Enforce a minimum roughness to 0.045 in PBR shaders to avoid div by zero and for consistency with Substance and UE/Unity

DRTVWR-559 Balance night scenes against release, nudge glow down a smidge, remove exposure correction from legacy fullbright balance PBR materials against legacy.

SL-19538 Followup -- scrub all possible sources of NaNs, make dynamic exposure controls not persist, limit exposure range, and do a debug gl pass.

SL-19281 Unify handling of haze and gamma between fullbright and not and move haze back to sRGB color space to stay consistent with sky colors.  Also fix broken "roughness" stuck at 0.2.

SL-19212 Resurrect glare and apply to PBR materials as well (and fix color mismatch in legacy alpha vs opaque).

SL-19147 Water quality pass.  Remove gl_FragDepth writes from sky rendering (optimization).  Incidental decruft.

Jonathan Goodman authored 2 years ago and David Parks committed 2 years ago

First pass of Screen Space Reflections

Approved-by: Dave Parks

SL-18190 Fix alpha not playing nice with water surface by split LLDrawPoolAlpha into two passes, one above water, one below water, and clip against water plane.  Currently brute forces two complete alpha passes, still need to cull against water plane and add support for fullbright shaders.

SL-18190 Water shader WIP.  Better parallax correction for sphere probes.  Reduce probe memory footprint.  Remove framebuffer copies and move to deprecate stencil buffer usage.

SL-18190 End of linear space odyssey -- just eat the conversions in atmosphericsFuncsF for sunlight and additive, but leave linear ambient in tact.

SL-17701 WIP -- Cleanup/refactor PBR lighting implementation and get parity between deferred and alpha passes for sunlight and IBL.