I understand the b2LineJoint to be a prismatic joint, but with rotational freedom--that is, it lets a body slide along a line fixed with respect to another body, and rotate freely. I need this in my game! I could use a revolute joint and a prismatic joint together with an extra body in between. This would be slower, and I need the fastest method. But I use Java, and it appears that the line joint has not been ported. Do you folks plan to port it? If not... could you port it anyway?
...Well, in the long run, I guess the fastest method is to use Box2D instead of JBox2D, probably. Maybe I'll have to port my own thing to C++ anyhow, once I'm done designing and prototyping it in Java. So I won't shrivel and die without a Java-based line joint. But it would be nice!