add getSpatial() methods to GhostControl and RigidBodyControl

[stephengold]

com.jme3.bullet.control.GhostControl and com.jme3.bullet.control.RigidBodyControl provide setters for the controlled spatial, but no getter.

Related forum topic:
https://hub.jmonkeyengine.org/t/how-to-make-projectiles/41301

[quazi-irfan]

I was thinking I just need to add a very simple getter that returns the protected Spatial in both GhostControl and RigidBodyControl classes.

But to see if that's the only thing I needed to do - I checked the other classes in the control folder, and I've found that none of the classes in control folder has getSpatial Method.

getSpatial is not only missing in GhostControl and RigidBodyControl class, but it was missing in all classed in this folder: https://github.com/quazi-irfan/jmonkeyengine/tree/master/jme3-bullet/src/common/java/com/jme3/bullet/control

Instead of getSpatial method, they have other getter methods. Such as, getSpatialTranslation and getSpatialRotation.

Thoughts?

[stephengold]

Thanks for looking into this.

VehicleControl is a subclass of RigidBodyControl, so adding getSpatial() to RBC will address the needs of VehicleControl.
BetterCharacterControl and KineticRagdollControl are subclasses of AbstractPhysicsControl, which doesn't have getSpatial() yet.

So yes. Please implement getSpatial() for AbstractPhysicsControl and CharacterControl also.

[quazi-irfan]

VehicleControl is not a subclass of RigidBodyControl, but it implements PhysicsControl.

I am supposed to add getSpatial() to the following classes,

• GhostControl extends PhysicsGhostObject implements PhysicsControl, JmeCloneable
• RigidBodyControl extends PhysicsRigidBody implements PhysicsControl, JmeCloneable
• AbstractPhysicsControl implements PhysicsControl, JmeCloneable
• CharacterControl extends PhysicsCharacter implements PhysicsControl, JmeCloneable

Note that all 4 classes extends PhysicsControl interface. So would it make more sense to add getSpatial() in the super interface?

[pspeed42]

I kind of agree that PhysicsControl should have a getSpatial() method... which would force all of those others to implement it somewhere.

As I recall, the point of this is because PhysicsControls will show up in collision events? If so then, yes, PhysicsControl should definitely have getSpatial().

[stephengold]

Sorry I was confused about VehicleControl.

The issue I see with adding getSpatial() to PhysicsControl would be that users might create their own classes that implement PhysicsControl, and changing PhysicsControl would break their code.

If we do add it to PhysicsControl then I request that the commit be in a separate PR.

[quazi-irfan]

Should I go ahead and add getSpatial() to the 4 classes?

[stephengold]

Yes.

[quazi-irfan]

Pull Request #1041 submitted with requested changed.

Are we going to remove getSpatial method from these 4 classes and add it to PhysicsControl interface for 3.3 release?

[pspeed42]

PhysicsControl is an interface. If you add the method there then you will still need it on these classes.

[quazi-irfan]

I thought, you would not need it, if getSpatial is marked as default method in the interface.

[pspeed42]

Interfaces can't have implementations. Some class will have to implement the method... anything with "implements PhysicsControl" would have to implement the method.

Are you thinking of a different language maybe?