I came across Bent Normals. I was wondering how to implement this in Unity because as far as I know, this is not supported out of the box.
To my understanding, bent normals are are shading improvement used in ambient occlusion (I guess they even won an Oscar for that, if I remember correctly). There are many ways to do AO, so give us some more details on your requirements and what it is that you are trying to achieve.
The naive way to use bent normals is to just use them instead of regular normal maps.
Crytek kind of does this, they use your basic normal maps for all content to start with and write that to a gbuffer, then calculate a bent normal during the SSAO pass, then all lighting is done with the bent normals and not the original normals.
For Unity overriding the deferred normals would take a bit (aka, a lot) more work to accomplish, but you can get part way there by just using pre-baked bent normal maps. Some people will use regular normal maps for the direct lighting and only bent normals for ambient lighting and non-shadowed lights.
Another nice hack for more organic objects is someone noticed that bent normals on lower poly models with highly detailed normal maps are often pretty close to the same as the original vertex normal, so you can just lerp from the normal map to vertex normal depending on the ambient occlusion map and get a close approximation of bent normals with out needing a bent normal map.
They’re all hacks on hacks on hacks though. At some point the approximation of an approximation stops being that close to the original thing that was trying to be approximated and it’s more about if the resulting look is something you find pleasing or not.
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Ok, thanks. I guess it will take a while before this is supported by Unity instead of us hacking their pipeline.
@Elecman and @bgolus as far as I know Bent Normals are supported in the HD asset for scriptable render pipeline. If this is the same kind of bent normal approach, I have no idea.
this would be really interesting. it is such old tech improving lighting a lot any news on this?