modern VR only has 3 points of articulation that are tracked in space -- the head, and each hand. This is why games like Half Life Alyx are just floating hands, no arms, because there are not enough points in space to actually simulate the arms.
In real life, the location of our limbs in space is determined, logically, as a series of weighted joints extending from our core frame. Our shoulder is one point, where it is resting in the real world influences our elbow, which influences our wrist, which influences our hands. Mapping from the core of our frame to the hands is known as kinematics.
In 2D games, there is a way to work backwards to simulate this, called inverse kinematics. Using a rigid body, you can guess where the preceeding joints
might be to figure out a logical position. So the position of your hands informs a guess where the elbow
might be, which informs where the shoulder
might be, and so forth. These guesses are almost always wrong, which is why games like Jurassic Park Tresspasser does things like this:
IK and VR do not play well together at all. When we worked on Half Life 2 VR, we used floating hands because we realized that the IK would cause the arms to actually swing in front of the players eyes during shootouts, blocking their view. And because the joints on the elbow and shoulder aren't actually tracked but rather inferred, the only way to move the arms out of your eyes was to move your hands, thus ruining the shot. So the solution was to just not map the arms at all, and concentrate on the known, well tracked limbs (i.e. hands alone).
Boneworks uses IK,
and applies a physics model to them. So your arm, which is just inferred by your hand, might brush up against a wall, but the arm will physically move your VR body out of the way, so that your view in game sways back like you were stepping away from the wall, even though your IRL body didn't do any of that motion. The end result is that the game is essentially constantly swaying you around, pushing you against walls, through motions you did NOT do. This is
the cardinal sin of VR, you NEVER wrestle movement of the camera away from the user. It makes people VERY sick. This was one of the very first most fundamental lessons learned about VR design.
This is like a VR game straight out of 2013.
