## v3 ### Blocky cloud styling * Blocky clouds form smaller connected clusters with raised edges and taller centres. Bases have deeper shading, sun-facing sides are brighter, and backlit edges catch a restrained highlight. * The voxel grid drifts with the cloud shape instead of changing occupancy on a fixed world grid. Cloud shadows and reflection density follow it. * Shape sampling uses two noise octaves per column instead of three, with the existing traversal and self-shadow sample budgets. ### Water and camera corrections * Water uses gentler wave packets with varying crest strength and direction. * Confirmed water reflection hits keep their scene colour. Visible blockers suppress sky fallback, including when detailed reflections are disabled. Waterfalls use ambient fallback rather than detailed sky reflections. * Underwater sky directions refract through the surface. Underwater View Radius now defaults to 1.0 for the physical critical angle. * Sun and moon directions remove Iris's camera translation. Glare visibility uses world shadows and cloud density with shadows enabled, and its strength no longer uses viewport distance from the light. ### Quality and performance fixes * Texture colours and vertex tints are decoded before lighting, and the final image is display encoded. FXAA and sharpening now run after bloom and tone mapping. * Iris loads baked atmosphere transmittance and multiple-scattering tables. OptiFine keeps the integration fallback. Sky transmission no longer repeats the sunlight and scattering calculations used for sky radiance. * Parallax respects texture sprite bounds and retains the original texture gradients. It is off in every profile. * Ambient occlusion now removes ambient light before water and glass are drawn. It preserves direct light and emission, and uses four depth-aware samples to reconstruct the half-resolution result. * DH Screen Shadows have explicit Off, Balanced, and High settings. Potato, Low, and Medium leave them off. High uses 8 ray steps and Ultra uses 24. * Entity diffuse and specular lighting share one shadow lookup. Volumetric light stops at visible DH terrain when native depth contains sky. * Block cloud hit distances include the distance from the camera to the cloud layer. View, shadow, and reflection paths share the block cloud field. * Underwater reflections use dielectric Fresnel and total internal reflection at the water critical angle, including the actual angle of side faces. * Coloured block light uses one filtered volume sample instead of eight. Shadow blocker samples now include the centre and interior of the search disk at the existing sample budget. * Target GPU frame times and in-game images remain unmeasured. ### Physically based atmosphere * The Overworld sky, sunlight, moonlight, ambient light, and fog now come from one atmosphere model. It uses Earth's published Rayleigh, aerosol, and ozone coefficients from Bruneton (2017) and Hillaire (2020). Four prepare passes fill a 256 x 288 buffer. Iris copies the baked transmittance and multiple-scattering tables, then updates the sky-view table and light colours each frame. OptiFine integrates all tables each frame. * Sunlight passes through the atmosphere, so it warms and dims as the sun lowers. Sun and moon light both reach zero at the horizon, which removes the shadow jump when Iris switches the shadow light at sunrise and sunset. * Ambient light is the integrated sky plus ground bounce. Sky luminance is normalized to the CIE clear-sky zenith at Linke turbidity 3.5, and clear-noon daylight is the white point. * A square-root adaptation to daylight keeps golden hour, sunset, and twilight readable. It scales sun, moon, and sky light only. Block light is unchanged. * Stars, the moon, and the sun disc dim and redden toward the horizon. ### Distant Horizons and fog * Native and DH terrain use one fog law. The DH-only density cut and the far distance scaling are gone. They changed the fog gradient near the native render edge. * Terrain fades toward the sky's own scattered light, so distant land meets the sky at the horizon without a colour seam. Distant hills pick up blue haze. * Clouds and cirrus receive the same haze based on their distance. * The DH edge fade covers the last 28% of the LOD range instead of the last 7.5%. * Ground mist keeps its sea-level pooling and its dawn, night, and weather changes at a lower clear-day density. ### Volumetric light * With Volumetric Light on, light shafts come from the shadow map. Each half-resolution pixel marches its view ray through height-based haze and tests the shadow map at every step. Trees, cave mouths, and windows cast beams from any viewing angle, not only when the sun is on screen. * Scattering uses a Henyey-Greenstein forward lobe mixed with an isotropic term, so beams are strongest toward the sun or moon. The haze thickens at dawn, in rain, and on hazy days. * Settings: Volumetric Light, Volumetric Light Quality, and Volumetric Fog Density. Light Shaft Strength still scales the result. The screen-space shafts remain when Volumetric Light is off. ### Ground-truth ambient occlusion * Ambient occlusion uses ground-truth ambient occlusion (GTAO), after Jimenez and others (2016). It searches the depth buffer for horizons along two to four directions and integrates cosine-weighted visibility. Normals come from the depth buffer. * Each direction is compared with its own unoccluded value, so flat ground and convex edges stay unshaded and only real creases darken. * The pass runs at half resolution and rebuilds every position from the centre of the full-resolution depth texel it read. Samples that lie within a few degrees of the surface plane cannot occlude it. The first version mixed half-pixel offsets into the depth reconstruction and drew vertical stripes on walls seen at a steep angle. * Occlusion reads `depthtex2`, which has no hand or translucent blocks, and skips pixels where the hand is in front. It runs before water and glass are drawn, so their depth cannot occlude the scene behind them. * The half-resolution result uses four depth-aware bilinear samples. Native and DH samples use their