The algorithms in the EyeX Controller and Engine software assumes the EyeX Controller has been attached to the computer monitor using the supplied mounting bracket (black metal bar with adhesive tape). Using this mounting bracket firmly attached on a surface parallell with the screen surface, the EyeX Controller sensors will have a certain known angle relative to the computer screen. This known angle is used during calibration and is needed to correctly map your eye-gaze to a point on the screen. If you use a wedge between the EyeX Controller and the screen, the mapping of you eye-gaze to the screen will be distorted in a way similar to the keystone effect one can se when tilting a video projector up or down when projecting an image on a screen.
Currently the EyeX Engine only supports this default angle, and we do not have a timeline for if or when a “multiple angle feature” could be implemented in the engine.
This is how you can find a good position of your eyes relative to the screen and the EyeX Controller:
1. Attach the EyeX Controller using the supplied mounting bracket and as shown in the instruction images that came with the device.
2. Sit down with the laptop in front of you.
3. Position yourself so that your eyes are at about an arm’s length distance from the EyeX Controller.
4. Tilt the laptop’s screen away or towards you until you see your own eyes reflection looking back on you on the front surface of the EyeX Controller.
Although this is a very good starting point for how you should position yourself, the EyeX Controller has a good tolerance for free head movement, so it is capable to keep tracking your eyes even if you lean to the sides or away from it a bit.
Hope this helps and clarifies some things.