Phys2d collision mask

Game Mechanics
#1

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:


       /**
	 * @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