own projection and do not blend across each other. * Settings: Ambient Occlusion Quality chooses 2, 3, or 4 directions with 4, 6, or 8 samples each. Distant Horizons terrain keeps the previous estimate. ### Daily weather * Each Minecraft day has its own cloud cover, haze, and cirrus amount. Cloud cover shifts by up to 0.14, haze ranges from half to double, and cirrus from none to double. The next day's weather fades in between 16000 and 20000 ticks, around midnight. * Clouds, cloud shadows, cloud reflections, fog, and volumetric light all read the same daily values. * Settings: Daily Weather and Daily Weather Variety. ### Settings and profiles * The menu has new Lighting, Fog & Light Shafts, World Effects, and Camera pages in place of the old Visuals page. * A Potato profile turns off the shadow pass and every expensive effect. * Every profile now sets the same 32 performance options. The defaults match Medium, so a new install shows Medium instead of Custom. * Use Brightness Slider: Minecraft's Brightness setting above the middle now lifts caves and nights. The middle setting and below look as before. * Cloud Smoothing is visible in the menu. The Shadows toggle now also skips the shadow pass when coloured block light is off. ### OptiFine * Experimental OptiFine fallbacks, not yet tested in game. OptiFine has no `hasSkylight` uniform, so the pack maps it to a custom uniform that is always true. Shadows fall back to `cameraPosition` for texel alignment when Iris's integer camera uniforms are missing. * Distant Horizons and coloured block light remain Iris only. ### Coloured block light * Light sources tint the blocks around them with their own colour. Soul fire and soul lanterns glow cyan, redstone glows red, and sea lanterns, froglights, amethyst, and crying obsidian keep their own hues. Nearby lights of different colours mix. * The colour comes from each light source's own texture, so resource packs change it. Light sources are the blocks listed in `block.properties`. Torches, lanterns, fire, and campfires keep the warm torch colour, and their soul versions turn cyan. * Stained glass tints light that passes through it, and walls stop light of one colour from reaching the room next door. * Brightness still follows the vanilla light level, so rooms are exactly as bright as before. Only the hue changes. * The shadow pass writes light sources, walls, and glass into a voxel volume around the player. A compute pass spreads the colour one block per frame. The volume follows the camera without shifting the colours. * Settings: Colored Block Light, Colored Light Range of 64, 128, or 192 blocks, and Colored Light Saturation. It is off by default until it has been confirmed in game. Iris versions without custom images fall back to the torch colour. * Torches, lanterns, and their soul versions moved to block ID 10015, and amethyst clusters and buds to 10016. They keep their emissive glow. * The shadow pass uses `#version 400 compatibility` with `GL_ARB_shader_image_load_store` and reads `at_midBlock` as `vec3`, the setup Photon uses on Iris. The first version used `#version 430` and a `vec4` `at_midBlock` and corrupted terrain geometry in game. ### Option fixes * Shadows, Light Shafts, Rain Puddles, Portal Glow, Heat Shimmer, Cloud Smoothing, Volumetric Light, and Colored Block Light could not be toggled. Iris only registers a boolean option that some shader checks with a plain `#ifdef` or `#ifndef`. These options were only checked inside `#if defined(...)`, so Iris ignored them, kept them on, and skipped them in profiles. Each now has a plain `#ifdef` check. The first five were already affected in v2. ### Colour controls * Contrast, Vibrance, and Color Temperature join Color & Tone. Contrast pivots around middle grey before tone mapping. Vibrance boosts muted colours more than vivid ones. Color Temperature warms or cools the image at constant brightness. The defaults leave the image unchanged. ### Stable shadows * Shadows no longer jump every 2 blocks while you walk. Iris snapped the shadow camera to a 2-block grid and the shadow warp moved with it, so every shadow was redrawn in a new place at each snap. * The shadow warp has a linear core around the player. It covers 5 blocks on Low, 7.5 on Medium, 10 on High, and 12 on Ultra. The core moves in whole shadow texels, so shadows inside it keep their texel alignment while you walk. They shift by less than half a texel once per 8 blocks, when the rotation pivot moves to the next cell. * Shadows outside the core follow the camera in steps of one core texel, 0.04 blocks on Medium, instead of being redrawn at each snap. * The sun rotates the shadow map about the centre of the camera's 8-block cell. Shadow edges crawl at about the same rate as before while time passes. * On Medium, shadow texels are smaller than before from 3.7 to 22 blocks. Right at the feet they are 1.5 times larger, and at the shadow map edge they are 1.36 times larger. * The shadow pass uses Iris's `cameraPositionInt` and `cameraPositionFract`, so the texel alignment stays exact far from the world origin. ### Stable shadow projection * Shadow Projection has two modes. Sharp keeps the magnified core near the player, and distant shadow edges slide slightly as you walk. Stable uses one linear, texel-aligned projection, so every shadow at every distance stays still while you walk and only re-phases by under half a texel once per 8 blocks. Stable is on in High and Ultra, where texels are 0.125 and 0.078 blocks. * In Sharp mode, the minimum shadow filter width grows from 0.75 to 1.75 texels toward the edge of the shadow map, which hides the stair steps of the coarse distant texels. ### Water reflections * Water normals are stored at 16 bits per channel. At 8 bits a reflected ray could be off by 1.9 degrees, about as steep as the waves, which drew stepped contours in calm-water reflections. The error is now below 0.01 degrees. * Reflections that waves tilt below the horizon take the second bounce off the water instead of the dark ground colour. This removes dark speckles at grazing angles on native and Distant Horizons water. * Waves too small for