A new tool has been added to procedurally place objects in your scenes. It is completely independent from the terrain system and supports both prefabs and instanced models. 

It can be used to automate tasks such as procedurally generating landscapes, painting enemies, or even acting as a world grid system. 

We've added a new resource that defines a palette of objects, a scattering algorithm, and world partition settings.   

Entries
You can drag and drop prefabs or models into a palette. Each entry has its own weight to control the balance between assets. 

Scatterer
 You can choose from a list of scatterers, which can be extended by defining your own. Each scatterer can expose various settings to tweak object placement. A few are provided by default (Simple, Slope based, and Terrain based). 

You can create your own by inheriting from the Scatterer class and overriding a single method. 

List<ClutterInstance> Generate( BBox bounds, ClutterDefinition clutter, Scene scene )
{
    // return a list of clutter instances
}

Streaming
Infinite scattering is supported by dividing the world into tiles, which you can configure directly on the clutter resource. Larger clutter typically needs bigger tiles than smaller clutter items. 

As you edit these settings, the changes should be visible instantly in your scene, making the iteration process very fast and interactive. 

This component supports two mode:
Volume: Will execute over a fixed volume

Infinite: Will procedurally execute around the camera as it moves in the world. Generation uses a deterministic seed using tile coordinates.

 A new scene tool lets you paint clutter resources with a brush. It uses the scatterer algorithm, allowing you to create dynamic brushes. Like one that reacts to the underlying terrain, or nearby structure. You can define those rules by implementing your own scatterer.

A lot of prerequisites were needed to implement this tool but overall I'm really happy with where it currently sits in our toolset. It solves a bunch of problem and it's flexible enough that allows people to customize it to fit their needs.

We're polishing the menu ready for release, nothing is significantly different but we're making it all look pretty.

The depressing dark foggy scene is gone and replaced with Flatgrass. The header bar has been spaced out and made transparent. And the latest update is display on the front page.

We'll keep polishing stuff bit by bit each week.

We used to render UI trees as we were traversing it. This approach works but it didn't give use the flexibility we needed to optimize further. 

We now perform the UI rendering in two passes. 

First we build a list of GPU commands as we traverse the UI. Then, we execute that command list and render it. 
This allows us to perform a multitude of different optimizations.

The first is caching. Panels that haven’t changed don’t rebuild their command list anymore. That saves us from re-traversing large parts of the UI every frame.

It also opens the door for batching later on which will group together similar draw calls reducing GPU load.

We've added better support for drag & drop this week, trying to follow how it's done on the web.

UI could only render on the main thread - now it can render on any thread thanks to command lists. This means whilst your game is rendering the 3D world it can also start rendering the UI layers.

You'll notice a performance boost mostly on low-mid range CPUs and in games with a considerable amount of UI and 3D at the same time.

It can be toggled with the convar r_ui_multithreaded to measure impact.

I've added the CSS feature outline. Outline is a line outside of a panel's border. Outlines don't take up space, so they don't affect the layout of the document in any way.

These can render alongside borders, but are most notably used to outline textboxes when focusing them on the web without affecting layout.

In this example blue is outline, red is border, both are 10px thick. You can see outline does not bloat the container.

We reorganized the timings so they now more accurately break down the time needed to render a frame. Garbage collection pauses are now also tracked as individual timings, and subtracted from other timing scopes.

We also improved the visuals for various overlays with significant community contributions from @darkfated.

Last week, we improved incremental compiles and processing for .cs files. This week, we've extended those concepts to Razor files too.

Previously, every Razor file was reparsed and reprocessed from scratch every time you recompiled. Now, we reuse what we can. If your project makes heavy use of Razor, you should notice recompile times are much faster, regardless of whether the changes were in Razor files or not.

This is another step from us toward shrinking iteration times in your projects. The goal is for this to be as quick as possible, and we think we can get it even faster.

We use a clustered culling technique where lights, envmaps and decals are grouped into clusters which is later queried when rendered. We were getting some bad artifacting occassionally on various GPUs, the cause of this was cluster boundary instability.

On the left you can see on the boundaries of the quad there is a lot of noise where it can't decide which cluster it belongs to - this would create visual artifacts. On the right we've switched to deriving the cluster from screen position, this gives us stable cluster selection.

This resolves the artifacts.

The mirror tool in mapping mode only mirrored meshes, now they can mirror all selected objects.

The inventory got rebuilt to be slot based. You can drag and drop stuff from the spawnmenu right into your inventory. It's kinda cool.

The scoreboard and HUD got a new lick of paint. You can also mute people.

Brought up the weld tool to gmod parity by adding the ability to rotate after easy welding.

We also added a screen to the physgun that spits out info based on what you're doing with it. 

The Clutter system has been a long time coming, we wanted something that wasn't restricted to terrain and could be freely used in maps — I think we hit a really good balance here and it unlocks a lot of potential for games.

We've been polishing the editor a lot and now the main menu is getting the same treatment, as the central part of the game and platform it feels like it's bringing it all together.

We've really been hacking away at optimizations; UI has always been a pain point and shifting it to command lists and multi-threading it is a big step forward; we've been drastically reducing allocations and continue to do so making less garbage meaning less hitches; as well as a lot of micro-optimizations that continue to add up week after week. And finally improving our overlays to better show and diagnose problems.

Our crash rates have been stabilizing around 1-2% with less and less crashes every week.

And finally we continue to push on with Sandbox features as well as experimenting with what we can do differently to Garry's Mod.

Everything continues to move at a nice steady pace, focusing on the right things and bringing it all together.