Aligning HMDs with outside-in systems
Last updated
Last updated
This section outlines the process for aligning Head-Mounted Displays (HMDs) within your project environment, ensuring precise tracking and interaction within the virtual space. Proper alignment is crucial for a seamless and immersive VR experience.
Follow these steps to align HMDs for each player in your project.
Alignment is done through the Alignment tab of the inspection panel. But before you begin you will need an alignment tool that fits your headset.
Existent supplies alignment tool for the specified HMD/tracking system. You can also follow the instructions to download and 3D-print the alignment tool yourself.
The alignment tool will need to be set as a trackable object in whichever tracking system you are using.
Select the Trackers tab in the existent inspection window.
Select the previously setup alignment tool tracker as the HMDReference tracker as shown below.
Now select the Alignment tab in the inspection window (See screenshot below).
Attach the alignment tool to your headset.
Use the “Align” button to initiate the alignment process.
Immediately start moving the headset in a smooth figure of eight pattern. The alignment process will continue until enough samples have been collected.
Once the alignment is complete the headset will automatically be aligned to the new values. Put the headset on and check that you are happy with the result. If you are not happy try running the alignment procedure again.
Once you are happy with the alignment type a name to identify the values in the box to the right of “Save Alignment To” and then hit save. The new alignment will now be saved and also set to be the default alignment.
Persisting Alignment Values:
The alignment values are stored in an Existent.ini file in the projects Saved/Config directory. The file will contain all the save alignment values. You can swap between them using the Select Alignment Preset drop down on the alignment tab. Changing the alignment using this drop down will also make the selected value become the default.
Replicating Alignment Across All Players:
The recommended method to share alignments across multiple machines for multiplayer is to copy the Existent.ini file to each machine. Headsets in LBE mode that use the same map will use the same alignment so there is no need to align each headset individually.
By following these detailed instructions, developers can ensure that all HMDs used in the project are accurately aligned with the virtual environment, enhancing the overall user experience. Proper alignment is key to achieving precise tracking, interaction, and immersion within Unreal Engine-based VR projects.