a pixel add their slope variance to the sun glint roughness instead of disappearing, following Bruneton, Neyret, and Holzschuch (2010). The glint keeps its strength where waves fade with distance. Native and Distant Horizons water share this filter. * SSR hits receive fog along the reflected ray, so reflected hills match the haze of the hills themselves. * Waves fade into glint roughness once a wavelength spans less than about six pixels, instead of about two. Distant water no longer breaks into horizontal streaks where each pixel caught a different wave slope. * Water side faces use at most 2 blocks of water depth. They previously used the distance to whatever lay behind them and turned opaque blue. * Water reflects the sky only where it is nearly open to the sky. In caves it reflects a dim ambient instead, and SSR still shows the cave around it. * Water SSR is on in the High and Ultra profiles. * Water reflects the sky only where the sky is directly overhead, at sky light 15. Under an overhang or at a cave mouth, sky light 14 or less, it reflects dim ambient light instead of bright sky. * An SSR ray that crosses a surface between two samples now counts as a hit even when the surface depth changes across that step. These rays previously missed and fell back to the sky, which scattered bright shards over water under cave ceilings. * Refraction no longer pulls sky pixels into water that has a floor behind it. ### Falling water * Steep water faces carry long whitewater streaks that stream down at about 5 blocks per second. Three layers of detail run at slightly different speeds, and each layer fades to its average once it is smaller than a pixel, so far waterfalls do not flicker. * Falling water is an even, aerated white-blue with soft streaks. Thin parts are light blue-green and thick parts are white. Foam takes sunlight, sky light, and block light, and it hides most of the scene behind the fall, so a shaded waterfall no longer reads as a striped pillar. * River and lake surfaces keep the normal waves. The streaks apply only to faces steeper than about 27 degrees. * Clouds now show through water. A waterfall in front of the sky previously showed a clear sky with the clouds cut out. ### Underwater * The water surface seen from below is clear straight overhead and blends smoothly into a mirror of the water below at shallow angles. It reflects about 2% straight up and everything beyond the critical angle of about 48.6 degrees. Waves wobble the view through the surface. With SSR on, the mirror reflects the floor and nearby blocks. * The reflection angle follows the visible water face, including waterfall side faces. * Sunlight under water fades over the distance it travels through the water. The shadow map already stores the water surface depth, so floors turn bluer and darker with depth. A vertical water face, such as a waterfall, counts as 1 block of water. * With Volumetric Light on, underwater light shafts come from the shadow map. They follow the refracted sun, fade with depth, stop under blocks, and carry caustic beams when Caustics is on. Light Shaft Strength scales them.

## v2 ### Physically based soft shadows * Replaced the fixed texel-radii PCSS heuristic with a physical penumbra: the sun's angular radius (0.0093 radians, shared with the visible sun disc) drives similar-triangle softening from the blocker's height, so shadows are contact-sharp and widen with caster distance like real area-light shadows * Converted filter radii from world units to local shadow-map texels through the closed-form distortion derivative, so the same caster blurs the same amount regardless of its position on the distorted map; depth and lateral scale now read `shadowProjection` directly, adapting to resolution and shadow-distance settings * Added slope-scaled receiver bias derived from N·L and the local texel size, replacing constant depth offsets that were tuned to one resolution * Unified shadow-map projection across terrain, entities, native water, and DH water through one shared receiver function with a world-space normal offset; water glints and DH water glints previously projected with no receiver offset * Derived the blocker search radius from the physical maximum penumbra and clamped it to the filter-quality sample budget ### Underwater continuity * Replaced the binary in-water switch with a continuous submersion factor: the water composite and final pass probe the rendered, displaced water surface above the camera and measure the eye's depth below it, ramping over half a block * The probe now also measures the plane from nearby water-surface pixels when the straight-up view cannot see it, so level and downward views no longer snap to the engine's binary flag while swimming or diving * Water Fresnel, the refraction index flip, the surface's sky-reflection weight, atmospheric-to-underwater fog handover, and the underwater wobble, blur, and FXAA blend all interpolate by that factor, removing the hard pop when diving and the flicker while swimming at the wave line * Transmitted content below the surface switches to the refracted sky early in the ramp instead of at its midpoint; an eye just under the surface now sees the Snell window it physically should, without the dark band that appeared between the window and the horizon after submerging * Underwater volume integration follows the ray: upward rays stop at the water-plane crossing, so above-water scenery seen during the ramp and sky slivers at the shore no longer receive full-depth murk * The engine's in-water flag only seeds the factor when no surface is visible overhead, so eyes above a wave trough render the clean above-water view even while the block state still reports submerged * Water and Distant Horizons water sun glints hand over to the sky-lit estimate at the shadow range, matching terrain, instead of cutting to zero; the horizon keeps its sparkle ### Shared surface optics * Replaced the separate highlight formulas with one GGX BRDF shared by materials, water, glass, and puddles: Trowbridge-Reitz distribution, height-correlated Smith visibility, and Schlick Fresnel, with a roughness floor of 