The utility ``vrtest'' helps you verify that all the parts of a Syzygy installation are operating correctly -- an end-to-end test, from the user's actions all the way through to what they hear and see. When diagnosing misbehavior in a Syzygy application, a few seconds running vrtest will greatly narrow down the fault.
This application was called ``cubevars'' for several years. That name alluded to its inspiration, the early 1990's IRIX CaveLib program ``cavevars.'' Cubevars departed from cavevars in abandoning numerical displays for purely graphical ones.
Some of the graphics in vrtest deliberately hearken to those of the Input Simulator.
The large white wireframe cube indicates a cave-sized space, ten feet on a side. The origin is in the middle of the floor, in the usual cave coordinate frame.
On each wall of this cube, you'll see some text and a stylized pair of eyeglasses. The text label indicates which wall it is (front, right, ceiling, etc.). The eyeglasses indicate monoscopic or stereoscopic vision. If both lenses are visible, the display is monoscopic. If the display is stereo, when you close one of your eyes, the corresponding lens of the eyeglasses should vanish. (If it doesn't, that indicates a problem with your LCD shutter glasses, the shutter-glasses sync pulse, or (in a passive-stereo display) the polarizers.
The user's head appears as a yellow ball with cyan eyes and red pupils.
An indigo wireframe box is attached to the user's gaze vector (stuck in front of your nose). If you aren't always looking directly into the end of the box, head tracking is malfunctioning.
The wand is a long wireframe cone, magenta in color. The cone's point indicates the wand's ``forward'' direction. The wand's position is where the cone meets a cyan crosshairs. One of the crosshairs is longer and ends in a white wireframe ball; this indicates the wand's ``up'' vector.
Multiple wands will be drawn, if the virtual computer's definition includes them. Any 6DOF-tracked item (``matrix'') other than the first, which is the head, is considered to be a wand.
Near the wand, all of its buttons and ``axes'' (joysticks and sliders) are drawn.
The buttons are dark red cubes. When you push a button, its corresponding cube becomes larger and turns pale green.
The axes are green cubes on brown vertical sliders. The first two axes are redundantly drawn as a single cube in a square, since these axes usually correspond to a single x-y joystick on the wand.
On the front wall, three dark blue squares show views of the white wireframe cube from above, from the left, and from behind. This is as if you tilted your head down to look at the floor, or turned left to face the left wall, or simply stayed put and looked at the front wall.
These projected views help you visualize where the head and wand really are in the cube, particularly when tracking is malfunctioning and, e.g., the head is near the floor as shown here, or even several feet underground.
If the virtual computer's SoundRender program is running and the audio hardware is working, you hear a short sound whenever you depress or release a button. Also, as you wave the wand around, you hear a quiet rumbling whose loudness varies with the speed of the tip of the purple cone.