Update: ProBuilder is now part of the Unity team and completely free. I highly recommend checking it out now. (Not that SabreCSG isn’t great, but the tool is less attractive now that ProBuilder is also free.

Before I get started, I want to make one thing clear – I am not an artist. I’ve never been able to get the hang of the complexity of working in Blender or other popular 3d tools, and the pipeline of building, UV unwrapping, texturing, importing, etc can be frustrating when all you want is something functional you can work with. If you’re just looking for a tool to do basic level designing and prototyping and your budget is exactly $Nada then look no further – SabreCSG is for you. Why’s that? Oh, because it’s free, open source, and actually a really solid tool.

SabreCSG uses a type of modeling called Constructive Solid Geometry (CSG) based around using additive and subtractive simple geometry to create a more complex model. As a package SabreCSG offers individual face and vertex resizing, vertex welding, .OBJ export, among others. Overall though, the reason I’m going to keep this review short, and the reason that you should consider this if both free and easy appeal to you – it has amazing documentation and tutorials. Seriously, go look at their page for a second.


Quite a few developers don’t like being restricted to a few primitives – it’s quite annoying to have to launch another program to create a basic staircase for example. It should come as no surprise that SabreCSG isn’t the only attempt to get prototyping and modeling work into Unity. There are a few competitors at different price ranges and quality levels. Below is a short description of these competitors differentiators, their Unity asset store rating, and other useful details (from least to most expensive):

  • ProBuilder Basic – Free! – 5/5 Stars- Unity 5.0 or higher

    If there was a standard CSG tool, ProBuilder is probably it. In addition to their advanced asset (below) there is a completely free to use CSG solution available from them – but you lose a few features SabreCSG has to offer – primarily the ability to do per-face texturing.

  • CSG – $15 – Not Enough Ratings – Unity 5.5 or higher

    CSG boasts quite a few of the same features as SabreCSG with the addition of run-time usage via the editor or scripting.

  • Realtime CSG – $49 – 4/5 Stars – Unity 5.4.5 or higher

    Realtime CSG adds a few handy features like brush support, FBX export, and complex curve shapes. It also contains tools for additive and subtraction building and material application – similar to the core functionality of SabreCSG.

  • ProBuilder Advanced $95 $66.50 (on sale at posting) – 5/5 – Unity 4.7 or higher

    ProBuilder Advanced is easily the tool of choice for quick model editing if you don’t mind the cost. It has all the features you could want, professional support, and is used in quite a few published games already.

  • Archimatix– $145 – 5/5 – Unity 5.3.4 or higher

    Archimatix is the new kid on the block for in-editor modeling and takes a bit of a different approach – node based model generation. The asset is worth a look even if you are currently using one of the other tools as it builds off existing 3D models.

SabreCSG Interface & Features

The interface is very straightforward and similar to how things typically work in Unity. The controls are split into the top and bottom control areas. The bottom area allows you to quickly create a few standard brushes and contains some useful information and settings. It also contains the “Rebuild” button which transforms the brushes into the finalized model:

The top menu is a bit more complicated, and contains the following different controls:

  • Resize
    • The resize menu contains bound resizing (by face and vertex), Unity style transform and rotation tools.
    • Additionally contains options to snap center and flip the selected brush on the X, Y, and/or Z axis.
  • Vertex
    • Selecting individual corners allows for vertex manipulation within the brush.
    • Allows you to connect points on individual brushes logically, allowing finer control using the other tools.
    • Welding options to combine multiple vertices into one – useful for turning a cube into a pyramid for example.
  • Face
    • Allows you to modify UV data for individual faces, and apply separate materials.
    • Also includes several helpful face selection tools so you don’t have to click each one manually.
  • Clip
    • Used to draw a plane for splitting or culling individual brushes along the plane.
  • Draw
    • Draw a 2D shape, double click, drag to the desired 3D size and viola – you have a custom shaped brush without modifying any vertices!


Overall, SabreCSG has onefeature above others that make it attractive to me – it’s incredibly easy to use even if you aren’t an artist. It does have a few drawbacks and limitations (ie: a lack of symmetry tools), but it’s hard to argue with the features and ease of use for a free product.

SabreCSG Level Design Tools
 4.7/5 (Hey, it’s hard to argue with free.)