0.045 that broadens very sharp highlights to reduce aliasing; the previous distribution clamp flattened polished highlights, and the water and material paths mapped roughness differently * Material direct diffuse weights by `(1 - metalness) * (1 - F)`, and back-facing light or view directions return zero before constructing the half vector * Material reflectance keeps all three colour channels in an RGBA16F `colortex8`, so authored conductors retain coloured reflectance including the gold/iron distinction and HDR water highlights survive the buffer * Reflection normals use octahedral encoding in the existing two channels; reconstructing an always-positive view-space Z previously lost normals in the opposite hemisphere * Environment reflections use a polynomial fit to the correlated GGX hemispherical integral offline, validated on 483 held-out angle and roughness pairs; the fit adds no texture or runtime dependency and preserves RGB conductor colour * Only the sky-derived portion of metal ambient lighting gives up energy to environment reflections; block light, held light, dimension lighting, and ambient floors keep their material tint, so enabling reflections no longer dims torch-lit metals * Puddles use water Fresnel at the perturbed surface normal instead of a fixed 15% minimum plus a separate large reflection blend * Transparent blending partitions reflection and body opacity before converting to straight alpha (`F + (1 - F) * a`), so reflections keep their full weight after blending instead of being reduced by alpha a second time * Water uses unpolarized dielectric Fresnel at an index of refraction of 1.333 (normal-incidence reflectance about 0.0204), shared by native and Distant Horizons water ### Deferred water and reflections * Added a deferred pass that copies the opaque scene to `colortex9` before translucent draws; the water composite reconstructs the surface from `colortex3` markers and `colortex8` unattenuated direct specular light plus skylight exposure, adding eight bytes per pixel per buffer set * Submerged cameras now blend visible clouds into the scene and the snapshot before water and other translucents draw; the former late cloud pass skipped underwater views and left a cloud-free sky in the water background, and `cloud_view.glsl` shares one visible cloud field between the air pass and the underwater snapshot * Rewrote SSR in `screen_trace.glsl` as interval tracing: rays clip to the near plane and screen bounds, step along the dominant projected pixel axis, and test the depth interval between adjacent samples instead of isolated points, which previously let a ray step over a wall's depth slab; seven refinement iterations and a final thickness check reject false hits, and the edge fallback transition shrank from 28-32% of the screen to 6% * SSR is now opt-in: every profile and the default settings compile it out, and materials use sky-only reflections in Medium, High, and Ultra; reselect a preset after updating to clear saved SSR settings * SSR returns its fallback without tracing underwater, and its sky fallback traces the same animated 3D cloud density and light attenuation as the visible sky; cloud reflections in water use fewer samples and skip the cirrus layer * Rebuilt water waves as four travelling components at 5.5, 2.3, 1.0, and 0.42 block wavelengths whose angular frequency follows deep-water dispersion; normals use analytical height derivatives and the submerged underside opacity follows a slope-weighted cue from the same phases * Water refraction samples the deferred opaque snapshot at the original screen coordinates; DH water now compares reconstructed native and DH positions for occlusion, so native terrain behind water no longer erases the water face while native foreground still occludes it, and the distance-only alpha fade that left gaps when native water was absent is gone * Outdoor light shafts use visible sky depth as their source, so bright opaque walls no longer count as sky, and underwater light shafts are disabled * DH terrain keeps its supplied average texture colour instead of adding world-space material noise and a second desaturation pass, and the separate white metal glint is removed; native and DH surfaces share one fog distance law, and only cleared depth 1.0 counts as sky ### Glass and generated materials * Glass defaults to F0 0.04 and smoothness 0.90 instead of inheriting the polished-block material; its sky fallback excludes the solar disc, and texture detail uses ambient lighting, removing a broad coloured wash on sun-facing panes * Coloured sunlight transmitted through glass onto nearby surfaces now uses an opacity-weighted tint, `(1 - opacity) + opacity * textureColour`, instead of a fixed 90% tint and 1.6 saturation boost * The shadow colour target now carries caster opacity and reserves alpha code 255 for water; only tagged water applies animated caustic modulation, so moving bright stripes no longer show through glass, and translucent casters join the blocker search so their distance controls penumbra size * Generated vanilla metal textures keep their diffuse body and use F0 0.04 with smoothness 0.60 (Natural) or 0.72 (Pronounced) instead of being treated as full conductors whose sky-only reflection dominated unrepresented surroundings; authored LabPBR conductors keep supplied metalness and reflectance * Held and dropped block items resolve the same material classes as placed blocks through `currentRenderedItemId`, sample terrain shadows and cloud visibility instead of bypassing the shadow map, and clear their reflection metadata so the world cannot reflect through the hand * Added steep-parallax occlusion against the LabPBR height field; flat maps (alpha 255 everywhere, the default when a pack omits height) return on the first probe and pay no march cost ### Clouds, sun, and night sky * Replaced 2D noise slices with continuous 3D value noise for cloud billows and erosion; density now varies in all three dimensions and the flat alto layer is removed, leaving one thin cirrus layer * Cloud RGB and opacity share one exponential integration instead of an opacity-only power adjustment; each