AuraLite Shaders

🚀 What's New in v1.1.4 — Atmosphere LUTs, Distant Horizons Seam Fix & Half-Res Bloom

Version 1.1.4 rebuilds the experimental physical sky around shared low-frequency LUTs, replaces the hole-producing DH screen-door seam with a deterministic hand-off, and cuts post-process cost with skippable half-resolution bloom. It also finishes the TAA story for Distant Horizons (correct DH reprojection + Halton jitter on LOD geometry) and swaps glittery water fBm for a coherent Gerstner swell.

🧪 Shared Physical-Atmosphere LUTs (begin / begin1)

• Tiny HDR LUTs, not fullscreen buffers. v1.1.3 deleted unused full-screen colortex5/colortex6 to save VRAM. v1.1.4 brings them back as 64×32 solar-transmittance (colortex5) and 32×16 multi-scatter / ground-bounce (colortex6) tables — kilobytes, not megabytes.
• begin.fsh rebuilds direct solar transmittance every frame: sun elevation on X (−0.16…1.0, including civil twilight), camera altitude on Y (0–30 km), Kasten–Young airmass × Rayleigh + aerosol extinction, zeroed below the night hemisphere.
• begin1.fsh layers bounded multi-scattering and biome-aware ground bounce on top of that transmittance. Noon is Rayleigh-blue; low sun is warm; swamp/snow/vegetation tints come from GROUND_BOUNCE_MODE.
• Shared by every physical-sky consumer — gbuffers_skybasic, terrain fog, water analytic reflection, volumetric godrays, clouds and the SSR sky fallback all sample the same LUTs instead of each running a second atmosphere march.
• When SKY_MODE=0 (every shipped profile) the LUT passes write constants and cost almost nothing. Enable Physical Sky manually in the Experimental tab.

New Experimental → Atmosphere options (off-profile defaults stay cinematic / auto):

• ATMOSPHERE_TURBIDITY — Crisp / Balanced / Hazy aerosol load.
• ATMOSPHERE_SCALE — Compact 25 m / Balanced 50 m / Cinematic 100 m per block (how Minecraft Y maps into atmosphere kilometres).
• GROUND_BOUNCE_MODE — Auto (biome-aware) / Neutral Soil / Vegetation / Snow / Desert.
• SKY_TEMPORAL — rotation-only history blend for the sky (requires TAA). Physical sky uses a higher history weight than the animated gradient sky so stars/aurora do not trail.

The swamp detector now also matches BIOME_MANGROVE_SWAMP.

🌍 Distant Horizons — Hard Seam, TAA & Iris Workaround

⚠️ AuraLite still does NOT claim full Distant Horizons compatibility. v1.1.4 is a targeted correctness pass on the v1.1.2/v1.1.3 experimental path.

• Hard deterministic hand-off at far. The v1.1.3 16 m screen-door dither discarded random LOD fragments in the seam band; on DH 3.2 those holes showed sky/white whenever vanilla geometry did not fill the same pixel. DH fragments with dist < far are now simply discarded — less cinematic, never stochastic.
• DH receives the same optional Halton camera jitter as vanilla gbuffers. composite1.fsh reprojects DH pixels through dhProjectionInverse + dhPreviousProjection (vanilla matrices have the wrong far plane).
• Conservative DH history cap (0.45) — LOD meshes change topology as chunks stream; they participate in TAA but cannot leave long trails.
• DH_BLOCK_ILLUMINATED tag colortex2.a = 0.24 — distant sea lanterns / glowstone stay self-emissive even when they are not lava-orange or portal-violet. Extra DH material classes: DIRT, SAND, TERRACOTTA.
• dh_water now honours WATER_WAVES / riffles / transparency / specular, applies the frozen-ocean navy floor, and occludes against dhDepthTex1 (plus Iris depthtex1 via view-space Z, because raw depths use different projections).
• DH_SHADOW_RANGE — Seam (1.25×) / Extended (2×) / Far (4×) of vanilla far. LOD receivers can keep sampling the shared shadow map past the vanilla chunk edge.
• Shadow-map footprint rebalanced for DH: MED 192 m, HIGH/ULTRA 512 m, EXTREME 768 m (VERY_LOW/LOW stay 60 m, no shadows).
• dhShadow.enabled=false by default. DH 3.2.0-b + Iris 1.7.6 can replace/cull the vanilla terrain shadow pass — symptom: mob shadows remain, block shadows vanish even in vanilla chunks. Users with a verified working Iris/DH bridge can turn the DH shadow pass back on and then use DH_SHADOW_RANGE.

🎯 TAA — Sky Temporal Resolve & Material Reactive Mask

• Sky temporal resolve (SKY_TEMPORAL) — sky pixels have no stable world position, so history is reprojected with camera rotation only (no translation). Gradient-sky history weight is lower (0.28) than Physical (0.46) so clouds/aurora/meteors do not smear.
• Material reactive mask — water (0.8), foliage (0.62) and emissive/lava (< 0.5) cut history weight by 46% / 30% / 58%. Without a per-object velocity buffer this is what stops waving leaves and water from ghosting after TAA.

🌊 Gerstner Water Spectrum

• Replaces the v1.1.3 value-noise / fBm central-difference normal in final.fsh. That field was mathematically stable but read as high-frequency random glitter.
• A 4-direction travelling swell (dominant wind + cross swell + two low-amplitude ripples) produces analytic slopes and a calmer default surface. Amplitude is clamped to ±0.22.
• Near-water vertex swell is slightly reduced (0.04/0.02 → 0.032/0.016) so the geometric mesh matches the new reflection spectrum.
• Dead Voronoi lava-height helpers removed from gbuffers_water, gbuffers_terrain_translucent and gbuffers_terrain (lava stays texture-driven).

✨ Half-Resolution, Skippable HDR Bloom

• New master BLOOM toggle. VERY_LOW / LOW skip the entire 5-pass chain via program.composite3–7.enabled=BLOOM (Iris/OptiFine do not even dispatch the programs).
• colortex3/colortex4 are half-resolution (size.buffer = 0.5 0.5). Gaussian strides are doubled so the world-space radius stays the same; final.fsh linearly upsamples the glow.
• TAA similarly gates composite1/composite2, so lighter profiles no longer pay for unused fullscreen passes.

🌌 Aurora Quality

• New AURORA_QUALITY — Soft 8 / Balanced 12 / Silky 18 raymarch steps, with a centred globally-animated ray start (the previous per-pixel hash grain is gone).

🎚️ Profile Rebalance (v1.1.4)

Camera jitter remains off by default in every profile.