How much access do we have to the lighting pre-pass in deferred rendering?

Unity Engine
1

Hi guys, I realise this question is kind of open, but my team is preparing to embark on a journey where we plan to do lots of weird stuff with lighting.

I’m not all that familiar with deferred rendering in Unity, however I understand the core concept very well as I’ve used it in other engines.

Basically, I want to know how much access we have to the lighting pre-pass in Unity. I haven’t had a lot of free time to investigate this yet, But so far I can’t find more control than simply enabling it, and altering settings on my lights. There are a few additional setting in the Quality pane, but nothing that really lets us get into it’s guts.

The kind of things I’m looking to be able to do is blend dual shadow maps, cast shadows from lights, some crazy stuff like using particles to create shadows in weird places, and maybe even some image effects like bloom in the shadow channel. One key effect though is that I will have a large map indicating a characters field of view, that I would like to be able to draw as an overlay as well.

A lot of this is pretty weird stuff, but we’re quite confidant in the look we’ve come up with,. I just have no idea if this is possible in Unity. If the lighting prepass simply behaved like some kind of texture or camera that we can do what we like with, we would be very happy.

Can anyone shed any light (hehe) on how this is handled in Unity, and if we can access that level of functionality? I’m a coder, so if there is any way of accessing this kind of stuff at a lower level, I’m fine with that.

Thanks a lot
Dave

2

*** bump

Is no one answering because it’s a stupid question, or nobody knows?

Modifying how different passes render is pretty common in AAA games these days, but I’m wondering if it’s possible in any way in unity.For example, in Killzone 3, alan wake, and others, it’s known that they do a lot of post processing and blending to their lighting pass before it gets combined with the geometry.

Even if the answer is a gruff “no”, I think it would give me some closure.

Perhaps a few more examples of the things we are wanting to prototype. Something the triggers all of the shadows to defocus and distort. Having shadows aren’t certain creature “bloom” out, like you would with a bright light. Having shadows eliminated by certain creature that pass through them.

I realise there would be ways to do things like this if I simply had bigger complex lighting setups, but that’s really not the effect we are going for. Is there any way to edit the shaders, or the actual pass, or post process what gets generated, in the deferred lighting pass?

I can only find switches and toggles for the built in features.

Thanks again
Dave

3

I’m not able to answer this question, but doing a Google search for “custom lighting deferred Unity” brings up some links such as this one (Daniel’s answer at the bottom):

http://forum.unity3d.com/threads/105299-Deferred-Rendering-Custom-Lighting