THIS IS NOT THE LATEST VERSION FOR 1.17.1.
COMPLEMENTARY IS NOT VERSION-DEPENDANT.
PLEASE JUST GET THE LATEST VERSION HERE: https://www.curseforge.com/minecraft/customization/complementary-shaders/files

Changelog:
- Improved reflection ray tracer for water/translucents which fixes incorrect reflections and reduces noise
- Improved TAA to no longer do jittering when moving
- Improved colored shadow calculation to fix wrong shadows with some resource packs and mods
- Tweaked the End dimension sky color and star distribution
- Tweaked water reflection ray tracer to better prevent lines appearing at the edges of water
- Tweaked sun/moon light glow on foliage during rain
- Tweaked PBR texture emission curve to look linear on low values as well
- Retweaked the color calculation of rainbows
- Support for Minecraft 1.7.10 is back
- Added "Double Reflection Quality" option. Enabled by default on the Extreme profile
- Added "Rainbow Style" option
- Added "Rainbow" Selection Outline mode
- Added "Entity Shadows" and "Block Entity Shadows" options. Both are disabled on the "Low" Profile
- Added "Hold Light Source" mode to the "Show Light Levels" option
- Added "Extended Lights" mod's leaves to the block.properties
- IntegratedPBR changes:
   - Added fancy emission to Amethyst Buds
   - Added subtle emission to the tiny shroomlight-colored pixels of Weeping Vines
   - Added "Alternative Command Blocks" option
   - Improved reflectance of a bunch of "should be shiny" materials including Diamond, Emerald, Amethyst, Quartz, and more
   - Improved Auto-Generated Normals. They are generally more noticeable in the distance now
   - Improved the Beacon block's look and made its texture visible
   - Tweaked emission of Copper Ore and Redstone Ore
   - Tweaked smoothness of Blue Ice, Calcite, Command Blocks and Honeycomb Block
   - Tweaked the brightness of Lit Furnaces, Sea Lantern, Jigsaw Block and Structure Block
   - Amethyst Buds now give purple light with Scene-Aware Colored Lighting
   - Reduced the intensity of Noise Coated Textures on Amethyst blocks
- Visibility inside lava is now affected by the Fire Resistance status effect
- Pixelated Shadows option can now be set to different resolutions
- Fixed inconsistent lighting on foliage during sunset/sunrise when Real-Time Shadows are disabled
- Fixed water caustics appearing in shadows on AMD Mesa drivers. Thanks to gri573
- Fixes for Iris:
   - Fixed reflections on water in the distance looking darker and not fading with the border fog
   - Fixed water surface having incorrect reflections when observed from underwater
- Fixed setting Optifine's "Render Quality" option to "2x" breaking TAA
- Fixed things behind campfire smoke flickering with TAA
- Fixed rainbows not being visible underwater
- Fixed rainbows appearing in caves or in the void
- Fixed beacon beam colors being slightly off or too bright in newer Optifine versions or Iris
- Fixed some OpenGL errors on AMD Mesa drivers
- Fixed name tag boxes and vanilla shadows of glowing entities having glow outlines
- Night Vision status effect now reduces the maximum water opacity to improve visibility to vanilla levels
- Specular Sky Reflections option now also decides if sun/moon shine will appear on blocks or not
- Specular Sky Reflections option is now enabled by default
- The "Vanilla AO Strength" slider now overrides the "Smooth Lighting Level" slider in Video Settings