in hindsight this makes sense. occluders should be small, since they set up the depth buffer, but then occlusion culling can be done on whole chunks since it doesn't matter how big the area you're testing at one time is so long as the occlusion map is filled up properly

so next i might try rendering single blocks into the occlusion map and depth culling entire chunks always and see how that performs

16 visible chunk radius now runs at 68 fps above ground (1 short of being truly nice 😔) and the occlusion culler runs in only 5ms

simplified everything and split occluders from depth culling candidate chunks

also trying to be more picky and granular about what occluders to use, so now i'm rendering single blocks nearby the camera. hopefully more granular occluders will improve the culling percentage

you can call me weird but it is very fun to build a little box around myself and watch my fps go up from 110 to 450 because of the depth occlusion system

hmm hmm so my subchunk levels go 1³, 2³, 4³, 8³, 16³

but im betting anything above 2³ is gonna be exceedingly rare since a new requirement is having a block with an exposed face. though i havent tested this

but i feel like maybe 1³, then 2²x1 4²x1 8²x1 16²x1 for each axis would probably work a *lot* better given how human construction tends to go

and also ground planes/cliff faces

i'm *sure* you'll all find this as riveting as i do, but while there are loads of 8x8x8 areas of fully opaque blocks with at least one visible exterior face, there appear to be literally no 16x16x16 areas of the same description in any given chunk >_>

here's photographic evidence of all the 8x8x8 blobs out in their natural habitat

so i've tweaked all the parameters and above ground its now culling 75% ish of chunks that survive frustum culling. even at 24 chunk radius it runs in ~8ms so about half a frame (and it's threaded so that's fine)

and i'm getting 75 fps above ground at 16 render dist, and 115 at 12. and indoors or in caves its more like 300-400

so i'd call this feature a success and also done for the time being!

being in a cave make fps go zoom! :3

(lol the alt badge hides the fps counter. it reads 450)

ngl this never gets old (turning occlusion culling on and off to show how much its culling)