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I have a problem: I can't figure out how to move a sprite with multiple keys pressed at once. A little more explanation: Button W moves the sprite Up Button S moves the sprite Down When pressed separately, it works just fine. The problems begin when I try to press several buttons at once. Problems: 1. Player presses W, and then S. What happens: W is ignored, S is processed. Sprite moves down. What is supposed to happen: Both W and S are processed. Sprite remains stationary (because both "UP" and "DOWN" buttons are pressed at once). 2. Player presses W, and then S, and then releases W. What happens: After the button is released, all the movement stops. What is supposed to happen: After W is released, sprite should move down as long as S is still held down. I tried to solve this using my own keypress handlers, but end up with either "infinite speedup while pressed" or the problem described above. I managed to do in with Python and Python - to - Javascript converter (basically a JS library that converts Python code into JS), but can't figure out how to do this using Phaser. Any help will be appreciated. The code I currently have (complicated): keyUP = this.input.keyboard.addKey(Phaser.Keyboard.W); keyUP.onDown.add(function() { this.movePlayer("left", "up", "pressed") }, this); keyUP.onUp.add(function() { this.movePlayer("left", "up", "released") }, this); keyDN = this.input.keyboard.addKey(Phaser.Keyboard.S); keyDN.onDown.add(function() { this.movePlayer("left", "down", "pressed") }, this); keyDN.onUp.add(function() { this.movePlayer("left", "down", "released") }, this);and movePlayer: function(player, direction, state) { var speedX = 0; var speedY = 0; if(player == "left") { if(direction == "up") { if(state == "pressed") { speedY = -175; } else if(state == "released") { //speedY -= -175; } } else if(direction == "down") { if(state == "pressed") { speedY = 175; } else if(state == "released") { //speedY -= 175; } } } else if(player == "right") { var addLater; } //this.playerLeft.body.velocity.y += -175; this.playerLeft.body.velocity.y = speedY; //console.log("total x:",speedX,"y:",speedY); }But it works absolutely the same as explained in tutorials - when W is pressed, set velocity to a fixed value, when W is released, set velocity to zero. I tried directly adding positive and negative values to velocity when a corresponding to key is pressed, but this leads to acceleration of the sprite (it goes faster and faster). And when I release the key, the sprite keeps moving in opposite direction (console.log made me realize there were more keyUp events than keyDown events, which is weird). What I'm trying to do: When W is pressed, increase velocity ONCE by a fixed value. When W is released, decrease velocity ONCE by same fixed value, thus stopping sprite. When both W and S are pressed, the total speed of sprite is 0 (because both add velocity in opposite directions but of same value). When one key is released and the other stays pressed, sprite is moving in that respective direction. And I can't figure out how to make this happen. I am using "onDown" because it was recommended here: http://www.html5gamedevs.com/topic/3803-question-about-keys-pressed-vs-isdown/ as the "happens once" solution. This post: http://www.html5gamedevs.com/topic/1922-justpressed-only-once/#entry35563 Makes me thing I'm making a horrible mistake here by using "movePlayer: function" instead of "function movePlayer(param){}" syntax somewhere else... but I haven't been able to figure out where the function goes. Outside of state curly brackets, maybe? When I add console.log to this function, it gets executed first 30+ times per second while button is pressed for a short period, and then thousands of times per second... does this mean that using "add" I keep adding more and more and more functions to be executed every time I press a button, leading to thousands of functions executed instead of one? If so, how do I solve this? I'm new to programming on Phaser, so any help is much appreciated. Trying to figure out how stuff works. My old code: if(this.keyboard.isDown(Phaser.Keyboard.W)) { this.playerLeft.body.velocity.y += -175; } else if(this.keyboard.isDown(Phaser.Keyboard.S)) { this.playerLeft.body.velocity.y += 175; } else { this.playerLeft.body.velocity.y = 0; }This leads to acceleration, not constant speed, and old problem with simultaneous presses remains. Using equals instead of incrementing fixes acceleration, but doesn't fix my main problem with simultaneous presses.