occupied sample probes density three times along the light direction with Beer-Lambert transmission and a two-lobe Henyey-Greenstein phase approximation * The sun is an antialiased disc at HDR intensity 24 with the 0.0093-radian angular radius shared with shadow penumbra construction, plus a separate angular halo so it stays visible through the tone curve * Night sky uses a continuous horizon-to-zenith gradient independent of the engine's sky-mesh vertex colours and dims with weather; moonlight now varies with moon phase and ambient lighting is less blue * The Milky Way is fainter with a smooth band structure, and stars use Iris's star render stage (`MC_RENDER_STAGE_STARS`) instead of guessing from grayscale vertex colours ### Performance * Fused FXAA and contrast-adaptive sharpening into one pass sharing a single 3x3 neighbourhood, roughly halving full-resolution fetches for those effects; the fusion reproduces the previous two-pass output

## v1.5 ### Materials alpha * Added a shared lightweight material library with LabPBR 1.3 normal, AO, perceptual smoothness, F0/metal, and emissive decoding; absent maps retain a neutral matte fallback * Added Natural and Pronounced built-in material styles; the stronger choice only changes generated vanilla metal/polished smoothness and never alters LabPBR resource-pack data * Terrain, entities, and the hand/held-item pass now use tangent-space normals and an inexpensive GGX/Smith/Schlick direct response without replacing the existing lighting model * Extended the material path to translucent water and glass: genuine resource-pack normal detail can perturb procedural water without flattening absent-map waves, while glass reads LabPBR normal, AO, F0, smoothness, and emission channels * Added conservative built-in metal and polished-mineral classes for vanilla textures; ordinary stone, wood, soil, and foliage deliberately remain matte * Reused `colortex3` for opaque material normals/reflection strength, with separate class ranges for opaque materials, portals, puddles, and water * Added Off / Sky Only / SSR material reflection tiers and profile defaults: Low compiles materials out, Medium uses sky reflections, and High/Ultra permit material SSR * Added a dedicated Materials options page with Built-in / LabPBR Resource Pack source and specular-strength controls ### Distant Horizons * Added dedicated compatibility-profile `dh_terrain`, `dh_water`, and future-ready `dh_shadow` programs for the Overworld, Nether, and End * DH terrain reuses Solstice's sky light, block light, weather color, cloud shadows, foliage response, emissive classification, and dimension lighting * Added distance-filtered world-space material detail for grass/leaves, stone, deepslate, wood, dirt, sand, snow, terracotta, Nether stone, metal, and lava; this restores surface breakup where Iris cannot expose block-atlas UVs to the DH shader path * Corrected DH grass blocks being treated as translucent foliage and metal being treated as emissive; metal now receives a restrained broad highlight instead * DH water uses biome color, Solstice's user water tint, distance-stable waves, physical Fresnel, sky reflections, light glints, and transparent blending * Native and DH depth now share one scene-classification/reconstruction helper * Atmospheric fog preserves the native look near the player, thins beyond the native horizon for readable vistas, and dissolves only at the outer DH render edge * Clear-weather DH atmosphere was opened further so distant landforms retain colour and contrast; rain, thunder, dawn mist, and dimension atmosphere remain denser * Added a defensive Overworld cave-face rejection for fully enclosed DH geometry below sea level, preventing stale cave LODs from leaking through the native/DH handoff * Very distant DH color now receives restrained aerial chroma/contrast compression, reducing fluorescent repeated color across large LOD triangles * Clouds and half-resolution reconstruction no longer mistake LOD silhouettes for sky * Light-shaft occlusion, underwater absorption, and native-water SSR now see DH geometry * Sun glare now uses a soft 16-point visibility probe plus angular broad/core response, so terrain occlusion and crossing the player's FOV edge fade continuously instead of switching the effect off * SSAO, puddle metadata, and material-style surface effects remain native-only, avoiding wasted work and false seams on low-detail LOD meshes * DH shadows are deliberately disabled until their all-LOD pass meets the performance budget; the depth-only program is present for future profiling * Base rendering remains guarded by Iris's `DISTANT_HORIZONS` feature macro, preserving the existing non-DH path ### Weather and color * Volumetric cloud bodies now combine vertically decorrelated erosion fields with flatter bases, taller coverage-driven tops, and billowed internal density instead of extruding one 2D weather shape through the entire layer * Reduced first-hit cloud extinction so the march reveals multiple illuminated density layers; High and Ultra add a second long-range sunlight probe, while clear-sky bounce and an inexpensive multiple-scattering floor keep shadowed daytime lobes blue-white rather than charcoal without brightening storm clouds * Underwater sky rays now use solid depth behind the water surface to generate and merge the same cloud layer seen above water; water extinction and the Snell window attenuate that layer afterwards, so submerged views can no longer reveal a cloud-covered moon * The shared sun/moon visibility probe now multiplies terrain visibility by resolved cloud transmittance, keeping celestial discs, halos, glare, and light shafts consistent * Rebuilt shooting stars as sub-second meteors with a compact warm head, narrow tapered blue-white plasma trail, breakup flicker, and one shared life envelope; the old multi-second moving glow segment and lingering-looking smear are gone * Stars, meteors, moonlight, and the lunar halo now use the smoothed weather state, preventing celestial clarity from snapping ahead of cloud recovery after rain * Rain atmosphere now uses an Iris-smoothed weather state: storms