public void draw(Camera camera, SpriteBatch spriteBatch, Texture2D particleTexture)
        {
            //rita ut partiklar
            for (int i = 0 ; i< numParticles; i++) {

                if (particles [i] != null) {
                    Particle toBeRendered = particles [i];
                    Vector2 screenPos = camera.getViewFromModelPosition (toBeRendered.centerModelPosition);

                    spriteBatch.Draw (particleTexture,
                                     screenPos,
                                     particleTexture.Bounds,
                                     Color.White, 3.14f / 2.0f,
                                     new Vector2 (particleTexture.Bounds.Width / 2, particleTexture.Bounds.Height / 2),
                                     0.1f, SpriteEffects.None, 0);
                }
            }
        }