Open Brush is a free fork of Tilt Brush, a room-scale 3D-painting virtual-reality application available from Google, originally developed by Skillman & Hackett. We have made a large number of changes from the original repository, including Unity upgrades and feature additions to bring Open Brush up to modern XR development standards. You can find the notable changes on our docs site.
We hope to maintain and improve upon Tilt Brush as a community-led project, free forever!
As the original repo is archived we cannot submit PRs, so feel free to submit them here!
User Guide
Developer Notes
Roadmap
Please join the Icosa Discord and get involved!
List of tutorials, write-ups and other things from the community
Support us on Open Collective
Instead of waiting for a formal release, you can download a ZIP from Github containing an automatically built release for either Windows (SteamVR) or Oculus Quest / Quest 2 from the Github releases page. Versions of the form "vX.Y.0" are official releases, whereas versions that do not end in .0 are made available for testing purposes only, with no guarantees as to their quality. Additionally, these releases are marked as "pre-release". However, if you'd like to test a recent change prior to the official release, you can use these either in place of or in parallel with the formal Open Brush releases.
These builds share a save location with the official Open Brush release, but can be installed alongside the formal version. The Oculus build, like all sideloaded content, will be listed in "Unknown Sources", and will have the word "Github" appended to the name (with a different package name as well) to differentiate it from the official release).
Note that the "experimental" builds contain experimental brushes, and sketches created using the experimental brushes may appear differently when loaded in the official build of Open Brush!
In addition, there is also a version created for Windows Monoscopic that is listed as an "Artifact" of the Github Actions, however, this is intended only for developers, and should not be used by general users. You can find it by browsing to the commit list, and then clicking on the green check mark below the title (next to the XXX committed XXX ago), and scroll to the build you want, and click on Details. Then, towards the upper right corner, click on Artifacts and click on the name of the build. Unzip the downloaded file, and either run the executable (Desktop OpenXR/Monoscopic) or install the apk (Android Oculus) using adb install com.Icosa.OpenBrush-github.apk
.
The Tilt Brush trademark and logo (“Tilt Brush Trademarks”) are trademarks of Google, and are treated separately from the copyright or patent license grants contained in the Apache-licensed Tilt Brush repositories on GitHub. Any use of the Tilt Brush Trademarks other than those permitted in these guidelines must be approved in advance.
For more information, read the Tilt Brush Brand Guidelines.
Get the Open Brush open-source application running on your own devices.
Support/bin
directory)
Tested with Python 3.8.Follow these steps when running the application for the first time:
/Assets/Scenes/Main.unity
. Unity should automatically prompt you to
import TextMesh Pro.These steps have been tested with Release 1.0.54.
Although it's possible to build Open Brush using the standard Unity build tools, we recommend using a build script to ensure the application builds with the correct settings. To run this script, go to Open Brush > Build > Do Build, or build from the Open Brush build window by navigating to Open Brush > Build > Build Window.
Note: The application may take a while to build the first time.
Use the build
script in the Support/bin
directory to specify the target
platform and the build options you wish to enable. Run build —help
to see the
various build options.
You should be able to get the basic version of Open Brush up and running very quickly. The following features will take a little more time.
Some systems in Tilt Brush were removed or replaced with alternatives due to open-source licensing issues. These are:
Credentials for services such as Google and Sketchfab are stored in a SecretsConfig
scriptable object. This has been ignored in the git config for safety. To add it back:
/Assets
folder in Unity's project window.
Select Create
, then Secrets Config
. This will create Secrets.asset
in the Asset folder.Scenes/Main.unity
go to App > Config and replace SecretsExample
with the newly generated Secrets.asset
.Set up Google API support to access Google services in the app.
Follow these steps when enabling Google service APIs:
Enable the following APIs and services:
Note: The name of your application on the developer console should match the
name you've given the app in App.kGoogleServicesAppName
in App.cs
.
Follow these steps when creating a Google API key:
The OAuth consent screen asks users for permission to access their Google account. You should be able to configure it from the Credentials screen.
