Phys2d collision mask

[newera31]

Hello,

I am running into some troubles with the Phys2d bitmask on Body's.  I would expect that having a collision group of 1 set on two Body's would allow them to collide with each other.  However I could not get this to work, so I dug around in the code and noticed this in CollisionSpace.java:

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/**     * @see net.phys2d.raw.CollisionContext#resolve(net.phys2d.raw.BodyList, float)     */    public void resolve(BodyList bodyList, float dt) {       for (int i = 0; i < bodyList.size(); ++i)       {          Body bi = bodyList.get(i);          if (bi.disabled()) {             continue;          }                    for (int j = i+1; j < bodyList.size(); ++j)          {             Body bj = bodyList.get(j);             if (bj.disabled()) {                continue;             }                                 // should this be if ((bi.getBitmask() & bj.getBitmask()) == 0)?            if ((bi.getBitmask() & bj.getBitmask()) != 0) {                continue;             } ...

Has any one else encountered this problem?  In order for collision groups to work they have to be non-matching bits? - that doesn't make sense...

Thanks,

Tony