car.js

class Car {
    constructor(x, y, width, height, controlType, maxSpeed=3) {
        this.x = x; // x axis
        this.y = y; // y axis
        this.width = width;
        this.height = height;

        this.speed = 0;
        this.acceleration = 0.2;
        this.maxSpeed = maxSpeed;
        this.friction = 0.05; // tarcie
        this.angle = 0; // for better animation on turn left/right

        this.damaged = false;

        this.useBrain = controlType == "AI";

        if(controlType != "DUMMY") {
            this.sensor = new Sensor(this);
            this.brain = new NeuralNetwork([this.sensor.rayCount, 6, 4]);
        }
        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);
            const offsets = this.sensor.readings.map(
                s => s == null ? 0 : 1 - s.offset
            );
            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.reverse = outputs[3];
            }
        }
    }

    #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 = [];
        // redius -> distance from center to sides and corners 
        const rad = Math.hypot(this.width, this.height) / 2; // hypotenuse / 2
        const alpha = Math.atan2(this.width, this.height); // angel
        points.push({  // top right point
            x: this.x - Math.sin(this.angle - alpha) * rad,
            y: this.y - Math.cos(this.angle - alpha) * rad
        });
        points.push({ //top left point
            x: this.x - Math.sin(this.angle + alpha) * rad,
            y: this.y - Math.cos(this.angle + alpha) * rad
        });
        points.push({ // bottom right
            x: this.x - Math.sin(Math.PI + this.angle - alpha) * rad,
            y: this.y - Math.cos(Math.PI + this.angle - alpha) * rad
        });
        points.push({ // bottom left
            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(this.speed > 0) {
            this.speed -= this.friction;
        }
        if(this.speed < 0) {
            this.speed += this.friction;
        }
        if(Math.abs(this.speed) < this.fraction) {
            this.speed = 0;
        }

        if(this.speed != 0) {
            const flip = this.speed > 1 ? 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);
        }
        ctx.fill();

        if(this.sensor && drawSensor){
            this.sensor.draw(ctx); // car has responsibility to draw his own sensors
        }
    }
}