let axis;

let arrowArray = [];

// let heartPoints = []; // Array to store points on the heart

// let maxDistance = 300; // Maximum distance for point generation

// let sigma = 15; // Standard deviation for the Gaussian function

​

function setup() {

  createCanvas(windowWidth, windowHeight, WEBGL);

  axis = createGraphics(windowWidth, windowHeight, WEBGL);

  drawAxis();

  arrowArray.push(new Arrow(0, 0, 1000));

  /* Generate points on the heart to use as a reference

  for (let t = 0; t < TWO_PI; t += 0.01) {

    let x = functionHeartX(t);

    let y = functionHeartY(t);

    heartPoints.push(createVector(x + axis.width / 2, -y + axis.height / 2)); // Center the heart

  }*/

}

​

function draw() {

  background(10);

  lights();

  ambientLight(50);

  pointLight(

    255, 0, 0, // color

    0, 0, 0 // position

  );

  // frameRate(60);

  orbitControl();

​

  // use Graphics.axis as the texture of a plane

  // create 2D objects in 3D space

  texture(axis);

  plane(windowWidth / 1.2, windowHeight / 1.2);

  // display all arrows in arrowArray for 1 frame

  if (arrowArray[0]) {

    for (let i = 1; j = arrowArray[i] ;i += 1) {

      if (j._3Dz < -50) {

        arrowArray.splice(i, 1);

      } else {

        j.arrowDisplay();

      }

    }

  }

  // add new arrows to arrowArray

  if (mouseIsPressed) {

    let t = random(TWO_PI)

    let x = functionHeartX(t);

    let y = functionHeartY(t);

    arrowArray.push(new Arrow(x, -y, 1000));

    /* Check distance to the heart

    let closestDistance = Infinity;

    for (let heartPoint of heartPoints) {

      let d = dist(x + axis.width / 2, -y + axis.height / 2, heartPoint.x, heartPoint.y);

      if (d < closestDistance) {

        closestDistance = d;

      }

    }

​

    // Calculate probability using Gaussian decay

    let probability = gaussianProbability(closestDistance);

​

    // Add point based on probability

    if (random() < probability) {

      arrowArray.push(new Arrow(x, -y, 1000));

    }*/

  }

}

​

function drawAxis() {

  // translate to 2D coordinate system

  axis.translate(-axis.width / 2, -axis.height / 2);

  axis.background(10);

  // draw the axises

  axis.stroke('white');

  axis.line(0, axis.height / 2, axis.width, axis.height / 2);

  axis.line(axis.width / 2, 0, axis.width / 2, axis.height);

  // draw the marks on the y axis

  for (let i = 0; i < width; i += axis.height / 20) {

    axis.line(axis.width / 2, 

         0 + i, 

         axis.width / 2 + 5, 

         0 + i);

  }

  // draw the marks on the x axis

  for (let i = 0; i < width; i += axis.width / 20) {

    axis.line(0 + i, 

         axis.height / 2,

         0 + i,

         axis.height / 2 - 5);

  }

}

​

class Arrow {

  constructor (x, y, z) {

    this._3Dx = x;

    this._3Dy = y;

    this._3Dz = z;

  }

​

  // display the arrow for 1 frame

  arrowDisplay() {

    if (this._3Dz > 0) { // if the arrow hasn't reach the axis

      this._3Dz -= 10; // the speed in which the arrows move

    } else if (this._3Dz <= 0) {

      this._3Dz -= 0.01;

    }

    push();

    translate(this._3Dx, this._3Dy, this._3Dz);

    rotateX(PI / 2); // rotate to make the top/bottom facing the axis

    fill('white');

    noStroke();

    cylinder(2, 100);

    pop();

  }

}

​

function functionSine(x) {

  return 50 * sin(x * 0.05); 

}

​

// Heart shape function

function functionHeartX(t) {

  return 160 * pow(sin(t), 3);

}

​

function functionHeartY(t) {

  return 150 * cos(t) - 55 * cos(2 * t) - 30 * cos(3 * t) - 10 * cos(4 * t);

}

​

/* Gaussian probability function

function gaussianProbability(distance) {

  if (distance > maxDistance) {

    return 0; // No points beyond maxDistance

  }

  return exp(-pow(distance, 2) / (2 * pow(sigma, 2))); // Gaussian decay

} */

​