close visibility quickly, while fog, cloud cover, lighting, reflections, and sun glare recover gradually for twelve seconds after rain instead of revealing the full DH landscape at once * Rain/DH fog is substantially denser at long range, matching the short visibility expected from humid heavy weather while preserving nearby silhouettes * Added Natural and Vivid color grades alongside the legacy Classic response; Natural is the new default and tone-maps luminance rather than RGB channels independently, preserving hue through highlights * Natural grading applies restrained highlight/shadow chroma compression, gamut compression, and weather-aware white balance; default saturation is now neutral rather than boosted * Cloud macro shaping no longer suppresses an enormous low-frequency region around the camera column, removing the persistent clear crater seen when looking straight upward * DH water now rejects pixels covered by native opaque depth and fades in across the native water range, preventing ocean bands from drawing across portals, terrain, and builds * Top-down DH water now matches native water's 2% normal-incidence Fresnel, body tint, and transparency instead of becoming a bright, highly reflective sheet * Underwater extinction now follows the Water Murkiness setting for native and DH geometry; suspended-particle haze closes long-distance visibility, and the water surface softly limits the above-water scene to a physical Snell window instead of exposing the entire world * The defensive DH cave filter now rejects fully enclosed zero-skylight Overworld LOD faces at any elevation, covering modded caves and incomplete world-generation columns * Sunrise atmospheric color is now confined around the sun instead of reflecting as a straight neon horizon band; twilight cloud bodies stay neutral while their lit edges warm ### Capture-driven performance * Used an AMD RenderDoc counter capture to identify the full-resolution effect merge, volumetric clouds, final output, atmosphere/water, and AO mask as the meaningful Solstice post costs; the already inexpensive bloom and portal-blur passes were left unchanged * Reworked cloud reconstruction to use its existing alpha coverage instead of rereading native and DH depth for every neighbouring half-resolution texel * The final effect merge now builds half-resolution coordinates once and shares native depth samples between surface effects and light shafts, while underwater shafts continue using the solid depth hierarchy * The merge reads the existing 1×1 celestial visibility result and skips all shaft-buffer reconstruction when the light source is off-screen, fully occluded, or otherwise inactive * FXAA reuses the final pass's existing centre colour instead of sampling it twice at full resolution * Volumetric cloud rays now hoist weather and lighting constants out of the density loop; primary density remains evaluated at every step while the smoother solar-occlusion probe is reused for one adjacent occupied step through the existing temporal reconstruction * The terrain path now reuses its vertex distance and per-fragment direct-light colour, removing repeated length, celestial normalization, and weather-light calculations from the indexed chunk draws highlighted by the capture ### Gameplay polish * Added Survival, Balanced, and Builder lighting styles as a visual preference independent of Low/Medium/High/Ultra; the modes adjust night illumination, sky-light response, block light falloff, held light, and interior indirect floors without changing daytime exposure * Renamed Night Darkness to Night Brightness so the slider direction is unambiguous * Added optional low-strength contrast-adaptive sharpening after FXAA, with neighborhood clamping and flat-region rejection to restore texture clarity without strong sky noise or edge halos; underwater sharpening is skipped ### Render paths and Minecraft 26.2 * Added explicit lightweight programs for damaged blocks, block entities, translucent block entities, beacons, items, particles, translucent particles, translucent entities, lightning/dragon beams, armor glint, emissive eyes, and translucent held objects in the Overworld, Nether, and End; lines deliberately use Iris's documented `gbuffers_line` to `gbuffers_basic` fallback * Translucent entity and block-entity passes retain forward lighting but no longer write opaque material/SSR records into `colortex3` * Added `item.properties` and separate main/off-hand light evaluation, allowing warm, soul-blue, redstone-red, amethyst/end-purple, and plant-orange held-light colors * Replaced hardcoded cutout thresholds with Iris's `alphaTestRef` in terrain, entity, hand, generic textured, lit textured, shadow, and special overlay paths * Enabled Iris's separated translucent entity/block-entity draws and mixed particle ordering; beacon beams remain non-depth-writing so they cannot carve holes through fog * Expanded current content metadata for Spring to Life foliage, golden dandelions, pale-garden plants and lights, trial spawners/vaults, copper bulbs, current emissive mobs, and the Minecraft 26.2 sulfur/cinnabar building families

## v1.4 ### Reduced-resolution post pipeline * Bloom moved from two full-resolution passes to quarter-resolution `colortex1/2`, with a soft-knee threshold, firefly control, and a wider lower-intensity filter * Volumetric/blocky clouds, SSAO, and light shafts now render at half resolution * The final effect merge performs depth/class-aware reconstruction so cloud, AO, portal, and shaft samples do not bleed across terrain silhouettes * Disabled effects now disable their composite programs, including dimension-specific paths ### Temporal skies and cloud lighting * Volumetric clouds use a frame-varying march offset and a persistent cloud-only history * History reprojects with the previous camera/model-view/projection data, clamps to the current 3x3 neighborhood, and rejects large camera jumps or reactive cloud changes * Cloud direct light was rebalanced so the forward silver lining stays bright without turning the entire cloud body white; bases retain stronger tonal separation * Full-scene TAA remains