hillsguy.bsky.social

hello I try to develop video games (sometimes)😊
also

[hillsguy.bsky.social @Hillsguy2]

Decided to check out how water is rendered in Counter-Strike 2
Given how interactive water in CS2 is, I expected to see some cell fluid simulation, but turns out they use just a low-res off-screen buffer with flat 2D decals for various water effects. Reminds me of HL2 water :)

[hillsguy.bsky.social @Hillsguy2]

@Linkz01 This doesn't make sense for regular color images, but for textures, where each channel is a separate data source (see channel packing, PBR ARM/ORM maps) this can result in higher perceptual quality.

[hillsguy.bsky.social @Hillsguy2]

Experimenting with S3TC/BC1/DXT1 compression. The idea is to intentionally leak channel data into each other to reduce blockiness and get at least some data instead of averaged out 4x4 blocks.

[hillsguy.bsky.social @Hillsguy2]

@Linkz01 The end result is that data from channels parallel to endpoints direction ends up in channels that are perpendicular to this direction. This is where leaking comes from.

[hillsguy.bsky.social @Hillsguy2]

@Triste_Hispania The difference is most noticeable on the blue channel.

[hillsguy.bsky.social @Hillsguy2]

raytraced reference vs normal map + bent normals and ao for self-shadowing + separate bent normals and ao texture for light bounce 🫠

[hillsguy.bsky.social @Hillsguy2]

Still looks videogame-y to my taste but better than regular normal maps...

[hillsguy.bsky.social @Hillsguy2]

Came up with a cursed workaround for baking bent normals purely in Blender 3D using the raycast shader node. Bent normals are usually used for self-shadowing and reflection occlusion.

1. Regular normal map
2. Normal map + raytraced shadows
3. Normal map + bent normal map
#b3d

[hillsguy.bsky.social @Hillsguy2]

This is how visibility data looks like at the pixel level.
1. Raytraced visibility
2. Visibility approximated using bent normals

[hillsguy.bsky.social @Hillsguy2]

Found a nice way to visualize and debug directional lighting data
Again, raytraced reference vs per-channel RGB AHD lightmap

[hillsguy.bsky.social @Hillsguy2]

@ArtOfPilgrim https://t.co/Zzs6G2k42q

[hillsguy.bsky.social @Hillsguy2]

@SebAaltonen @ankkala @JCeacc Why not? Is precomputing visibility going to be too long or is it too slow to query precomputed visibility data for complex scenes?

[hillsguy.bsky.social @Hillsguy2]

Silent Hill 2

[hillsguy.bsky.social @Hillsguy2]

@guycalledfrank https://t.co/vMIlg9P7ZS

[hillsguy.bsky.social @Hillsguy2]

Collecting references 🫠

[hillsguy.bsky.social @Hillsguy2]

@guycalledfrank Theoretically SH should work better for smooth GI while AHD should work better for direct light sources, but I can't notice any meaningful difference in my implementation at the moment.

[hillsguy.bsky.social @Hillsguy2]

Ray-traced reference vs spherical harmonics (L0+L1) 1024x lightmap vs per-channel AHD (dominant direction) irradz 1024x lightmap
I can barely see any difference...

[hillsguy.bsky.social @Hillsguy2]

@guycalledfrank For me AHD and SH seem pretty close mathematically and conceptually, the only difference is how you store light data and how light is applied (smooth gradient over hemisphere vs dot product or some other diffuse bsdf). So I don't think that AHD should be inherently worse than SH.

[hillsguy.bsky.social @Hillsguy2]

@guycalledfrank reference vs sh vs rgb ahd 🤔

[hillsguy.bsky.social @Hillsguy2]

@senorDane Dominant direction lightmaps usually consist of ambient color, highlight color and highlight direction, so there's ambient color for non dominant directions. See https://t.co/J57kHAudSR