Tag Archives: Unity3D

HoloLens and MR Device Dev Advisory Mar-2018

I’m currently doing HoloLens development with VS 2017 v15.6.4, Unity 2017.3.1p3, MRTK 2017.1.2, and W10 17128 (Insider Build).

Unity 2017.3.1p3, a patch release, includes the 2017.3.1p1 fix for hologram instability:

(993880) – XR: Fixed stabilization plane not getting set correctly via the SetFocusPointForFrame() API, resulting in poor hologram stabilization and color separation on HoloLens.

There continues to be uncertainty about whether this fixes all the stabilization problems or not – though it’s definitely better than it has been over the past several months.

UnityWebRequest continues to always return true for the isNetworkError property. Use isError or isHttpError instead. The older WWW class probably shouldn’t be used anymore. There are reports that media downloads aren’t working with UnityWebRequest while other file types are.

So if you have something working now, and have work-arounds in place, you probably shouldn’t upgrade. I know of HoloLens developers who are still very happy working in the older Unity 5.6.3.

April is shaping up to be very interesting. According to Unity, they will be releasing Unity 2018.1.0 then. For UWP/HoloLens developers, this means the addition of the .NET Standard 2.0 API compatibility level. .NET Standard 2.0 can be thought of as the set of APIs commonly supported by both .NET Core 2.0 (what UWP uses) and .NET Framework 4.6.1 (used for Windows apps and in the IDE). By supporting this, Unity 2018.1.0 should provide us with the ability to write much more common MonoBehaviour script code that works in both the IDE and on the HoloLens without using precompiler directives.

Of course, this is only useful if the HoloLens actually supports .NET Core 2.0, which is why the announcement of the RS4 Technical Preview is such a big deal. This is the first major firmware update for the HoloLens since release, and brings with it all the changes to Windows platform since the Anniversary Update (build 10.0.14393) which was also known as RS1 and which supports .NET Core 1.0.

Redstone 4 (build 10.0.17133), also known as the Spring Creators Update, is supposed to drop for PCs in mid-April. Which coincidentally is also when Unity 2018.1.0 is supposed to drop. So it would not be out of the question to expect a version of RS4 for HoloLens to drop at around the same time.

What sets RS4 for HoloLens apart from RS4 for Windows? For one thing, on the HoloLens we will have access to a new feature called Research Mode, providing access to low level sensor data such as the ToF depth camera and potentially the 4 mono cameras and the microphones. This in turn can be used to try out new algorithms beyond what the HoloLens already currently uses for data analysis.

On the UI front, the MR Design Labs interface tools have finally been integrated into the dev branch of the Mixed Reality Toolkit. Fingers crossed that this will make its way into the main branch in April also.

Finally, Magic Leap’s mixed reality headset, dubbed the Magic Leap One, had its debut at GDC this month. They also opened their creator portal to all developers, with links to documentation, the Lumin SDK, a special version of Unity 2018 to develop ML apps and a simulator to test gesture and controller interactions.

In the interest of full disclosure, I’ve been developing for the Magic Leap for a while under NDAs and inside a locked room ensorcelled by eldritch spells. It’s a great device and finally creates some good competition for the HoloLens team at Microsoft.

The first reaction among people working with the HoloLens and occluded MR devices may be to be defensive and tribal. Please resist this instinct.

A second, well-funded device like the Magic Leap One means all that much more marketing dollars from both Microsoft and Magic Leap spent on raising the profile of Mixed Reality (or Spatial Computing, as ML is calling it). It means healthy competition between the two device makers that will encourage both companies to improve their tech in efforts to grow and hold large swaths of the AR market. It also means a new device to which most of your spatial development skills will easily transfer. In other words, this is a good thing my MR homies. Embrace it.

And from the development side, there are lots of things to like about Magic Leap. Lumin is Linux/Mono based, which means a higher level of compatibility between the platform and pre-existing Unity assets from the Asset store. It also supports development in Unreal. Lastly, it also supports development on a Mac, potentially offering a way for crossover between the design, gaming and enterprise dev worlds. This in turn raises interest in high-end AR and will make people take a second look at HoloLens and the occluded MR devices.

It doesn’t take a weatherman to know it’s going to be a great summer for Mixed Reality / Spatial Computing developers.

Windows Insider Builds and Unity Licenses

On one of my dev PCs, I’m on the Windows 10 Insider Builds inner ring, which updates my computer with intermediate builds of Windows. This gives me access to the latest features for testing. Unfortunately, it also means that my Unity Plus license goes into an inconsistent state every few weeks after an Insider Build changes my computer profile enough that Unity no longer recognizes it as the same computer.


