AuraLite Shaders

🚀 What's New in v1.1.2 — Render-Distance Shadows & Experimental Distant Horizons (Partial)

Version 1.1.2 extends shadow rendering to the actual render distance with an adaptive LOD system, fixes HDR/TAA pipeline strictness, cleans up deprecated GLSL, and introduces partial, experimental Distant Horizons support (WIP) — without claiming full compatibility yet. Work is ongoing.

🌗 Extended Shadow Distance with Adaptive LOD

• Shadows now reach render distance. shadowDistance was 60-160m with a hard cutoff at shadowDistance. Now it scales with quality profiles: 60m (VERY_LOW/LOW, no shadows) → 120m (MED) → 256m (HIGH/ULTRA) → 384m (EXTREME). The cutoff is replaced by a soft fade smoothstep(far*0.85, far*0.98).
• New SHADOW_LOD toggle — Off / Balanced / Aggressive. Reduces sample count and expands filter radius at distance to keep performance stable:
  • Balanced: >25% far → 16 samples ×1.8 radius, >50% → 8 ×2.8
  • Aggressive: >15% → 16×2.0, >35% → 8×3.5, >60% → 4×5.0
  • Beyond 95% far shadow sampling is skipped entirely.
• shadowMapResolution now includes 8192. EXTREME uses 8192 for maximum texel density at 384m. HIGH stays 2048, ULTRA 4096.
• New SHADOW_PCSS_BLUR toggle — fixed softness vs PCSS penumbra softening. When enabled, penumbra grows with blocker distance and rain. When disabled, shadows use constant softness.
• PCSS correctness fixes in composite.fsh:sampleShadow(): added UV bounds checks (prevents clamp-to-border artifacts), avgBlockerDepth clamped to 1e-4 to avoid NaN, penumbraSize clamped 0-2.0, lightSize reduced 140→40 to prevent light bleeding, actualSpread capped to 16.0, out-of-bounds samples counted as unshadowed (1.0) for correct averaging.
• Shadow bias distBias now scales with far instead of shadowDistance, plus extra water receiver bias for tagged water pixels (colortex2.a≈0.8).

🔧 HDR Pipeline Strictness Fix

• Dummy #define RGBA16F 0 guards added before the const int colortex*Format = RGBA16F directives. This satisfies strict GLSL validators (C1503 undefined variable RGBA16F) while Iris/OptiFine's parser still reads the format names (spec second clause). In v1.1.1 the directives were inside a /* */ comment and were ignored by some loaders.
• Now all used buffers are explicitly RGBA16F: colortex0/1/2 (main HDR + PBR + material tags), colortex3/4/5/6 (unused today but set to HDR for a full pipeline), colortex7 (TAA history, colortex7Clear=false), and optional shadowcolor0/1Format = RGBA16F.
• Cost noted: ~16MB per 1080p RGBA16F buffer → ~128MB VRAM for 8 buffers.

🌍 Experimental — Partial Distant Horizons Support (WIP, not full support)

⚠️ AuraLite does NOT yet claim full Distant Horizons compatibility. v1.1.2 only adds a minimal, experimental code path so LOD chunks are no longer invisible under Iris. It's functional enough for testing, but considered partial and work-in-progress.

• Why it was needed: Without dh_terrain.vsh/.fsh, dh_water.vsh/.fsh, dh_shadow.vsh/.fsh, Iris marks the pack as incompatible with DH and simply doesn't draw DH's simplified LOD chunks at all — symptom "shader works but DH chunks invisible". Presence of these files is enough for Iris/DH auto-detection (dhShadow.enabled defaults true).
• What v1.1.2 does:
  • dh_terrain/dh_water write the same colortex0/1/2 layout as vanilla passes, so existing lighting/fog/shadow/cloud/godray code in composite.fsh applies to LOD geometry without other changes.
  • Depth reconciliation in composite.fsh: detects depthtex0>=1.0 && dhDepthTex0<1.0 → isDHTerrain, reconstructs viewPos via dhProjectionInverse (not gbufferProjectionInverse — different far planes) and computes isSkyPixel. Fixes DH terrain being treated as sky (flat/washed-out).
  • Fog rescale: effectiveDensity *= far/dhRenderDistance prevents exponential fog from saturating to white before DH draw distance.
  • Emissive fast-path uses !isSkyPixel instead of depth<1.0 so distant DH_BLOCK_ILLUMINATED (glowstone/lanterns) is still emissive.
  • final.fsh heat shimmer now checks dhDepthTex0 via isRealGeometry so distant lava lakes also shimmer.
  • Overdraw prevention: if(dist < far+16.0) discard in DH passes — DH renders entire world including area already covered by vanilla chunks; without discard both fight over same G-buffer pixel causing Z-fighting / missing water/ice.
• Current limitations (why it's partial):
  • gl_MultiTexCoord2 is not guaranteed to carry valid lightmap data for DH programs — v1.1.2 hardcodes lmcoord = vec2(0.0,1.0) (open sky, no torch). Correct for exterior DH, but not interior-perfect.
  • No LabPBR normals/specular maps for DH — roughness/metalness approximated per dhMaterialId (STONE/WOOD/METAL/SNOW/LEAVES/LAVA...). No POM on DH.
  • Water uses flat vertex normal, not procedurally displaced like near water.
  • Fog/sky/cloud code paths are shared but DH has coarser geometry.
• Ongoing work: proper skylight baking if DH ever exposes it, LabPBR fallback, smoother transition seam, performance tuning. Full support will be announced separately.

🛠️ Pipeline Cleanup & Fixes

• Menu split fix — [v1.1.1-ui-hotfix]: Oversized option screens were split into [SHADOW_OPTIONS], [PBR_OPTIONS], [AO_REFLECTIONS], [CLOUD_SHAPE], [LIGHT_SHAFTS], [NIGHT_SKY] because some Iris/OptiFine UI builds silently hide buttons when a screen has too many entries.
• Deprecated ftransform() removed from composite.vsh, final.vsh, gbuffers_clouds.vsh, composite1.vsh, composite2.vsh, gbuffers_weather.vsh — replaced with explicit gl_ProjectionMatrix * gl_ModelViewMatrix * gl_Vertex for broader driver compat (same fix applied to shadow.vsh in v1.1.0).
• Final pass cleanup: Removed two duplicate copy-pasted post-gamma dither blocks that contradicted the comment about linear-space dither (triangle ±1/255 before tonemap). The single pre-tonemap dither remains — more effective in darks, silent in brights.
• Bias & stale comment fixes: Corrected stale colortex6 hand-off comment (removed in v1.0.3), now notes that final.fsh reads normal from colortex2 and roughness from colortex1.z.
• Rebalanced profiles to reflect new distances and LOD:
  • VERY_LOW/LOW 60m (no shadows), MED 120m Balanced, HIGH 256m Balanced, ULTRA 256m Aggressive, EXTREME 384m Aggressive + 8192 res.
• Localization: Bumped lang/*.lang headers v1.0.7 → v1.1.2, translated previously-English profile.*.comment placeholders into native languages (ur_pk, vi_vn, zh_cn, zh_hk, zh_tw and others).