Revert "Planet no atmosphere pixel shader"

This reverts commit c774d299218eb30bac5372cb939704f68b4431c3.
Revert "Revert "Planet no atmosphere pixel shader""

This reverts commit 65ab9995e2b1d43059a549e699f045565d2eec10.
Revert "Revert "Revert "Planet no atmosphere pixel shader"""

This reverts commit a6f5e7a4daa35a141ee2812ee563e7057843fd32.