Hi everyone,
I would like to ask if there’s a way to bake using GPU Lightmass but also keep the interaction of light and volumetric fog?
Ray-traced viewport:
Baked result:
Any help is highly appreciated!
Thank you in advance!
Hi everyone,
I would like to ask if there’s a way to bake using GPU Lightmass but also keep the interaction of light and volumetric fog?
Ray-traced viewport:
Baked result:
Any help is highly appreciated!
Thank you in advance!
yes. but… undoubtfully cpu lightmass does a better job integrating volumetric light and shadows, if you require them.
gpu does a crosswired intersection with the shadows and the fogvolume.
you can move the volumes out of the way for the bake and put them back later. you will not get the same volumetric shadows, tho.
Thank you for the response, glitchered!
I understand what you wrote, I think, but I just lose all volumetric fog interactions after I bake. I am using an Exponential Height Fog component with Volumetric Fog ticked.
The interactions stay on Movable lights, but not on Static, baked ones.
What am I missing here?
you’re not using a fog volume? okay. then you’re limited to the lightmap volume itself, that gotta do the trick. the volumetric lightmaps have a resolution, tho. the default is 2 meters per “light voxel”. you gotta be smart where you place the light.
it should be off center or it will cast light directly into the voxel center. if you need more resolution you can crank up the volume detail size. be aware baking time gonna inrease a lil and more data is generated.
i hope you get the gist of it.
Are you using a Lightmass Character Indirect Detail Volume ? It should help with the volumetric lightmap resolution.
You’ll either need to fake the fog scattering effect, or use a stationary light.
@ZacD nope. this is not indirect lighting. this is casting static baked volume lighting into a heightfog volume or local fog volume.
i got something to scale out of it at half a meter volume resolution.
i personally would add a local fog volume with a noize function to spice it up. scatter fake. sharp shadows looks kinda dated to me. just me opinion.
if you want that sharp stuff… the static volume lighting will not get you there. there are techniques to fake it kinda cheap. like putting light cones with a gradient texture there.
or you just use stationary or movable lamps to get the sharp shadows. the performance hit is kinda neglectable, unless you deal with mobile platform and rendering limitations.
Just my opinion but I really don’t think increasing the volumetric lightmap resolution is a good way to approach this, it greatly increases the memory cost of the VLM for minimal benefit.
Additionally, if performance is so much of a concern that you aren’t even willing to use a movable/stationary light, then you should probably not be using volumetric fog either… Camera facing cards have been used for light scattering for decades with good results, even by todays standards.
agreed. for this kinda scenario with the sharp shadows it certainly is not the right choice. i had fun experimenting with it tho. it’s neat to push ambient lit fogging if one’s in baked lighting game. for xtreme details it’s no good. yep