Changelog

1.4.1

Fixed black patches of ground with terrain mods (Badger's HD Terrain): stronger normals and particle lighting now touch only the game's own shaders.

New: caustics, the waves' light rippling over the shallow sea bottom and what lies under the water (section Caustics, on by default).
Stronger normals and the particle lighting now also reach materials the game loads during play (locations, dungeons, texture mods); before, only a settings change picked them up.
Caustics cost nothing where they cannot show: in dungeons, high above the sea and without light.
With the water settings off, or ValheimWater drawing the sea, the mod no longer goes on changing the water's detail distance.
Caustics fade under the moon, under clouds and in cloud shadows instead of shining as in full sun.
No more empty squares in the sea at the edge of the loaded area: near and far water now meet where the loaded water ends.
Reflections follow the scene within about a second instead of up to six (Reflections.RefreshSeconds).
Caustics follow the waves: no more caustics on sand a wave has left dry.
Settings window tidied: grouped and ordered, the main switches first, fine-tuning after them.
New "AO even far": ambient occlusion no longer darkens the distance more than the foreground (off by default, to try).
Contact shadows and GTAO ambient occlusion are on by default (a fraction of a millisecond on the GPU).
The Preset setting is gone (Off/Physical repeated Enabled). The Right Arrow key is now "Compare key": the game's own look and back, for this session. A config with Preset = Off keeps the mod off through Enabled.

Optional screen-space lighting, each off by default: ContactShadows (short sun shadows written into the game's own sun shadows), Gtao (ambient occlusion of the sky light only, with thickness so thin things cast no halo; replaces the post-processing occlusion while on) and IndirectLight (one bounce of light between surfaces on screen).
With AugaLite installed, the post-processing (antialiasing, ambient occlusion, vignette, reflections) and the depth of field values were lost at the first portal trip or dungeon entrance, and switching the mod off and on did not bring them back. AugaLite's teleport screen copies the game camera for its portal animation, and the copy took over the game's record of which camera has the effects; the mod followed it to the hidden copy and gave the real view back the game's own profile. The mod now finds the camera through the game camera itself.
The water settings stand down while ValheimWater (a separate mod: a new sea surface and caustics) draws the water.
Fixed a dark ragged band along the sea's horizon: the water detail distance (400 m) moved only the waves, while the game's flat far sea still started at 120 m, covered every trough in between and left the crests sticking out of it. The far sea now starts where the waves end, and the distance is capped at 350 m (about as far as the zones that carry the waves are loaded; the default is now 350).

Optional TAA jitter spread and vignette controls, including an explicit vignette Off mode.
Separate explicit switches to disable SSR and environment reflections, with reversible probe/sky suppression.
Custom internal render scale from 25 to 100%, plus bilinear, pixelated and Catmull–Rom bicubic upscaling.
Optional global LOD bias and a separate multiplier for loaded tree LODs. Both leave the game's settings alone by default.
Preserve later external changes when releasing settings. Yield if another mod replaces the post-processing profile, and restore current graphics choices after changing the game's settings while overrides are active.
Correct AO descriptions: current defaults use Medium samples with downsampling; the depth path still requests DepthNormals.
Mountain snow no longer breaks into small patches of shimmering noise. The game's terrain shader decides snow or rock per pixel from a biome weight that GPU rounding leaves at either 0 or 0.0000001, so neighbouring pixels flip between the two and reshuffle every frame. Surfaces.FixSnowSpeckle (on) lifts the terrain's biome colours by 0.01% so the weight cannot cross zero; the shader and textures are untouched.
With WeatherOverhaul installed, the water and reflection modules stand down wherever WeatherOverhaul declares it owns the water surface or the reflection probes, and come back when it stops. Without it, nothing changes.

Screen space reflections are now off, existing configs included: they cost the most FPS and could stutter, for almost no visible change. PostFx.SsrEnabled turns them back on.

The Thunderstore package depended on BepInExPack_Valheim 5.4.2202, which predates the pack's fixes for the game's Unity 6 (5.4.2333 and later), so a new mod manager profile could get that old pack. It now depends on 5.4.2351. Nothing changes in the game.
README: where to report problems.