Calibrating playspace - ju1ce/April-Tag-VR-FullBody-Tracker GitHub Wiki

At first, the trackers will be in the floor. You need to calibrate playspace in order to use them in games. Do this by checking the Calibration mode checkbox.

A camera should now appear in SteamVR, and six fields should appear in the program.

Note: There is currently a but in 0.7 versions which causes the camera to spawn on the ground, in the center of the playspace. This means that it will be invisible, as it will render behind the square thing on the floor, but it is there, you can still grab it and move it higher to make it visible.

To see how calibration looks like, you can also check the full setup video here, which contains playspace calibration as well.

Cant see the camera or trackers?

• The camera is only visible in the empty SteamVR space thing, so make sure that you exit SteamVR home or camera wont show up.
• Make sure that you pressed 6. Start on the ApriltagTrackers window to actualy start detection, only connecting will not make camera and trackers appear.
• SteamVR, for some reason, renders the camera behind everything, even the square on the floor. What this means is that the camera can often appear invisible when it is in front of that square. You can usualy continue normaly with calibration, just move the camera a bit higher (you can grab the camera even if you do not see where it is, or you can set the position manualy to somewhere where you know you can see it (for example, X:0 Y:200 Z:0 will place the camera in the center of the playspace, 2 meters above the floor, where it should be clearly visible))

Calibration with controllers

To calibrate your playspace, you have to align the camera in SteamVR with your camera IRL. To do this, you can grab the camera by pressing the trigger on your left controller. Move the camera to its place, then press trigger again to drop it.

When camera is in position, you must also rotate it so the trackers in SteamVR will align with your trackers IRL. You can do this by pressing grip on your left controller. You can then move the trackers into their correct positions, and press grip again to drop them.

When you are done, uncheck Calibration mode to save!

Manual calibration

While not recomended as it is much harder than doing it with controllers, you can still calibrate by changing the values in the program directly.

Use the first three field to align the SteamVR cameras position with your camera position IRL. You can move the values using your thumbstick. To get the position accurately, its best to place one of your controllers next to the camera and use it as reference.

When you allign position, use the next three values to align rotation. When camera is coarsly alligned, step in front of the camera so the trackers can be seen. You can now do some finer adjustmets to the camera rotation, untill the SteamVR pucks will allign nicely with your tracker IRL - the puck should lay flat on one side of the tracker. You can, again, help yourself with a controller.

When you are done, uncheck Calibration mode to save!