intentionally absent ### AO, shafts, and portal light * The repeated sun/moon visibility gather is now a single 1x1 frame-level pass * Light shafts moved to a half-resolution buffer * Full-resolution 16-tap portal gathers were replaced with a downsampled portal-light mask and two inexpensive separable blur passes * SSAO moved from ten samples per full-resolution pixel to eight samples per half-resolution pixel ### Reflections, shadows, and final image * `SSR_QUALITY` adds profile-controlled 16/24/40-step caps, matching refinement tiers, tighter hit thickness, Fresnel gating, and distance/travel rejection * `SHADOW_FILTER_QUALITY` adds 4/8/12-tap PCSS tiers; blocker samples scale with the tier * The shadow vertex pass reuses the visible terrain foliage deformation in player space * The old four-neighbor edge blend was replaced with low-cost directional FXAA * The filmic curve has a softer highlight shoulder and a gated near-black lift that leaves true black and genuinely dark caves anchored

## v1.3 ### Reflections * SSR rewritten as a screen-space march with perspective-correct depth interpolation (1/z is linear in screen space): every step lands on a fresh pixel, so distant reflections resolve crisply instead of skipping and smearing * No matrix math inside the ray loop anymore as depth linearization is two fused ops, so the rewrite is both sharper and cheaper * Step count adapts to the ray's on-screen length (14 to 40) to hit thickness scales with distance and validation is tighter, cutting ghost hits behind thin geometry ### Clouds * Volumetric cloud lighting now uses real scattering formulas: a dual-lobe Henyey-Greenstein phase function (the standard model for light in water droplets) gives a bright silver lining toward the sun and soft backscatter away from it, a two-term Beer transmittance approximates multiple scattering so cloud interiors stay luminous instead of going black, and a powder term darkens thin wispy edges * Cloud bases sit darker and flatter (height gradient) * Clouds drift about 4x slower and no longer morph constantly advect on the same wind vector, so a cloud moves as one body instead of its detail layers sliding at different speeds * Fixed a profile bug: Medium, High and Ultra now explicitly select Volumetric cloud mode * New Cloud Quality step 32; Ultra uses it ### Light sources * Block light (torches, lanterns, lamps) now follows the inverse-square law: the lightmap encodes distance to the source (vanilla light drops one level per block), so it gets remapped to real distance and attenuated with the same windowed inverse-square formula real renderers use for point lights. Light sources read as bright pools that fade fast, not an even wash * Held-light uses the same attenuation * Torch color documented as roughly a 1900K blackbody, matching real flame * Realistic Light Falloff toggle under Visuals; the old curve remains as the off state ### Glowing mobs & portal glow fix * Blazes, magma cubes, glow squids and allays are now emissive: their bright texels glow and feed the bloom pass, under the same Glowing Blocks toggle * Eye-glow mobs: enderman, spider, cave spider, phantom and guardian eyes emit with a high luma threshold, so the eyes burn in the dark while the body stays unlit - purple enderman eyes in a dark forest, red spider eyes in caves * Removed the portal glow prefilter: its point-sampled early-out produced hard on/off boundaries (torn rectangular notches in the glow). The gather now always runs within range and is perfectly smooth ### More real formulas & performance * Water depth uses true Beer-Lambert absorption with per-channel coefficients: red is absorbed within meters, blue survives, so depth turns teal for the physical reason rather than a hand-picked fade color. Underwater fog uses the same law * Purkinje shift: dark scenes drift toward desaturated blue-grey, matching how human rod vision behaves at night (toggle under Color & Tone) * Depth unprojection in the composite exploits the projection's symmetric structure: five terms instead of a full matrix multiply, across every SSAO/SSR/glow sample * The cloud march's sun-occlusion probe uses a cheaper 2-octave density (the light sample does not need full detail), cutting volumetric cloud cost by roughly a quarter ### Shadows & block light polish * Shadows upgraded to PCSS (percentage-closer soft shadows): a blocker search measures how far above the surface the caster sits, and the penumbra widens with that distance - the real behavior of sunlight as an area source. Shadows are contact-sharp at the base of a wall and progressively softer for tall trees. Fully lit pixels early-out after the 4-tap search, so most of the screen got cheaper while shadow edges got better * The PCF disk is a noise-rotated Vogel spiral (8 taps) instead of a fixed 4-tap square, removing the boxy shadow edge * Light patches projected through stained glass follow the same penumbra physics * Block light falloff rebalanced: inverse-square core plus a cubic near-field term, because glowstone and lanterns are area sources with indirect bounce, not bare point lights ### Water & portal polish * Water fresnel replaced with true Schlick using water's physical F0 = 0.02 (from its refractive index): 2% reflection looking straight down so you see into the water, climbing to a near-total mirror at grazing angles * Wave normals and rain ripples flatten with distance: far ripples are smaller than a pixel, so full-strength normals only produced aliasing speckle across the ocean * Portal glow gather rebuilt as a Vogel spiral disk rotated by interleaved gradient noise: smooth pool of light with a soft edge instead of banded dither blotches, with a tighter radius and gentler intensity ### Glass * Stained glass throws vivid colored light: the tint that sunlight picks up passing through translucent blocks is now saturated, so a stained glass window paints strong colored patches on the floor behind it * Windows catch the sky: glass gets a fresnel reflection of the sky gradient and a sun glint at grazing angles * Glass Reflections toggle under Water options

# Solstice Changelog ## v1.2 ### Wet weather * Rain