CC024: Perlin Noise Flow Field

// Coding Challenge #78: Perlin Noise Flow Field

​

FlowField field;

ArrayList < ParticleSystem > drops;

int init_drop_num = 1;

​

color[] color_options = {

  color(0, 0, 0),

  color(41, 52, 98),

  color(247, 98, 98),

  color(255, 241, 193),

  color(76, 108, 118)

};

​

int color_index = 0;

int drop_counter = 0;

​

void setup() {

  //size(800, 800);

  fullScreen();

​

  // init field

  field = new FlowField(20);

  field.update();

  field.updatePScale(10);

  field.updatePRate(0.1);

  field.updatePStrength(2);

​

  // start with 1 drop

  drops = new ArrayList < ParticleSystem > ();

  drops.add(new ParticleSystem());

  drops.get(drop_counter).setColor(color(0));

  drop_counter++;

​

  // start with blank canvas

  background(255);

}

​

void draw() {

  // compute field

  field.update();

​

  // run each drop

  for (ParticleSystem d: drops) {

    d.update(field);

  }

​

  // color bar

  drawBar(color_options);

}

​

void drawBar(color[] in_colors) {

  int num_colors = in_colors.length;

  float seg_width = width / num_colors;

  float seg_height = height * 0.05;

  // set color

  int color_index = floor(map(mouseX, 0, width, 0, num_colors));

  color color_show = in_colors[color_index];

  drops.get(0).setColor(color_show);

  // render bar

  for (int i = 0; i < num_colors; i++) {

    fill(in_colors[i]);

    noStroke();

    rect(i * seg_width, height - seg_height,

      seg_width, seg_height);

  }

}