AuroraFX Iris - Photorealistic Ultimate
========================================

This build is a substantial rewrite of the original AuroraFX pack.
It is designed around Iris' deferred pipeline and its documented shadow
buffers rather than pretending to be hardware RTX.

PROFILES
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LOW       : close to original, performance first
MEDIUM    : recommended gameplay balance
HIGH      : strong shadows, AO, water, atmosphere
ULTRA     : cinematic lighting, volumetrics and detailed water
CINEMATIC : maximum quality; 4096 shadow map, 25-tap soft shadows,
            colored transparent shadows, volumetric light shafts,
            screen-space water reflections, animated caustics, AO,
            cinematic post processing and layered water normals.

IMPORTANT
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The shader includes explicit fallback definitions for every option used by
terrain_solid. This prevents the common WAVING_STRENGTH compile failure when
Iris processes the dedicated solid terrain program.

The colored-glass effect uses Iris shadowtex0/shadowtex1/shadowcolor0.
Transparent casters can therefore tint transmitted sunlight instead of
creating a simple black shadow.

The CINEMATIC profile is intentionally GPU-heavy. 4096 shadows + 25 taps +
volumetric ray marching + screen-space reflections are meant for high-end
GPUs. If performance is poor, use ULTRA or HIGH.

This is an original implementation inspired by techniques documented by Iris
and by the visual goals of modern Minecraft shaderpacks such as Complementary.
It does not claim to be hardware ray tracing.

ASSET
-----
The pack contains a dedicated 256x256 noise texture used to rotate/jitter
high-quality shadow kernels. This reduces repeating shadow sampling patterns
in CINEMATIC without needing a separate external texture pack.


SHADOW UPDATE
- CINEMATIC uses a PCSS-style blocker search with a variable penumbra instead of the old fixed 5x5 blur.
- The penumbra changes with blocker/receiver distance, keeping contact detail while softening naturally with distance.
- Rotated Poisson sampling removes the obvious rounded/grid-like blur pattern.
- Slope-scaled bias reduces shadow acne without erasing small contact shadows.
- Shadow resolution follows the profile: 512 / 1024 / 2048 / 3072 / 4096.
- CINEMATIC volumetric shafts are stronger and include a subtle sun halo.
