Sprite randomly stuttering when velocity is set

[vidhu]

I have a small sprite and I set its velocity.y=200 so it moves down. This works however, sometimes it moves smooth as silk. The other times it stutters a lot. I have no clue why this happens. Its like the frame rates drop to around 20fps from 60fps

 

Here is my code for this simple this. What am I doing wrong and how can I fix it?

var SimpleGame = (function () {    function SimpleGame() {        this.game = new Phaser.Game(800, 400, Phaser.AUTO, 'content', { preload: this.preload, create: this.create, update: this.update });    }    SimpleGame.prototype.preload = function () {        this.game.load.image('logo', 'Sprites/icon.png');    };    SimpleGame.prototype.create = function () {        //Create Sprite        this.speed = 133;        this.game.stage.backgroundColor = 0xffffff;        this.logo = this.game.add.sprite(this.game.world.centerX, this.game.world.centerY, 'logo');        this.logo.position.set(200, 50);        this.game.physics.arcade.enable(this.logo);        //Set velocity        this.logo.body.velocity.y = this.speed;    };    SimpleGame.prototype.update = function () {        if (this.logo.position.y >= 400) {            this.logo.body.velocity.y = -this.speed;        }        else if (this.logo.position.y <= 0) {            this.logo.body.velocity.y = this.speed;        }    };    return SimpleGame;})();window.onload = function () {    var game = new SimpleGame();};

You can also test it here http://chest.vidhucraft.com/PhaserTest/ to see the stuttering

[imLeyenda]

Same issue here, any solution?.

 

Greetings

[Batzi]

What if you do this instead

if(condition) this.logo.body.velocity.y -= this.speed;else this.logo.body.velocity.y += this.speed;

[san40511]

you've set sprite anchor to center.  and that's why cropped the half 

 

SimpleGame.prototype.update = function () {        if (this.logo.position.y >= 400-this.logo.height/2) {            this.logo.body.velocity.y = -200;        }        else if (this.logo.position.y <= this.logo.height/2) {            this.logo.body.velocity.y = 200;        }    };

About stutters. Everything works fine for me.

[nobody]

Try:

- Use CANVAS and not AUTO (WebGL is slow in Firefox)

 

Note that Phaser uses physicstime and not the real time to render things. If for example firefox is loading another tab, the animation will stutter.