Realistic Camera for the FirstPersonMovement script

var FirstPersonMovement = pc.createScript('firstPersonMovement');

FirstPersonMovement.attributes.add('camera', {
    type: 'entity',
    description: 'Optional, assign a camera entity, otherwise one is created'

FirstPersonMovement.attributes.add('power', {
    type: 'number',
    default: 2500,
    description: 'Adjusts the speed of player movement'

FirstPersonMovement.attributes.add('lookSpeed', {
    type: 'number',
    default: 0.25,
    description: 'Adjusts the sensitivity of looking'

// initialize code called once per entity
FirstPersonMovement.prototype.initialize = function() {
    this.force = new pc.Vec3();
    this.eulers = new pc.Vec3();
    var app =;
    // Listen for mouse move events
    app.mouse.on("mousemove", this._onMouseMove, this);

    // when the mouse is clicked hide the cursor
    app.mouse.on("mousedown", function () {
    }, this);            

    // Check for required components
    if (!this.entity.collision) {
        console.error("First Person Movement script needs to have a 'collision' component");

    if (!this.entity.rigidbody || this.entity.rigidbody.type !== pc.BODYTYPE_DYNAMIC) {
        console.error("First Person Movement script needs to have a DYNAMIC 'rigidbody' component");

// update code called every frame
FirstPersonMovement.prototype.update = function(dt) {
    // If a camera isn't assigned from the Editor, create one
    if (! {
    var force = this.force;
    var app =;

    // Get camera directions to determine movement directions
    var forward =;
    var right =;

    // movement
    var x = 0;
    var z = 0;

    // Use W-A-S-D keys to move player
    // Check for key presses
    if (app.keyboard.isPressed(pc.KEY_A) || app.keyboard.isPressed(pc.KEY_Q)) {
        x -= right.x;
        z -= right.z;

    if (app.keyboard.isPressed(pc.KEY_D)) {
        x += right.x;
        z += right.z;

    if (app.keyboard.isPressed(pc.KEY_W)) {
        x += forward.x;
        z += forward.z;

    if (app.keyboard.isPressed(pc.KEY_S)) {
        x -= forward.x;
        z -= forward.z;

    // use direction from keypresses to apply a force to the character
    if (x !== 0 && z !== 0) {
        force.set(x, 0, z).normalize().scale(this.power);

    // update camera angle from mouse events, this.eulers.x, 0);

FirstPersonMovement.prototype._onMouseMove = function (e) {
    // If pointer is disabled
    // If the left mouse button is down update the camera from mouse movement
    if (pc.Mouse.isPointerLocked() || e.buttons[0]) {
        this.eulers.x -= this.lookSpeed * e.dx;
        this.eulers.y -= this.lookSpeed * e.dy;

FirstPersonMovement.prototype._createCamera = function () {
    // If user hasn't assigned a camera, create a new one = new pc.Entity();"First Person Camera");"camera");
    this.entity.addChild(;, 0.5, 0);

Hello. This is kind of a problem. I wanted to make a game with the FirstPersonMovement script without the camera doing full front flips/back flips. (Basically going upside down.) And I also wanted to add bobbing. But, I have absolutely no idea what i’m doing.

Hi @AmericanHero999,

You can use the pc.math.clamp method to restrict the range of allowed values for the rotation around the x axis, that will eliminate the camera flipping.

For bobbing what usually developers do is add to the Y position of the body a Math.Sin() based offset. Here is a Unity post with a simple code snippet that you can implement in JS/Playcanvas:

How would I put this in the code? I tried

pc.math.clamp = max.y (90); 

I’m also having difficulties with the bobbing.

No, check the docs link I’ve posted above, the clamp method requires 3 parameters. You should be doing something like this as the last step of your angle calc code:

// values are random min/math, add your own
this.eulers.x = pc.math.clamp( this.eulers.x, 0, 90);

It’s true that this requires some semi-advanced math methods to get right. I’d recommend you first do some JS and vector math tutorials to start feeling comfortable with that kind of code.

Ah, alright. Thank you, Leonidas.

I’ll try reading the tutorials when I have time! ^-^

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