ARFX Multiscreen Components

Section 2. ARFX Camera Components

Since the Multiscreen Camera is a variant of the ARFX Camera, all components are exactly the same.

An important aspect of all ARFX Cameras and Virtual Production in general, is the Component list. Found within the Details panel when you select any actor, the component list of any given actor in Unreal Engine contains everything that makes up the actor you see represented in the Viewport. Be it a static mesh, light, or even our cameras, everything is derived from this list.

1. Navigate to the Details panel for the newly added ARwallCameraActor. If this panel is not active, please enable it by going to the Windows menu and selecting Details.

2. Select the ARwallCameraActor within the Outliner.

3. Navigate to the Details panel and click the big green button ‘+Add Component’ in UE4 or the ‘+Add’ in UE5 dropdown.

4. Type in ARwall and select the ARwallTrackingComponentSteamVR. The ARwallCameraActor object should appear in the World Outliner window.

Important

By default, the component list in the details panel is really small. You can expand the list by mousing over its bottom edge until your mouse turns into an expansion icon for you to then size it to your needs.

ARFX Camera’s component list. There is a lot here but there is not much to actually do.

Important

This cannot be stressed enough: Do not edit any of the default components of the ARFX Camera unless you know what you are doing.

Every component in the default list serves a purpose when it comes to orientation and tracking. If you do accidentally change these components, an easy fix is to simply delete the camera and place a fresh one in its place. Since settings like screen dimensions and tracker serials are saved and shared across all actors regardless of scene you will not be losing much in doing so.

The Single Exception – Offset Component

The Offset Component, nested above the Camera Component, is generally never used but it does serve a purpose. Depending on the physical setup of your tracking device and how it is attached to your physical camera, the position of said tracker may be far away from where the camera’s sensor is located. Sometimes that difference in location can be significant enough to cause oddities such as height extremes when tilting up or down or simply that the background is simply off to the left or right.

The fix for that is this offset component. You must measure the distance between the tracker’s origin point and the camera sensor’s center precisely in centimeters then translate those values into the components’ position values.

The positions found here for the offset component determine tracker offset.

Note the orientation. DO NOT CHANGE THIS.

But which values go into which entry? The following image can help you figure this out:

The orientation may seem weird if you know Unreal or typical Euler orientations, but there are reasons for this.

Let us try a real-world example. On our camera we have our VIVE Tracker almost aligned with the sensor, but not perfectly. Measuring it we found it to be 16 cm above and 1 cm behind the sensor.

We find that most camera sensor’s depth is often represented by the focus puller hook. So if you can, use this to measure how far back or forward your tracker is.

With these values, we can input them into our offset as seen in the image below.

Important

Again, DO NOT change the rotation, just the position!