puddles form on exposed ground while it rains and dry up gradually afterwards * Puddles form as larger connected pools rather than scattered specks, and grow with rain intensity * Animated rain ripples on the puddle surface * Puddles reflect the sky, show a sun glint at grazing angles, and mirror nearby terrain and builds through screen-space reflections when SSR is on * Wet ground darkens during rain * Puddle Coverage slider; Low profile turns puddles off ### Portals * Nether portals glow and cast purple light onto surrounding blocks * Toggle under Nether & End options; off in the Low profile ### Snow * Snow sparkles: crystal glints that catch the light and shift with your view angle, on snow layers, snow blocks, powder snow and snowy grass * Snow gets a subtle cool brightening and no longer darkens or forms puddles when it rains elsewhere in the world * Sparkle Strength slider under Visuals ### Fire * Fire and campfire flames flicker: emission pulses with layered waves plus noise, so the bloom breathes like a real fire * Flame color grading: white-hot core fading to deep orange at the edges; soul fire grades to cold blue-white * Fire blocks sway gently at the tips; campfire logs stay put, only the flame pixels are affected * Lit campfires only - unlit ones no longer glow * Living Flames toggle under Visuals ### Glowing blocks * Light sources (glowstone, sea lanterns, shroomlight, froglights, lanterns, torches, campfires, magma, crying obsidian and more) glow properly and feed the bloom pass * Ores, amethyst, sculk and enchanting tables get a subtler glint that shows in dark caves * Glow Strength slider; enabled on every profile since it costs almost nothing ### Night sky * Procedural milky way band on clear nights, scaled by Star Brightness * Shooting stars streak across the sky every few seconds * Green-blue aurora on clear nights in snowy and cold biomes, rolled per in-game day (uses Iris biome temperature data) * All three have their own toggles under Sky & Clouds ### SSAO * Depth-based ambient occlusion: soft contact shading in corners and under blocks * 10 taps with dithered rotation, smooth occlusion falloff instead of hard cutoffs, and a distance fade so far terrain stays clean * Strength slider; enabled on High and Ultra profiles ### Other * Light shafts now fade out as the sun or moon leaves the screen edge instead of smearing across the corner of the view * Screen-space reflections use a dithered ray start and finer hit refinement, which hides step banding on water and puddles

# Solstice Changelog ## v1.1 ### Clouds * Rebuilt Blocky cloud mode as true 3D boxes: voxel-traced height, lit tops and shaded sides, clouds cast shadows on each other * New Blocky Cloud Height slider * Added an About screen and more option tooltips ### Nether & End * Fixed the pack breaking outside the overworld. The dimension folders were incomplete, so terrain, post-processing and final output never ran in the End. Every shader program now runs in all three dimensions * End: darker violet lighting, aurora ribbons drifting across the sky, stars, and shadows cast from the End's fixed light angle * Dragon death rays and explosion flashes are pushed into HDR so bloom makes them glow * Nether: biome-tinted fog that warms toward the lava below and darkens toward the ceiling, a slow haze backdrop that matches the fog color at the horizon, a faint ember glow, and heat shimmer over distant terrain (nearby blocks stay solid) * New Nether & End options screen: End Aurora toggle and strength slider, Nether Haze, Heat Shimmer ### Lava * Lava surfaces now move: slow molten swells, heavier and slower than water waves, using the shared Wave Strength slider * Lava is fully emissive with a traveling heat pulse that feeds the bloom pass * Works in every dimension. Toggle is under Water options as Lava Waves; the Low profile turns it off along with water waves ### Fixes * Removed a duplicate fogColor declaration that stopped the water shader from compiling on strict drivers * Nether backdrop no longer shows grey smears or a visible seam where distant terrain meets the fog

# Solstice v1.0 A lightweight semi-realistic shader pack built for a high performance-to-quality ratio. (developed and tuned on an RX 6600 at 1440p). ## Features - Real-time PCF shadows with per-pixel distortion (sharp near, cheap far, no warping on builds) - Colored translucent shadows: sunlight through water turns blue with animated caustics - Volumetric raymarched clouds with self-shadowing, silver linings, wind drift, and a high cirrus layer - Cloud shadows on terrain, matching the sky overhead - Screen-space god rays (sun/moon, above and below water) with source-occlusion checks - SSR water reflections - terrain, trees, and builds mirrored on water; depth-aware - (clear shallows, mirror depths) with sky-gradient fallback - Procedural fluid water: Gerstner-style traveling waves, sea-state variation, rain ripples - Unified atmospheric fog: fog is the sky gradient (aerial perspective), render-distance - fade dissolves into it seamlessly - Full weather system: bright diffuse overcast, dark slate thunderstorms, localized lightning - flashes that light the cloud deck from within, emissive lightning bolts - Procedural circular sun and phase-accurate circular moon - Dynamic held-item lighting (torch in hand lights the world) - Dark survival nights, warm Nether ambient (adjustable in-game) - HDR pipeline: bloom, ACES tonemapping, FXAA-lite edge smoothing, dithering ## Settings Four profiles: **Low** / **Medium** / **High** / **Ultra** (shader options screen), plus four option screens: Shadows, Sky & Clouds, Visuals, Color & Tone. Notable sliders: Cloud Coverage, Cloud Speed, Nether/End Brightness, Fog Density. ## Requirements Iris (bundled with Fabulously Optimized). OptiFine untested; Iris-exclusive uniforms (thunderStrength, lightningBoltPosition, hasSkylight) degrade gracefully if absent. ## Performance notes Shadows are the dominant cost, lower Shadow Resolution/Distance first. Clouds cost only on sky pixels (Cloud Quality slider). SSR costs only near water. Everything else is cheap. ## Authors _d0mkaaa_