sprite.js

var

    s_dog,
    s_bg,
    s_fg,
    s_pipeNorth,
    s_pipeSouth,
    s_text,
    s_score,
    s_splash,
    s_buttons,
    s_numberS,
    s_numberB,
    s_medals;

function Sprite(img, x, y, width, height) {
    this.img = img;
    this.x = x * 2;
    this.y = y * 2;
    this.width = width * 2;
    this.height = height * 2;
};
Sprite.prototype.draw = function (ctx, x, y) {
    ctx.drawImage(this.img, this.x, this.y, this.width, this.height,
        x, y, this.width, this.height);
};

function initSprites(img) {

    s_dog = [
       // new Sprite(img, 156, 115, 17, 12),
       // new Sprite(img, 156, 128, 17, 12),
       // new Sprite(img, 156, 141, 17, 12)
       new Sprite(img, 215, 120, 36, 62),
       new Sprite(img, 252, 120, 27, 62),
        new Sprite(img, 271, 57, 34, 62)
    ];

    s_medals = {
        Bronze: new Sprite(img, 197, 137, 23, 23),
        Silver: new  Sprite(img, 197, 114, 23, 23),
        Gold: new Sprite(img, 173, 137, 23, 23),
        Platinum: new Sprite(img, 173, 114, 23, 23)
    },

        s_bg = new Sprite(img, 0, 0, 138, 114);
    s_bg.color = "#70C5CF";
    s_fg = new Sprite(img, 138, 0, 160, 26);

    //s_pipeNorth = new Sprite(img, 251, 0, 10, 200);
    s_pipeNorth = new Sprite(img, 253, 57, 20, 35);
    //s_pipeSouth = new Sprite(img, 277, 0, 10, 200);
    //pajaro
    s_pipeSouth = new Sprite(img, 283, 126, 14, 14);

    s_text = {
        Flappydog: new Sprite(img, 59, 114, 96, 22),
        GameOver: new Sprite(img, 59, 136, 94, 19),
        GetReady: new Sprite(img, 59, 155, 87, 22)
    }
    s_buttons = {
        Rate: new Sprite(img, 79, 177, 40, 14),
        Menu: new Sprite(img, 119, 177, 40, 14),
        Share: new Sprite(img, 159, 177, 40, 14),
        Score: new Sprite(img, 79, 191, 40, 14),
        Ok: new Sprite(img, 119, 191, 40, 14),
        Start: new Sprite(img, 159, 191, 40, 14),
        Test : new Sprite(img, 119,177,40,14)
    }

    s_score = new Sprite(img, 138, 56, 113, 58);
    s_splash = new Sprite(img, 0, 130, 59, 39);

    s_numberS = new Sprite(img, 0, 177, 6, 7);
    s_numberB = new Sprite(img, 0, 188, 7, 10);

    s_numberS.draw = s_numberB.draw = function (ctx, x, y, num, center, offset) {
        num = num.toString();
        var step = this.width + 2;

        if (center) {
            x = center - (num.length * step - 1) / 2;
        }

        if (offset) {
            x += step * (offset - num.length);
        }

        for (var i = 0, len = num.length; i < len; i++) {
            var n = parseInt(num[i]);
            ctx.drawImage(img, step * n, this.y, this.width, this.height,
                x, y, this.width, this.height)
            x += step;
        }
    }
}