When testing D432, it was noticed that hero selection overlays become unsaturated when their position changes (even if they are still selected). rP16274 introduced this bug by setting m_AlphaMin and m_Color.a to MIN_ALPHA_ALWAYS_VISIBLE needlessly if the hero moved and was still inWorld.
m_Color.a and m_AlphaMin just need to be set to MIN_ALPHA_UNSELECTED (0) when the hero moves out of world.
(The selection overlay won't be rendered if m_Color.a is set to 0, saving some computations).