AuraLite Shaders

🚀 What's New in v1.1.3 — True TAA, HDR Bloom Pyramid & Black-Water Regression Fix

Version 1.1.3 completes the TAA pipeline (Halton sub-pixel camera jitter + YCoCg variance clipping), replaces the old single-pass bloom with a true multi-octave HDR gaussian pyramid, and fixes the long-standing black-water regression with MRT-proof water detection. It also adds procedural raindrop rings, biome-aware murky swamp water, underwater plant sway, post-TAA sharpening, and a ~48 MB VRAM cleanup.

🎯 True Temporal Anti-Aliasing (Halton Jitter + YCoCg Clipping)

• Halton(2,3) sub-pixel camera jitter — every gbuffer vertex shader can offset gl_Position by a rotating 8-frame Halton pattern (±0.5 px). Previously TAA only blended history without jittering the sample point, so it could only blur noise instead of reconstructing sub-pixel detail.
• TAA_JITTER option — Off / Subtle / Standard / Strong (new in v1.1.3). The jitter is OFF by default in all profiles for a rock-steady image; Subtle (±0.25 px), Standard (±0.5 px) and Strong (±0.75 px) scale the amplitude for users who want the full sub-pixel reconstruction (removes high-frequency shimmer at the cost of a slight temporal wobble). Requires TAA enabled.
• Previous-frame jitter compensation in composite1.fsh — the old frame's offset is re-added to the reprojection (with the same strength scale), so static images converge instead of smearing ~0.5 px. Only active while jitter is on.
• YCoCg variance clipping (μ ± γσ) replaces the axis-aligned 3×3 min/max box — the old box caused ghost trails on saturated high-contrast edges (fences, wires, hot specular) while being too tight on flat gradients. Clip width scales with TAA_STRENGTH: 1.50 Light / 1.25 Balanced / 1.10 Stable.
• Frame-rotated IGN dithers now resolve cleanly — godrays and volumetric clouds rotate their interleaved-gradient-noise patterns per frame; with the temporal resolve they integrate into smooth gradients instead of shimmering.
• TAA is on by default in HIGH / ULTRA / EXTREME profiles (off on VERY_LOW / LOW / MED for maximum FPS); it can be toggled in the Post-Processing menu, and TAA_STRENGTH presets the variance-clip tightness.

✨ HDR Gaussian-Pyramid Bloom (composite3 – composite7)

• Replaces the v1.0.1 single-pass 3×3 neighbour glow, whose ~1.5 px radius could only produce a tight halo.
• New 5-pass chain: threshold brightpass (0.75 luma soft-knee, exposure-aware) → tight separable gaussian (9-tap, σ≈2.0) → wide separable gaussian (4× stride). Successive blurs compose to an effective σ ≈ 8.2 px — a soft cinematic falloff around the sun/moon disks, lava, portals and hot specular, without a mip chain.
• Runs after the TAA resolve, so the bloom energy is temporally stable.
• New HDR_BLOOM option (Subtle 0.06 / Balanced 0.12 / Strong 0.22 amplitude) wired into every quality profile.

💧 Black-Water Regression Fix — MRT-Proof Water Detection

• Root cause: on some Iris builds the translucent pass drops the colortex1/colortex2 MRT writes entirely — water then arrives with a zeroed normal + alpha + lightmap. The emissive fast-path (alpha < 0.5) swallowed it and every tag/lightmap-based system died with it.
• Detection ladder: primary = colortex2.a = 0.8 tag; rescue = the depth difference (depthtex1 solid-only vs depthtex0) proves a translucent surface on top, then a hue-fingerprint classifier on the albedo rejects portals (violet, green-starved) and lava (blue-starved) while accepting water (blue/blue-green, never pale). Water, ice and glass classify; torch flames, portal sparkles, squid ink, pale ice and clear glass do not.
• Synthesized flat water normal when the decoded normal is untrustworthy (MRT loss or clear value), so Fresnel/reflections still have sane inputs.
• Analytic sky reflection (waterSkyRefl) — zenith/horizon gradient + warm sun-side glow, dimension-aware (Overworld palette, Nether biome sheen, End violet sheen), applied via Schlick Fresnel with a 0.20 floor (pure F0≈0.02 at steep look-down angles was exactly what let shadowed water crush to black), multiplied by skyLight so cave water stays dark. This is the actual black-water fix and works with SSR disabled.
• Diffuse ambient floor for rescued pixels whose lightmap may read zero.
• Navy-tint floor in gbuffers_water/gbuffers_terrain_translucent — frozen-ocean biome tints (e.g. 0x3938C9) can no longer crush R/G to black after the gamma pipeline.
• WATER_DEBUG diagnostics overlay (Off / Classify / Lightmap / Raw tag alpha) — green = healthy tag, red = depth-rescued, yellow = rescued from the emissive path, magenta = lava/portal-guarded.

