Migrating to MRTK2: Changing viewpoint rotation angle when pushing the thumbstick

Intro

A short one, but one that took me quite some time to find.

If you are using MRTK2 to build a Mixed Reality app to run on Immersive Headsets - or at least an environment where you control the environment using controllers - you can typically 'teleport' forward and backward by pushing the thumbstick forward and backward, and rotate the view by pushing it left and right. Your viewpoint rotates either 90° left or 90° right (and of course you can change the view by rotating your head, but that's not the point). But what if you want to rotate only 45°? Or 22.5°?

I have spent quite some time looking in the MRKT2 config profiles looking for the rotation angle. The reason I could not find it, is because it's not there. At least, not directly. It's in the pointer - the 3D cursor, if you like. Yeah, you read that right.

First, we clone

Starting from a default MRKT2 project, we follow the following steps:

• Clone the Toolkit Configuration Profile itself. I used DefaultMixedRealityToolkitConfigurationProfile to start this time.
• Under Input, clone the Mixed Reality Input System Profile
• Under Pointers, clone the Mixed Reality Input Pointer Profile

Finding the right pointer

If you expand the Pointers section and then the Pointer Options sections, you will see a whole lot of pointers. The second one is the one we are looking for: ParabolicPointer. It's a prefab.

If you click it, it will open the asset folder Assets/MRTK/SDK/Features/UX/Prefabs/Pointers and highlight the prefab we just selected:

Finding the angle

Press CTRL+D to duplicate the pointer, then drag it the Prefabs folder inside your app:

 

If that folder is not there yet, create it first. Once the prefab is inside the folder, rename it to something recognizable - ParabolicPointer45 for instance. When you are done renaming you have automatically selected the pointer itself. Go over to the inspector, scroll all the way down to the "Parabolic Teleport Pointer" script and there, in the "Teleport Pointer Settings" section, you will finally see where that bloody 90° comes from:

Adapting and applying

So now it's simply a matter of changing the angle to what you want, so for instance 45°. Then you go back to your adapted Mixed Reality Input Pointer Profile and drag your customized point in the right place:

and now your view will only rotate 45° in stead of 90° when you push the thumb stick sideways.

Conclusion

I certainly did not expect this setting being contained in a pointer, as by now I am quite conditioned to look in configuration profiles by now. I was - incorrectly - assuming it would be somewhere in the camera or controller settings. It took me quite some searching and debug breakpoints to find out where things where happening, and I took a few blind alleys before I found the right one. Typically something I blog about so a) I can now easily find back how I did it and b) you now also know where to look for.

Demo project, although it does not do very much, here. When you run it (either from Unity or as an app) in your Immersive Headset, you will see a green 'floor' rotating only 45° when you push the thumbstick stick left or right.

Fixing the "Windows Mixed Reality specific camera code has been moved..." message when upgrading the MRKT2

A very short and very simple trick today:

If you - like me - are crazy enough to dutifully update the MRTK2 in your apps whenever a new version arrives, at some point you will notice a kind of puzzling, rather ominous and not very helpful message pop up in your console a couple of times:

"Windows Mixed Reality specific camera code has been moved into Windows Mixed Reality Camera Settings. Please ensure you have this added under your Camera System's Settings Providers, as this deprecated code path may be removed in a future update."

You might have seen this appear earlier, when you upgraded to MRTK 2.3, as you can see in this commit message. Version 2.3 was where it was introduced, in November 2019. The trouble with this message is that the procedure to fix it is not entirely clear - at least, it was not to me. Especially since the first warning originates from the MRTK2 itself (when the MixedRealityCameraSystem is initialized as a service). Also GoogleBinging it yields no result, but I do hope it does so after I post this article. Fortunately it was also originating from my own code, and that was a lot more helpful, as I know what that is about - I wrote it myself, after all.

The culprit was this piece of code:

CoreServices.CameraSystem.IsOpaque

This ends up in Microsoft.MixedReality.Toolkit.CameraSystem.MixedRealityCameraSystem where the IsOpaque property is implemented. That looks for a "IMixedRealityCameraSettingsProvider". That does not help much, but wat does help - in MixedRealityCameraSystem  there is a documentation link on top, which at least points you to the right place in the configuration.

So what you need to do is very simple and takes 7 mouse clicks:

1. Select the MixedRealityToolkit node in your hierarchy
2. Select the Camera Tab
3. Expand the Camera Settings Provider

You will now see this:

Then:

4. Click the "+ Add Camera Settings Provider" button just above "Display Settings"
5. Expand the "New data provider 0" section"

6. For "Type", select Microsoft.MixedReality.Toolkit.WindowsMixedReality/WindowsMixedRealityCameraSettings (this is actually two mouse clicks)

The end result should look like this:

.... and you are done. Unless you need to tweak the settings of the default camera settings profile, in which case you have to do the clone-and-adapt dance. But in any case, no more scary messages about deprecated code that might change in some future release. ;)

I omitted the customary demo project this time, as the point of this post was to show you how to get from A to B, not the end result.