public void drawTrail(ref SpriteBatch batch, ref Trail trail)
{
Color _color = Color.White;
for (int i = Trail.SIZE - 1; i >= 0; i--)
{
_color.A = (byte)((trail.Positions.Count - i) * (255 / trail.Positions.Count));
trail.updateRectangle(i);
batch.Draw(textures["Pandas"], trail.Rectangle, trail.Sources[i], _color);
}
}