In the past I’ve tied going into my account management and try to revoke the assigned seat and then assign it again to myself. Sometimes this works but often it doesn’t. Somehow during the Windows update process, something happens with the original license that it cannot be disabled correctly.



I recently found out that there is a different route to deactivating seats that will work even after a Windows 10 update. Back in the account landing page, you need to navigate to My Seats instead of going through the Organizations menu.





This leads you to a page that lets you remove all license activations. Once you’ve clicked on “Remove all my activations”, you can then successfully use your license key to reactivate your Unity IDE.

HoloLens App Development with Unity

A few months ago I wrote a speculative piece about how HoloLens might work with XAML frameworks based on the sample applications Microsoft had been showing.

Even though Microsoft has still released scant information about integration with 3D platforms, I believe I can provide a fairly accurate walkthrough of how HoloLens development will occur for Unity3D. In fact, assuming I am correct, you can begin developing games and applications today and be in a position to release a HoloLens experience shortly after the hardware becomes available.

To be clear, though, this is just speculative and I have no insider information about the final product that I can talk about. This is just what makes sense based on publicly available information regarding HoloLens.

Unity3D integration with third party tools such as Kinect and Oculus Rift occurs through plugins. The Kinect 2 plugin can be somewhat complex as it introduces components that are unique to the Kinect’s capabilities.

The eventual HoloLens plugin, on the other hand, will likely be relatively simple since it will almost certainly be based on a pre-existing component called the FPSController (in Unity 5.1 which is currently the latest).

To prepare for HoloLens, you should start by building your experience with Unity 5.1 and the FPSController component. Here’s a quick rundown of how to do this.

Start by installing the totally free Unity 5.1 tools: http://unity3d.com/get-unity/download?ref=personal


Next, create a new project and select 3D for the project type.


Click the button for adding asset packages and select Characters. This will give you access to the FPSController. Click done and continue. The IDE will now open with an practically empty project.


At this point, a good Unity3D tutorial will typically show you how to create an environment. We’re going to take a shortcut, however, and just get a free one from the Asset Store. Hit Ctrl+9 to open the Asset Store from inside your IDE. You may need to sign in with your Unity account. Select the 3D Models | Environments menu option on the right and pick a pre-built environment to download. There are plenty of great free ones to choose from. For this walkthrough, I’m going to use the Japanese Otaku City by Zenrin Co, Ltd.


After downloading is complete, you will be presented with an import dialog box. By default, all assets are selected. Click on Import.


Now that the environment you selected has been imported, go the the scenes folder in your project window and select a sample scene from the downloaded environment. This will open up the city or dungeon or forest or whatever environment you chose. It will also make all the different assets and components associated with the scene show up in your Hierarchy window. At this point, we want to add the first-person shooter controller into the scene. You do this by selecting the FPSController from the project window under Assets/Standard Assets/Characters/FirstPersonCharacter/Prefabs and dragging the FPSController into your Hierarchy pane.


This puts a visual representation of the FPS controller into your scene. Select the controller with your mouse and hit “F” to zoom in on it. You can see from the visual representation that the FPS controller is basically a collision field that can be moved with a keyboard or gamepad that additionally has a directional camera component and a sound component attached. The direction the camera faces ultimately become the view that players see when you start the game.


Here is another scene that uses the Decrepit Dungeon environment package by Prodigious Creations and the FPS controller. The top pane shows a design view while the bottom pane shows the gamer’s first-person view.


You can even start walking through the scene inside the IDE by simply selecting the blue play button at the top center of the IDE.

The way I imagine the HoloLens integration to work is that another version of FPS controller will be provided that replaces mouse controller input with gyroscope/magnetometer input as the player rotates her head. Additionally, the single camera view will be replaced with a two camera rig that sends two different, side-by-side feeds back to the HoloLens device. Finally, you should be able to see how all of this works directly in the IDE like so:


There is very good evidence that the HoloLens plugin will work something like I have outlined and will be approximately this easy. The training sessions at the Holographic Academy during /Build pretty much demonstrated this sort of toolchain. Moreover, this is how Unity3D currently integrates with virtual reality devices like Gear VR and Oculus Rift. In fact, the screen cap of the Unity IDE above is from an Oculus game I’ve been working on.

So what are you waiting for? You pretty much have everything you already need to start building complex HoloLens experiences. The integration itself, when it is ready, should be fairly trivial and much of the difficult programming will be taken care of for you.

I’m looking forward to seeing all the amazing experiences people are building for the HoloLens launch day. Together, we’ll change the future of personal computing!