🪟 SSR & Refraction Fixes (final.fsh)

• Procedural sky fallback for reflection rays that leave the screen or hit the sky — previously black (the reason the waterMirrorBoost hack existed); now a day/night/sunset/storm-aware gradient with moon-phase brightness, Schlick-Fresnel weighting and edge fade.
• SSR march start moved 1.0 → 0.5 view units off the surface so the water plane at the player's feet still reflects near-field geometry.
• MRT-proof water detection reused for SSR/refraction (same hue guards as composite.fsh).
• Procedural raindrop rings on wet up-facing surfaces — two layers of expanding, world-stable circular waves perturb the SSR normal so rain reads as thousands of tiny ripples instead of one flat mirror.

🔍 Post-TAA Sharpening (POST_SHARPEN)

• Gentle 5-tap unsharp mask (0.18 amplitude, clamped ≥ 0) applied to the resolved image before refraction/SSR/bloom work, recovering texture detail softened by TAA's history blending. On in MED+ profiles.

☁️ Volumetric Clouds — Quality Scaling & Dithered Ray Start

• New CLOUD_QUALITY option: 8 / 12 / 16 raymarch steps (was hardcoded 12) — Cheap / Standard / High.
• Dithered ray start (frame-rotated IGN) on geometry pixels when TAA is enabled: the frame-rotating pattern is temporally resolved into a smooth volumetric integral, killing the 12-step ribbing on thick cumulus without the v0.2.5-era "swimming". Sky pixels keep the stable centred start.

🌿 Underwater Plants Sway

• New block class 10010 (seagrass, tall_seagrass, kelp, kelp_plant, sea_pickle) — fronds sway in a current, phase-shifted by height so the tips lag the base, storm-agitated along with the surface foliage path. Displacement is mirrored in shadow.vsh so shadows follow the visible fronds.

🌊 Biome-Aware Murky Water

• Smoothed swamp/mangrove detector (isSwampBiome) — swamp water absorbs more red and reads greener and murkier (absorption (0.23, 0.038, 0.10), deep colour pushed to dark green) instead of open-ocean blue.

🧪 Physical Sky — Warm Ground Bounce

• The experimental SKY_MODE=1 atmosphere now includes a warm ground-bounce term: terrain's ~15–20% mean albedo re-scatters in the lower atmosphere (strongest at the horizon and with a high sun), removing the "sterile" blue-bias horizon band.

🌇 Lighting & Ambience

• Rayleigh-tinted day ambient — the day hemisphere ambient now follows the actual sun extinction: golden-hour light is warm and blue-depleted instead of static grey-blue.
• Held-light temperature — strong held sources (sea lantern, glowstone, shroomlight, lava bucket) read slightly cooler than candle-strength light.

🌍 Distant Horizons — Soft Seam

• The v1.1.2 hard discard at far + 16 is replaced by a screen-door dithered transition band: DH LOD fragments stochastically blend into vanilla chunks over 16 m, so crossing the boundary or changing render distance no longer shows a hard cut. The pattern is static per frame (DH-only pixels are excluded from TAA history).

🛠️ Pipeline & VRAM Cleanup

• Removed colortex5/colortex6 format directives — never read or written, but each forced Iris/OptiFine to allocate a full RGBA16F screen buffer: ~32 MB saved @1080p, ~128 MB @4K.
• shadowcolor0Format RGBA16F → RGBA8 (it only carries LDR tex * glcolor): another ~16 MB @1080p / ~64 MB @4K.
• shadowcolor1Format removed (nothing ever wrote to it).
• colortex0Clear = true — no stale garbage on the first frame or after a window resize.
• colortex3/colortex4 are now actually used by the bloom pyramid; the full 8-buffer HDR pipeline is engaged.