Deferred lighting actually slower then forward lighting?

Unity Engine
1

I’ve switched my project over to deferred lighting, which I thought would improve performance in my scene with 5 lights, but my frame rate has actually cut in half (from about 150 to 60 and bellow). Not only that, but everything in the scene is static, with baked lightmaps. What is the goings on?!

I’d be happy to supply more details about my project if needed, but I figured I’d check to see if this is just a common thing, with a well known explanation.

Thanks for any input!
Orion

PS. Also, just wanted to check- when I switched to Deferred Lighting, my Antialiasing went away. From what I’ve found in these forums it seems like Antialiasing just isn’t supported with deferred lighting, though people fake it with an edge blur filter (which is working fine for me)- is that correct? Thanks!

2

The lighting is not slower, but deferred rendering has a large upfront hit due to the totally different way of handling, at the benefit that it scales worlds better if you add up more and more lights as deferred is all about pixels rendered on screen, while forward rendering is about objects that were hit by light and realtime shadows.

as for the PS: thats expected, gpu drivers don’t support AA for deferred so yeah thats correct, you can use the edge blur or develop an own more complex post fx AA solution

3

If you have lots of point and spot lights, then deferred rendering is faster. Otherwise, not. Also, image effects can be cheaper with deferred rendering.

–Eric