Some trouble with shader rendering a raycast sphere with depth texture and mesh geometry

[masonblier]

I recently followed Sebastian Lague's planets videos but using Bevy instead. These use a post processing shader to render ocean and atmosphere effects using a raycast.

Repository here: https://github.com/masonblier/planet_test
Relevant code is here https://github.com/masonblier/planet_test/blob/main/assets/shaders/post_processing.wgsl

Unfortunately there is a problem with how I'm doing the ray cast, or maybe how I'm calculating world position from the depth texture. I copied depth_ndc_to_view_z from view_transformations.wgsl in the bevy_pbr crate, I assume that is correct. Perhaps I am casting the ray from an incorrect origin?

Any insights or ideas are greatly appreciated. Thanks, and thanks to everyone for contributing to Bevy!