Why does collision fail when I increase span time to less than 1000ms or increate gravity of an item?

[ciscog]

I'm working on my first game that's pretty close to done, I'm just tweaking it to make it just a little bit more challenging.  It's just a fun little thing I made as an extra show piece for a website my friend is building and to learn how to make a game.  Right now I have a random item spawning once a second, it gets added to a group, is set to kill on out of bounds, and has physics arcade enabled on it.  

 

Here are current issues:

1. collision happens but halfway through the player sprite.  I think this might be related to the anchor point being in the middle of the item sprite but if I change that then I loose rotation on the center of the item
2. I tried to implement a random spawn time between 500 - 1500ms but any of the items spawned under 1000ms just went right through my player sprite
3. I tried randomizing the gravity.y of an item sprite upon spawning but again the faster ones just go straight through the player sprite

Is collision detection slow?

 

am I doing something wrong?  

 

I just want to add a simple amount more of challenge to the game.  

 

playable game:

http://www.franciscog.com/sk-game/

debug mode: http://www.franciscog.com/sk-game/?debug

 

click on game or press up to start

press M to mute music (only music is muted so far)

 

 

full game code here:

https://github.com/FranciscoG/sk-game/blob/master/game/game.js

 

here's my Play state create function: (skGame is the main object and holds some globals)

create: function () {    var h = skGame.h, w = skGame.w;    // add the background    game.add.sprite(0, 0, 'bg');    // initiate game physics    game.physics.startSystem(Phaser.Physics.ARCADE);    game.physics.arcade.gravity.y = 200;    game.physics.arcade.setBounds(0, 0, w, h - 29);    // setup score    skGame.score = 0;    this.scoreText = game.add.text(10, 10, "0", { font: '30px Arial', fill: '#fff'});    // inituate cursor key inputs    this.cursor = game.input.keyboard.createCursorKeys();    // create Group of items    //this.spawnItemTimer = 0;    this.itemGroup = game.add.group();    this.itemGroup.setAll('outOfBoundsKill', true);    this.spawnItem();    // add hearts to screen    this.health = 3;    this.heartGroup = game.add.group();    var heart,        i = this.health,        x = w - 40;    while (i > 0) {      heart = game.add.sprite(x, 10, 'heart');      this.heartGroup.add(heart);      x = x - 35;      i--;    }        // add the player to the screen    this.player = game.add.sprite(w/2, h - 30, 'player');    this.player.anchor.setTo(0.5,0);        // setup player    this.player.animations.add('run', [1,2,3,4,5,6,7,8], 15, true);    this.player.animations.add('hurt', [9,10], 15, true);    this.isHurt = false;    game.physics.arcade.enable(this.player);    this.player.body.collideWorldBounds = true;    // shrink the bounding box of the player because there's some transparent    // space that allows collisions    var heightOffset = 0;    this.player.body.setSize(60, 110 + heightOffset, 0, 0 - heightOffset);    //audio    this.sounds = {};    // sound FX    this.sounds.pickup = game.add.audio('pickup');    this.sounds.coin = game.add.audio('coin');    this.sounds.hurt = game.add.audio('hurt');    this.sounds.necklace = game.add.audio('necklace');    // create spawnItem loop    this.looping = game.time.events.loop(1000, this.spawnItem, this);    // init mute key    skGame.mute();        // show item paths in debug mode    this.showColumns();  },

here's my update function:  
 

update: function() {    var h = skGame.h, w = skGame.w, score = skGame.score;    // rotate the item    this.itemGroup.forEachAlive(function(item){        item.angle += item.rotateMe || 0;    });        this.player.body.velocity.x = 0;    // if player is hurt do this    if (this.isHurt) {      this.player.animations.play('hurt');      if (this.game.time.now - this.hurtTime >= 500) {        this.isHurt = false;      }    }    // when player is moving    if (!this.isHurt){      if (this.cursor.left.isDown) {        this.player.body.velocity.x = -350;        this.player.animations.play('run');        this.player.scale.x = 1;      } else if (this.cursor.right.isDown) {         this.player.body.velocity.x = 350;         this.player.scale.x = -1;         this.player.animations.play('run');      } else {        this.player.frame = 0;      }    }  },

and here's my Spawn Item function:

spawnItem: function() {    var h = skGame.h, w = skGame.w;    // I want the items to fall in specific columns on the screen so first I need to    // figure out how many columns available that are the width of the sprite    var spriteW = 60;    var sp = Math.floor(w / spriteW); // calc number of columns in stage    var dropPos = rand(sp); // get random column    // now place it on screen by adding it to a group    var itemX = dropPos * spriteW + (spriteW/2);    var item = game.add.sprite(itemX, 0, 'items', null, this.itemGroup);    // get a random Item from the spritesheet. 11 items total    var itemType = rand(11);    if (itemType === 10) {      item.animations.add('blink', [17,18], 10, true);      item.animations.play('blink');      item.itemName = "necklace";    } else if (itemType === 9) {      item.animations.add('coin_twirl', [9,10,11,12,13,14,15,16], 10, true);      item.animations.play('coin_twirl');      item.itemName = "coin";    } else if (itemType <= 5 ) {      item.itemName = "normal_item";      item.frame = itemType;    } else { // items 6,7,8      item.itemName = "bad_item";      item.frame = itemType;    }    item.rotateMe = (Math.random()*4)-2;    // enable physics    game.physics.enable(item, Phaser.Physics.ARCADE);        // shrink the bounding box of the item because there's some transparent area    item.body.setSize(55, 60, 0, 0);    item.anchor.setTo(0.5, 0.5);    game.physics.arcade.overlap(this.player, this.itemGroup, this.grabItem, null, this);  },

thanks!

[rich]

I can't see anywhere in your update loop a call to arcade.collide (or even arcade.overlap). I see it once in the spawnItem box, but all that will do is check the item once, when it's very first spawned - surely you need to be checking it every single frame?