VESPERA Vanilla+ RT Shaders pour Minecraft 1.20.1, 1.21.1

VESPERA Vanilla+ RT keeps Minecraft looking like Minecraft: same colours, same textures, same blocky charm. What changes is the light. Torches, lanterns, lava and glowstone become real point lights with soft, ray-traced shadows, so a torch in a cave actually lights the cave, and a pillar in front of it actually casts a shadow.

Features

• Ray-traced block light: every glowing block is a coloured light source. Shadows are traced through a voxel grid of 96×64×96 blocks around you, down to 1/8 of a block, so fences, stairs, leaves and glass behave correctly.
• Coloured light: soul fire is blue, redstone is red, lava is orange. Bounce light picks up the colour of nearby sources.
• Held and dynamic lights: torch in your hand, glowing items on the ground or in frames, blazes, magma cubes, glow squids and allays light up their surroundings.
• Sun and moon shadows: soft shadows with contact hardening (PCSS), tinted by stained glass and water.
• Atmosphere: ambient occlusion, sun rays in the air and underwater, water waves and reflections, underwater caustics, a soft glow around fire.
• Overworld, Nether and End.
• Quality profiles: Low / Medium / High / Ultra, plus detailed options in the shader menu.
• Styles: lava (Vanilla / Balanced / Cinematic), Nether brightness (Vanilla / Balanced / Gloomy), End brightness, natural or vanilla rain.
• Fog follows the game: render distance, water, Blindness and the Warden's Darkness work as in vanilla.
• Every option has a tooltip. English and Russian menu.

New in 1.2

On by default, the look stays vanilla:

• Distant Horizons support: far chunks get vanilla-style sky and block light (no ray tracing or sun shadows there), blend smoothly into the normal chunks, and the fog moves to the edge of the far chunks.
• Water refraction: the bottom ripples under the waves; near the shore the water is clearer, in the deep it is darker and bluer.
• Lightning light: in a thunderstorm each strike briefly lights the ground, buildings, mobs and water around, flickering. Under a roof and in caves there is almost no flash.
• Rainbow: when the rain ends and the sun is low, a rainbow with a faint second arc appears opposite the sun and fades over a few minutes. Never in snow, at night or with the sun high.
• Soft snowflakes: round flakes of different size and brightness, without the repeating pattern of the vanilla texture; they fall as in vanilla. The "Snow look" option switches back to vanilla snow, "Snow amount" sets how much falls. Snow stays white, as in vanilla.
• Snow sparkle: rare tinted glints on snow in sunlight; the snow shimmers when you move. No glints far away or in rain.
• Fractal lightning (on by default, "Lightning look"): a branching bolt with a white core and a violet glow instead of the vanilla zigzag; blocks hide it and water reflects it.

Off by default (turn them on in the shader menu):

• Rain puddles: puddles on flat open ground appear after a minute or two of rain and dry out over a few minutes; they reflect the sky and surroundings, and drop rings spread across them and across water. Fewer puddles on grass.
• Weather wind: wind has a direction and gusts, leaves and grass lean with it. Light in clear weather, strong in rain and storms, and the rain falls slanted.
• Haze around lights: in caves and at night the light of torches, lamps and lava scatters in the air as a halo 3-4 blocks around the fire; it does not pass through walls.
• Sunlight through windows: sun falling through a window, a skylight or a cave entrance softly lights the room around it with warm light; it does not pass through walls.
• Moon phases: nights are brighter at full moon and darker at new moon, moon shadows are weaker.
• PBR: bumps and highlights (its own submenu): relief built from the brightness of the vanilla textures, sun and moon highlights on metal, ice, quartz, polished stone, ceramics and gem blocks, highlights from torches, lamps and lava, reflections on metal and smooth stone. Resource packs with labPBR maps (_n, _s) are supported. This moves away from the vanilla look, so it is off.
• Cinematic & HDR submenu: eye adaptation (a cave slowly gets up to 2× lighter, a night under the sky stays dark), vignette, depth of field (focus on the centre of the screen, your hand stays sharp).

And one optional extra that is switched on but does nothing by itself:

• HDR on HDR monitors with the optional rrtt217's HDR Mod: normal colours stay as in SDR, fire, lava, the sun and highlights shine brighter than white. Without the mod nothing changes.

Recommended for the full experience: Distant Horizons together with Distant Horizons SeedGen — far terrain to the horizon in the same vanilla light, generated quickly from the seed.

Requirements

• Minecraft 1.20.1 or 1.21.1 (the versions it is tested on; the pack is also marked for other versions from 1.20.1 to 26.3, those may work but are not checked)
• Iris with Sodium, Fabric or NeoForge (tested: Iris 1.7.6 on 1.20.1, Iris 1.8.12 on 1.21.1)
• A GPU with OpenGL 4.3 (compute shaders and 3D images are used). Tested on NVIDIA; AMD and Intel feedback is welcome.
• Distant Horizons is supported (new in 1.2), also together with Distant Horizons SeedGen for fast far-terrain generation. On 1.20.1 with Sodium DH needs Indium. Sun rays and water reflections do not work on far chunks. Tested: DH 3.3.3 + SeedGen 0.9.1 on 1.20.1, DH 2.3.2 on 1.21.1.
• Not supported: macOS, OptiFine.
• Optional: rrtt217's HDR Mod for HDR output.

Checked on 1.21.1 (NeoForge with Iris 1.8.12, and Fabric with Iris 1.8.8 and Distant Horizons 2.3.2): the 1.2 options load and work, including all optional ones at once.

Performance on a GTX 1660 SUPER at 1080p, render distance 12, with Distant Horizons installed (open scene / cave with many lights): Low ~118 / 90 FPS, Medium ~86 / 73, High (default) ~70 / 57, Ultra ~58 / 48. Without Distant Horizons the numbers are higher. The optional extras together cost about 10% outdoors and 25% in caves.

Installation

• Download the ZIP.
• Put it into the shaderpacks folder (Iris: Options → Video Settings → Shader Packs → Open Shader Pack Folder).
• Pick VESPERA Vanilla+ RT in the shader list.

Status

Tested in-game on an NVIDIA GTX 1660 SUPER, Minecraft 1.20.1, Iris 1.7.6: Overworld, Nether, End, water, rain, snow, thunderstorms, held lights, mobs, Distant Horizons 3.3.3. The 1.2 options were checked in-game on screenshots; motion details (drop rings, flake sway, the bottom rippling under water, how fast the rainbow fades) were not reviewed separately. Every option and profile passes automatic shader compilation checks.

Not checked yet:

• AMD and Intel GPUs.
• HDR output on a real HDR monitor. It follows the documented requirements of the HDR Mod and was compared with the mod's sources, but it has not been tried on an HDR display. White may turn out too bright: lower "HDR highlight brightness" (0 = like SDR).

If something looks wrong or the pack does not load, please send your latest.log.