car.js

class Car {
    constructor(x, y, width, height, controlType, maxSpeed=3) {
        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;
        if (controlType != "dummy") {
            this.sensor = new Sensor(this);
        }
        
        this.controls = new Controls(controlType);
    }

    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);
        }
    }

    #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;  // half of hopotenus of the pologon
        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;
    }

    #move() {
        if (this.controls.forward) {
            this.speed += this.acceleration;
        }
        if (this.controls.reverse) {
            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 (Math.abs(this.speed) < this.friction) { // not having this if will result in that the car will move with a small speed constantly
            this.speed = 0;
        }
        if (this.speed > 0) {
            this.speed -= this.friction;
        }
        if (this.speed < 0) {
            this.speed += this.friction;
        }
        if (this.controls.left) {
            // this.x -= 2;
            this.angle += 0.03;
        }
        if (this.controls.right) {
            // this.x += 2;
            this.angle -= 0.03;
        }
        // this.y -= this.speed; // not real enough
        this.x -= Math.sin(this.angle)*this.speed;
        this.y -= Math.cos(this.angle)*this.speed;
    }

    draw(ctx, color) {
        // ctx.save();
        // ctx.translate(this.x, this.y);
        // ctx.rotate(-this.angle);
        // ctx.beginPath();
        // ctx.rect(-this.width/2, -this.height/2, this.width, this.height);
        // ctx.fill();
        // ctx.restore();
        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);
        }
        ctx.fill();
        if (this.sensor) {
            this.sensor.draw(ctx);
        }
    }
}