Follow these steps when configuring the OAuth consent screen:
Add the following paths to the list of scopes:
../auth/drive.appdata
../auth/drive.file
The credential identifies the application to the Google servers. Follow these steps to create an OAuth credential:
Follow these steps to store the Google API Key and credential data:
Google
as the service. Paste in the API key, client ID, and client
secret that were generated earlier.Open Brush targets OpenXR instead of Oculus by default. Follow these steps to enable native Oculus support: .
OCULUS_SUPPORTED
and press Apply.Follow these steps to build your app for Oculus Quest:
../Builds/OculusMobile_Release_OpenBrush/
.adb install com.Icosa.OpenBrush.apk
.Note: Tilt Brush is a Google trademark. If you intend to publish a cloned version of the application, you are required to choose a different name to distinguish it from the official version.
Follow these steps to publish to Oculus stores:
Secrets
file. Both Oculus
and OculusMobile
should
have their own entries.Client ID
field for each.The Open Brush intro sketch uses some slightly modified shaders to produce the
animating-in effect while the sketch fades in. For faster loading, the intro
sketch is turned into a *.prefab
file beforehand. Only the shaders used in the
intro sketch have been converted to work with the introduction.
Support/Sketches/Intro
. There
are two versions, one for PC and one for mobile.*.prefab
files are located in Assets/Prefabs/Intro
.Assets/Materials/IntroMaterials
.Assets/PlatformConfigPC
and Assets/PlatformConfigMobile
files
reference the *.prefab
files that will be used in the intro.Follow these steps to replace or alter the intro sketch:
SceneParent/Main Canvas
. Select any of the Batch_...
objects to check whether they have
the intro materials set.Batch_
out from under the Main
Canvas node.*.prefab
file called gameobject_to_prefab
.
under the Assets/TestData
folder.Assets/Prefabs/Intro
folder.Assets/PlatformConfigPC
and
Assets/PlatformConfigMobile
to point to your new prefab file.You may want to have a pared-down version of the intro sketch for the mobile version of the app. Stroke simplification is located in the Settings menu inside Open Brush.
By default, your app will only build the scenes defined in the DoBuild method (string[] scenes = {...} ) in BuildTiltBrush.cs
under Assets/Editor/
. Make sure to add your custom scenes to this array if you want to see them in app.
Follow these steps to enable Sketchfab support:
Contact Sketchfab for a client ID and secret before you can upload to their service.
If you add video support, you may encounter a bug where the "Looking for audio" and "Play some music on your computer" text will disappear if the controller is angled too far. Fix this by doing the following:
/Assets/TextMesh Pro/Resources/Shaders/TMP_SDF.shader
file.TMP_SDF-WriteDepth.shader
.TextMeshPro/Distance Field
to
TextMeshPro/Distance Field Depth
.Zwrite Off
to Zwrite On
./Assets/Fonts/Oswald-Light SDF.asset
.Atlas & Material
, double click Oswald-Light SDF Material
.Shader
from TextMeshPro/Distance Field
to TextMeshPro/Distance Field Depth
.When the user records a video from a saved sketch in Open Brush, a .bat
file
is generated next to the .mp4
for offline rendering support. This .bat
file
requires the path to the executable of Open Brush. The code for writing out this
path to the file has been removed.
Follow these steps to restore the path:
Assets/Scripts/Rendering/VideoRecorderUtils.cs
in a code or
text editor.CreateOfflineRenderBatchFile
near the bottom of the
file.Experimental mode is where features live before they are ready to be released in a production build. This mode enables the experimental brushes and experimental panel while disabling the intro sequence. Experimental mode can be enabled from the settings panel, and requires a restart.
New features and brushes that you find in experimental mode may not work as expected. Sketches that use experimental features and brushes won't work on Icosa or Sketchfab, and may break if loaded into production versions of Open Brush.
Code in experimental mode is usually surrounded by the following block:
if (Config.IsExperimental) {
// Experimental code goes here
}
Experimental brushes and environments are located in the Assets/Resources/X
folder. They are not visible in non-experimental mode.