17 December 2025

Update 25.12.17

Winter additions and a ton of mapping tools

matt, Jase, Danduw, Layla and 3 others 11 sections

Winter Main Menuby Jase

I made last week's winter scene into a new main menu that'll stay for the duration of the holiday season.

Scene flythrough

sbox-dev_AcntydaRfO.mp4 36.66 MB

We'll likely continue doing these with future holidays and special occasions.

Reindeer Setby Danduw

We've released our Christmas 2025 Outfit this month. Available till January 1st!

We've recently added the option of physics bones for cosmetics, this new outfit has been a great excuse to test it out.

christmas_wiggles.mp4 36.85 MB

Showcase of the outfit on the human character -

We're really getting into our stride with Holiday / Event cosmetics. As we move into next year, we'll be exploring more outfits that showcase new developments - physics bones, shaders and animated elements.

Edge Cut Toolby Layla

The mapping tool now has the edge cut tool. This allows you to quickly create edges on faces to do things like cut out doorways.

sbox-dev_M26bJq1slR.mp4 2.26 MB

Polygon Toolby Layla

The create primitive tool can create block primitives and now they can create polygons by drawing points.
You should also be able to extend this to create your own types of primitive editors. You want to create stairs by clicking two points in the scene? You can code that.

sbox-dev_B0CH84oxhi.mp4 2.41 MB

Resize Modeby Layla

A common tool used in map making is being able to resize your selection with a 6 handle box gizmo, you can now do that again.

sbox-dev_reVmtmcVlw.mp4 3.01 MB

Material Paletteby bakscratch

One thing to speed up mapping is having the ability to quickly switch to commonly used materials, We have that now as well as having different material palettes that you can switch between.

sbox-dev_dRhOIGw7tq.mp4 2.62 MB

Fast Texturing Toolby Carson

The Fast Texturing Tool that most know-and-love from Hammer has been implemented within the scene's Mapping Tools. This makes it super quick and easy to UV something by leveraging the existing Rect Editor.

15_08-21-CaringSkimmer.mp4 6.04 MB

3 Mapping Modes: Unwrap Square, Unwrap Planar, Use Existing
U/V Alignment and Horizontal/Vertical Flip settings
Inset X/Y Settings
Includes "Pick Edge" button which allows you to select an edge to orient the unwrapped UVs around
If the selected material is a hotspot material with defined rects, you can double click on a rect to automatically fit your UV rectangle to the one you double-clicked.
Tiled View

Rect Editor Changesby Carson

Made some various fixes/improvements to the Rect Editor while developing the Fast Texturing Tool. These changes affect both the Rect Editor and the Fast Texturing Tool

15_08-35-DraftyGlowworm.mp4 1.5 MB

Added Panning/Zooming
Resizing rects will now snap the dragged edge(s) to the grid properly
Disabling the Grid will disable Grid Snapping
Rectangles can be resized in on themselves without causing crashes/NREs

Networked Collection Callbacksby conna

This adds the following callbacks to NetList:

/// <summary>
/// Get notified when the list has changed.
/// </summary>
public Action<NetListChangeEvent<T>> OnChanged;

And the following to NetDictionary:

/// <summary>
/// Get notified when the dictionary is changed.
/// </summary>
public Action<NetDictionaryChangeEvent<TKey, TValue>> OnChanged;

Called for both the caller and the remote client that receives updates.

Buffered Descriptor Set Crashby matt

A really bad crash we've been suffering with this year is writing to buffered descriptor sets, this crash was quite frequent but hard to track down as it's hard to reproduce, manifested in different ways and rarely caught by our crash handler, the number of events / users affected below is a fraction of the ones occuring.

The crash would occur when a buffer was deleted whilst still referenced in the set, normally there is reference counting throughout the renderer, and there was for textures here but not buffers.

It turns out Valve were having similar crashes and had already solved it by adding reference counting to the buffers - we backported these and it's all resolved!

Christmas Breakby matt

Facepunch is going on Christmas break for 2 weeks, this will be the last update until January.

year in review

This year s&box has really found it's identity; we started the Play Fund that has paid out $260,000 to creators, we sold our first community cosmetics, we open sourced the engine, we've inched further to standalone games — s&box is all about giving back to the community that made us, providing opportunities for the next generation.

In 2024 we took a big risk and pivoted everything to the scene system, this redefined what s&box was, taking us beyond a glorified Half Life Alyx mod into a modern day engine. It unlocked everything for us, but also made us have to start again, rethinking everything.

Last year was a lot of broad strokes, exploratory work trying to find what we can be. This year was the hard work, bringing it all together, prioritizing what needs to be done, and putting the puzzle pieces back together.

what's next

Our current plan is to release in early 2026, we're happy with our feature set, we have the Sandbox game to finish and refining our features to get to 1.0. Our biggest pain point right now is still performance and stability, the new user crash reports has been helping to solve these, as well as users submitting profiles of their games - we're on it.

Release for us just means generally avaliable on Steam, we're still gonna be developing and delivering new features month after month, the same way we do with Garry's Mod and Rust - s&box is a multidecade project for us.

Thanks for following s&box, see you next year!