setSpriteDirection

/**
  * Sets the direction the sprite faces based on it's velocity.
  * Faces the sprite in it's opposite direction when velocity is < 0
  * Assumes the sprite is facing right when its horizontal scale is < 0
  *
  * @param sprite The sprite to set the direction of. Must have arcade physics enabled on it.
  */
function setSpriteDirection(sprite: Phaser.Sprite) {
    let horVelocity = sprite.body.velocity.x;
    let horScale = sprite.scale.x;

    let velSign = GeneralHelpers.signum(horVelocity);
    let scaleSign = GeneralHelpers.signum(horScale);

    if (horVelocity !== 0 && scaleSign !== velSign) {
        let absScale = Math.abs(horScale);

        sprite.scale.x = velSign === 1 ? absScale : absScale * -1;
    }

}