Question

I’m using http://craftyjs.com/ for the Github Game Off, and I’m having some trouble with animation. The first time I start the animation (when I initialize the player entity in the main scene) it works. But when I set the animation via my CustomControls component, it only plays the first frame of the animation.

I believe the problem is in the CustomControls component, so here’s the code for that:
https://gist.github.com/3992392

Here’s all the code if you want to clone it and test: https://github.com/RylandAlmanza/dragons-suck

If anyone knows what the problem might be, let me know. Thanks!

EDIT: Here’s a minimal jsfiddle example with everything stripped out except for movement and what should be animation: http://jsfiddle.net/x7FDF/

var SPRITE_SIZE = 32;
Crafty.init();
Crafty.canvas.init();
Crafty.sprite(SPRITE_SIZE, "http://i.imgur.com/9sN9V.png", {
    player_east_1: [0, 0],
    player_east_2: [1, 0],
    player_east_3: [2, 0],
    player_west_1: [0, 1],
    player_west_2: [1, 1],
    player_west_3: [2, 1],
    player_south_1: [0, 2],
    player_south_2: [1, 2],
    player_south_3: [2, 2],
    player_north_1: [0, 3],
    player_north_2: [1, 3],
    player_north_3: [2, 3]
});

Crafty.scene("loading", function() {
    Crafty.background("#000");
    Crafty.e("2D, DOM, Text")
    .attr({
        w: 100,
        h: 20,
        x: 150,
        y: 120
    })
    .text("Loading")
    .css({"text-align": "center"});
    Crafty.load(["http://i.imgur.com/9sN9V.png"], function() {
        Crafty.scene("main");
    });
});

Crafty.scene("main", function() {
    Crafty.background("#000");

    var player = Crafty.e("2D, DOM, SpriteAnimation, player_east_1, Collision, TileCollision, CustomControls")
    .attr({
        x: 0,
        y: 0,
        x_velocity: 0,
        y_velocity: 0,
        w: SPRITE_SIZE,
        h: SPRITE_SIZE
    })
    .animate("stand_east", 0, 0, 0)
    .animate("stand_west", 0, 1, 0)
    .animate("stand_south", 0, 2, 0)
    .animate("stand_north", 0, 3, 0)
    .animate("walk_east", [[0, 0], [1, 0], [0, 0], [2, 0]])
    .animate("walk_west", [[0, 1], [1, 1], [0, 1], [2, 1]])
    .animate("walk_south", [[0, 2], [1, 2], [0, 2], [2, 2]])
    .animate("walk_north", [[0, 3], [1, 3], [0, 3], [2, 3]])
    .animate("stand_east", 45, -1)
    .CustomControls();
});


Crafty.c("CustomControls", {
    CustomControls: function() {
        this.bind("EnterFrame", function() {
            var up = Crafty.keydown[Crafty.keys.UP_ARROW];
            var down = Crafty.keydown[Crafty.keys.DOWN_ARROW];
            var left = Crafty.keydown[Crafty.keys.LEFT_ARROW];
            var right = Crafty.keydown[Crafty.keys.RIGHT_ARROW];
            if (up) {
                this.y_velocity = -2;
                if (!this.isPlaying("walk_north")) {
                    this.stop().animate("walk_north", 45, -1);
                }
            }
            if (down) {
                this.y_velocity = 2;
                if (!this.isPlaying("walk_south")) {
                    this.stop().animate("walk_south", 45, -1);
                }
            }
            if (left) {
                this.x_velocity = -2;
                if (!this.isPlaying("walk_west")) {
                    this.stop().animate("walk_west", 45, -1);
                }
            }
            if (right) {
                this.x_velocity = 2;
                if (!this.isPlaying("walk_east")) {
                    this.stop().animate("walk_east", 45, -1);
                }
            }
            if (!left && !right) {
                this.x_velocity = 0;
                this.stop();
            }
            if (!up && !down) {
                this.y_velocity = 0;
                this.stop();
            }
            this.x += this.x_velocity;
            this.y += this.y_velocity;
        });
    }
});

Crafty.scene("loading");​

Answer 1

In the end of "enterFrame" you have:

if (!left && !right) {
    this.x_velocity = 0;
    this.stop();
}
if (!up && !down) {
    this.y_velocity = 0;
    this.stop();
}

Therefore, the animation is always stopped and then restarted from the beginning in the next frame. For example, when you’re player is moving down, (!left && !right) evaluates true and the animations is stopped.

One solution is to stop the animation only if all 4 directions are false.

if (!left && !right) {
    this.x_velocity = 0;
}
if (!up && !down) {
    this.y_velocity = 0;
}
if (!(up | down | left | right)) {
    this.stop();
}