Generate and use shadow maps separately - is it possible?

Hi All,

I have a two player game and want to have live shadows for the two player characters. But the spotlight needs to be fairly wide to cover the play ‘arena’ and I’m therefore losing a lot of render resolution. I have to set it to at least 1024 pixels not to get to ugly pixel crawling.

So instead I wanted to have two ‘dummy shadow casting spotlights/Blueprints’ that could feed their shadow maps to the main ‘hero’ spotlight to use in the rendering.
Because then I could get away with maybe 256 pixels or at least 512. This would save me half the shadow render time at the very least and much more if I could use 256.
Shadow depths + projection is taking about 1.5ms which is a lot for me since I’m doing vr and targeting 11ms frames.
It seems like the shadow *projection *is taking the most time but I thought this would be worth trying if it was possible?

I have used systems like that in VFX (ie offline) but I see no reason why that wouldn’t work in realitime too. But of course I’m not sure about how big overheads might be.

Also I was wondering if anyone knew a way that I could see the shadow maps as an picture? So I could debug my shadowing actors and make sure I only render what I need for shadows.

Cheers