car.js

class Car{
  constructor(x, y, width, height, controlType, maxSpeed = 4){
    this.x = x;
    this.y = y;
    this.width = width;
    this.height = height;

    this.speed = 0;
    this.acceleration = 0.2;
    this.maxSpeed = maxSpeed;
    this.friction = 0.05;
    this.angle= 0;
    this.damaged = false;

    this.useBrain = controlType == "AI";

    if(controlType != "DUMMY"){
      this.sensor = new Sensor(this);
      this.brain = new NeuralNetwork(
        [this.sensor.rayCount, 6, 4]
      )
    } //@dev This if statement allows the self-driving car to have sensors and a neural network
    this.controls = new Controls(controlType);
  }
  //@dev param1 & 2 define where we want the car to be
  //@dev param3 & 4 define how big we want the car to be

  update(roadBorders, traffic){
    if(!this.damaged){
      this.#move();
      this.polygon = this.#createPolygon();
      this.damaged = this.#assessDamage(roadBorders, traffic);
    }
    if(this.sensor){
      this.sensor.update(roadBorders, traffic);
      const offsets = this.sensor.readings.map(s => s == null ? 0 : 1 - s.offset)
      //@dev This map creates nuances in perceiving whether or not it is close to a border,
      // if it is close, the number will be closer to 1 and if far it will be 0
      const outputs = NeuralNetwork.feedForward(offsets, this.brain);

      if (this.useBrain) {
        this.controls.forward = outputs[0];
        this.controls.left = outputs[1];
        this.controls.right = outputs[2];
        this.controls.backward = outputs[3];
      }
    } //@dev This if statement only updates sensors if a given car has a sensor
  }

  #assessDamage(roadBorders, traffic){
    for (let i = 0; i < roadBorders.length; i++) {
      if(polysIntersect(this.polygon, roadBorders[i])){
        return true;
      }
    }

    for (let i = 0; i < traffic.length; i++) {
      if(polysIntersect(this.polygon, traffic[i].polygon)){
        return true;
      }
    }
    return false;
  }

  #createPolygon(){
    const points = [];
    const rad = Math.hypot(this.width, this.height) / 2;
    const alpha = Math.atan2(this.width, this.height);

    points.push({
      x: this.x - Math.sin(this.angle - alpha) * rad,
      y: this.y - Math.cos(this.angle - alpha) * rad
    });

    points.push({
      x: this.x - Math.sin(this.angle + alpha) * rad,
      y: this.y - Math.cos(this.angle + alpha) * rad
    });

    points.push({
      x: this.x - Math.sin(Math.PI + this.angle - alpha) * rad,
      y: this.y - Math.cos(Math.PI + this.angle - alpha) * rad
    });

    points.push({
      x: this.x - Math.sin(Math.PI + this.angle + alpha) * rad,
      y: this.y - Math.cos(Math.PI + this.angle + alpha) * rad
    });

    return points
  } //@dev This function defines the four corners of the car

  #move(){
    if(this.controls.forward){
      this.speed += this.acceleration;
    }

    if(this.controls.backward){
      this.speed -= this.acceleration;
    }

    if(this.speed > this.maxSpeed){
      this.speed = this.maxSpeed;
    }

    if(this.speed < -this.maxSpeed / 2){
      this.speed = -this.maxSpeed / 2;
    }

    if(this.speed > 0){
      this.speed -= this.friction;
    }

    if(this.speed < 0){
      this.speed += this.friction;
    }

    if(Math.abs(this.speed) < this.friction){
      this.speed = 0;
    }

    if(this.speed != 0){
      const flip = this.speed > 0? 1 : -1;

      if(this.controls.left){
        this.angle += 0.03 * flip;
      }

      if(this.controls.right){
        this.angle -= 0.03 * flip;
      }
    }

    this.x -= Math.sin(this.angle) * this.speed;
    this.y -= Math.cos(this.angle) * this.speed;
  }

  draw(ctx, color, drawSensor = false){
    if(this.damaged){
      ctx.fillStyle = "gray";
    } else {
      ctx.fillStyle = color;
    }
    ctx.beginPath();
    ctx.moveTo(this.polygon[0].x, this.polygon[0].y);
    for (let i = 1; i < this.polygon.length; i++) {
      ctx.lineTo(this.polygon[i].x, this.polygon[i].y);
    } //@dev This loop draws the polygon connecting all points
    ctx.fill();
    if(this.sensor && drawSensor){
      this.sensor.draw(ctx);
    } //@dev This if statement only draws sensors if a given car has sensors
  }
}