Any idea on how to recreate dooms volumetric glow with vertex shader?

Hi there,
because there is no (cheap) bloom for mobile without mobileHDR I am searching for a low performance alternative. Some years ago I stumbled upon Simons Blog and his analysis of Dooms volumetric glow: Doom 3 – Volumetric Glow | Simon schreibt.

And someone implemented it with a breakdown in his game: Yzer development picture dump (


But my goal is to not rely on game code to update the vertices, but instead have the vertex shader push around the vertices. Maybe someone with better knowledge in math can help me out.


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