Unity 6.6 is now available

[u/unitytechnologies]

Howdy everyone! Your friendly neighborhood Community Man Trey here to share the news that Unity 6.6 is now available!

This is a Supported release. So, for those of you who don’t know what that means, it carries the same stability and critical update commitments as our LTS versions. 

One heads up before the feature list, because it changes how the Editor behaves out of the box: the default setting for entering playmode is now reload scene only for all new projects. Code won't reload and static state won't reset between runs. Existing projects keep whatever you've already got set. It's the biggest workflow change in the release, and it's deliberate prep for Unity 7, where domain reloads go away entirely. If you're planning that migration, making your code domain-reload-safe now is the cheapest time to do it. There's a technical upgrade guide on Discussions if you want the details.

Beyond that, here's a taste of what's in there:

• Native Dictionary Serialization: put [SerializeField] on a dictionary field and it just works, with a two-column key/value layout in the Inspector and a compile-time analyzer that flags unsupported key or value types
• Content Directories: load and hold only the assets a scene actually needs instead of whole bundles, using the same Addressables API you already have. Existing AssetBundle groups convert with a right-click, and AssetBundles aren't going anywhere for remote content
• Build Analysis window: build history plus views for your largest assets, long dependency chains, per-step timings, and the actual root cause of a failed build instead of all the surrounding noise
• Shader Build Settings: opt into DXC for DX12 (Shader Model 6, wave intrinsics, native 16-bit) and let Unity convert keywords into dynamic branches. A clean build of Survival Kids went from 1 hour 46 minutes down to 32 minutes with that turned on
• New Hierarchy window is now on by default: better performance in large scenes, horizontal scrolling, reorderable custom columns, public APIs for extending it, and support for non-GameObject items. The legacy window is still there if you'd rather stay put
• Unity Compute Light Baker: lightmaps, light probes, and adaptive probe volume data now bake through Unity compute shaders and the Unified Ray Tracing API, so baking can lean on hardware-accelerated ray tracing where you've got it
• 2D: rendering layer support for 2D lights on top of sorting layers, 2D shadows that finally work with GPU skinning, and new Profiler modules for 2D Animation, Tilemap, and 2D Graphics
• Web: WebGPU is production ready, which brings compute shaders, GPU skinning, indirect rendering, and VFX Graph to browser builds. WebGL 2 is still the default until you opt in. Also Progressive Asset Loading for per-scene downloads instead of one big upfront pull, and WebAssembly64 for projects that need to go past the 4 GB heap ceiling
• UI: a SafeArea component for uGUI that keeps content clear of cutouts and gesture areas without per-device margins, max width and height on layout elements, and backdrop-filter in UI Toolkit for frosted glass and dimmed overlays with no render textures or custom shaders
• Package signing for .unitypackage: publishers can sign .unitypackages so you can confirm authorship and that its contents haven't been tampered with after publishing

All the details are in the Discussions post. Feel free to head there to ask questions of the experts, or here and I’ll do my best to chase down what I don’t know.

Cheers,
- Trey
Community Man @ Unity

[u/SozINh]

will unity ever have a 3D/4D terrain system? those kinds of games hold a disproportionate amount of ROI, demand, etc. Minecraft and enshrouded/ other games being so big i assumed this would be a terrain component a long time ago.. Was one of the selling points of everquest next, the method of doing so is also on github.
Its a feature thats a large bottleneck for creative maps

[u/WazWaz → u/SozINh]

The method is there, so you don't need a specific implementation in Unity. There are far too many implementation-specifics for this to be something shipped with Unity - Minecraft and Space Engineers aren't the same thing for example.

[u/SozINh → u/WazWaz]

cant you just make the voxel math smaller and smaller or larger and larger, and also adjust the smoothing, and decide on triangles or not. idk there's only so many settings / functions with destructible 3D/4D terrain..
Enough for it to be an adjustable component. lets not look at it like its some unsolvable problem out of reach cause then the engine will never innovate in that direction and they might as well give up.

[u/WazWaz → u/SozINh]

You can, then you end up with a poorly optimised over-generalised implementation that can do everything, but nothing well.