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 (yzergame.com)

wireframe

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.

Thanks.

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Hi! I’ve made two UE implementations of this technique, one using a procedural mesh component to deform the mesh on tick, and one using a vertex shader on a special kind of mesh with some extra data baked into it. This actually works for any convex planar shape, not just for quad or rectangles. Available on GitHub as a plugin.

https://hollowdilnik.com/2022/06/20/doom-glow.html

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Amazing, thank you for sharing!
I tried your plugin in UE5 and it works perfectly! Just a minor change in the material function was necessary, swap back from the custom node “HMD position” to camera position and then it works on mobile to.
And it’s also pretty cheap on shader instructions and all these extra functions for custom shapes!

Do you have any plans on putting it on the marketplace or do you have a donation page? - Because I’ll use it extensively in my project. :slight_smile:

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Interesting, thanks for letting me know, I’ll see if I can make it work both in VR and flat mobile. I didn’t have any problems with mobile preview, but I’m using 4.27 and Vulkan for Android.

I don’t have a donation page, but I’d love to put this plugin on the marketplace at some point. I’ll let you know if I do, thanks!