);  //use the new _hueValue to set fill for drawing canvas object
  ellipse(0, 0, flakeSize, flakeSize);

  // Spokes
  for (int i = 0; i < 8; i++) {
    rotate(radians(45));
    ellipse(layerTwo, layerTwo, flakeSize, flakeSize);
    rect(layerThree, layerThree, flakeSize, flakeSize);
    ellipse(layerFour, layerFour, flakeSize, flakeSize);
  }
}


void mouseDragged() {
  if (mouseY > 10 && mouseY < 40 && mouseX > marginLeft && mouseX < (marginLeft + barWidth)) {
    handle1 = mouseX;
    flakeSize = mouseX;
  }
  if (mouseY > 50 && mouseY < 70 && mouseX > marginLeft && mouseX < (marginLeft + barWidth)) {
    handle2 = mouseX;

    layerTwo = mouseX / 2;
    layerThree = layerTwo + difference;
    layerFour = layerTwo + (difference * 2);
  }

  if (mouseY > 50 && mouseY < 130 && mouseX > marginLeft && mouseX < (marginLeft + barWidth)) {
    handle3 = mouseX - 20;
    handle3 = mouseX;
  }
}


float drawSlider(float xPos, float yPos, float sWidth, float sHeight,float hueVal){
  fill(255);
  noStroke();

  float sliderPos = map(hueVal, 0.0,255.0, 0.0, sWidth); //find the current sliderPosition from hueVal

  for(int i = 0; i < sWidth; i++){  //draw 1 line for each hueValue from 0-255
      float hueValue = map(i,0.0,sWidth,0.0,255.0);  //get hueVal for each i position //local variable
      stroke(hueValue,255,255);
      line(xPos+i,yPos,xPos+i,yPos+sHeight);
  }
  if(mousePressed && mouseX>xPos && mouseX<(xPos+sWidth) && mouseY>yPos-10 && mouseY <yPos+sHeight+10){
     sliderPos=mouseX-xPos;
     hueVal=map(sliderPos,0.0,sWidth,0.0,255.0); // get new hueVal based on moved slider
  }
  stroke(100);
  fill(hueVal,255,255); //either new or old hueVal
  translate(0, 0, 2);
  ellipse(sliderPos + xPos-3, yPos + 3, handleSize, handleSize); //this is our slider indicator that moves

  return hueVal;
}