snake — Jack's Game — Coding Academy

let speed = 2;
let direction = "down";
const segmentSpacing = 40; // how far apart the tail segments should be
const segmentsToIgnoreNearHead = 2; // these sit too close to the head to ever NOT be touching it

function die(){
    UI.showMessage("Game Over!","red");
    UI.showButton("Restart",Game.restart);
}

export function update(self, keys) {

Game.setBackgroundImage("Birdy Bird/Backgrounds/3.png");

if (self.tail === undefined) {
        self.tail = [];
        self.trail = [];
    }

UI.drawText("Score:"+(self.tail.length),32,32,"white");

// 1. Calculate dynamic speed based on tail length
    const baseSpeed = 2;
    const maxSpeed = 6;
    speed = Math.min(maxSpeed, baseSpeed + self.tail.length * 0.2);

// Move our snake & set head rotation
    if(direction == "down"){
        self.setY(self.getY() + speed);
        self.setRotation(0);
    }
    if(direction == "up"){
        self.setY(self.getY() - speed);
        self.setRotation(180);
    }
    if(direction == "left"){
        self.setX(self.getX() - speed);
        self.setRotation(90);
    }
    if(direction == "right"){
        self.setX(self.getX() + speed);
        self.setRotation(270); // Corrected from 90 -> 270 for facing right
    }

// Change our direction
    if(keys.upPressed){
        direction = "up";
    }
    if(keys.downPressed){
        direction = "down";
    }
    if(keys.leftPressed){
        direction = "left";
    }
    if(keys.rightPressed){
        direction = "right";
    }

// Die if we hit a wall
    if(self.getX() >= window.innerWidth-30){
        die();
    }
    if(self.getX() < 30){
        die();
    }
    if(self.getY() < 30){
        die();
    }
    if(self.getY() >= window.innerHeight-30){
        die();
    }

// 1. Record both position AND rotation in the trail history
    self.trail.unshift({ 
        x: self.getX(), 
        y: self.getY(), 
        rotation: self.getRotation() 
    });

const framesPerSegment = Math.max(1, Math.round(segmentSpacing / speed));
    self.trail.length = Math.min(self.trail.length, self.tail.length * framesPerSegment + 1);

// 2. Apply both position and rotation to each segment
    for (let i = 0; i < self.tail.length; i++) {
        const segment = Game.getShape(self.tail[i]);
        const spot = self.trail[(i + 1) * framesPerSegment];
        if (segment && spot) {
            segment.setX(spot.x);
            segment.setY(spot.y);
            segment.setRotation(spot.rotation); // Sets the delayed rotation
        }
    }

// Die if we run into our own tail
    for (let i = segmentsToIgnoreNearHead; i < self.tail.length; i++) {
        if (self.isTouching(self.tail[i])) {
            die();
        }
    }

if (self.isTouchingOnce("cube1")) {
        const lastSegmentId = self.tail.length > 0 ? self.tail[self.tail.length - 1] : null;
        const lastSegment = lastSegmentId ? Game.getShape(lastSegmentId) : null;
        const spawnX = lastSegment ? lastSegment.getX() : self.getX();
        const spawnY = lastSegment ? lastSegment.getY() : self.getY();
        const newSegmentId = Game.spawnShape("circle", spawnX, spawnY, "lime", 30, "Mega Turrets/Enemies/Grounds Enemy/BlueBeetle/BlueBeetle-move_01.png");
        self.tail.push(newSegmentId);
    }
}

self.getX()/getY()/setX()/setY() · move it | self.setColor('red') · change its color | self.setTexture('patterns/checker.png') · pick a texture, or null for plain color | self.isTouching('circle1') · true every frame while overlapping | self.isTouchingOnce('circle1') · true once, the frame contact starts | Game.getShape('circle1').health -= 1 · read/change another shape's stuff | Game.spawnShape('circle', x, y, 'red') · create a new shape, returns its id | keys.left/right/up/down/space · held down (smooth movement) | keys.leftPressed/rightPressed/... · just pressed once (hop movement, like Frogger) | UI.showMessage('Game Over!') · popup + freeze | UI.showButton('Play Again', Game.restart) · clickable button | UI.drawText('Health: 100', 20, 20) · call every frame to keep it showing | Game.restart() · reset to starting positions

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Jack's Game: snake

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