Physics door test

Game.kt

    lateinit var bulletAppState: BulletAppState

    lateinit var playerControl: PlayerControl

// For grabbing
    private var joint: Constraint? = null
    private var handle: RigidBodyControl? = null
    private var grabDistance = 0f
    private var highlighted: Geometry? = null
    private var grabbing: Geometry? = null

    private fun startGame() {
        bulletAppState = BulletAppState()
        stateManager.attach(bulletAppState)
        bulletAppState.getPhysicsSpace().accuracy = 1f/120f

        playerControl = PlayerControl(camera, bulletAppState)
    }

    override fun onAction(binding: String, isPressed: Boolean, tpf: Float) {
        when (binding) {
            "Grab" -> grab(isPressed)
            ...
        }
    }

    private fun grab(pressed: Boolean) {
        if (pressed) {
            startGrab()
        } else {
            releaseGrab()
        }
    }

    private fun releaseGrab() {
        if (joint != null) {
            joint?.bodyA?.removeJoint(joint)
            joint?.bodyB?.removeJoint(joint)
            bulletAppState.physicsSpace.remove(joint)
            bulletAppState.physicsSpace.remove(handle)
            joint = null
            grabbing = null
        }
    }

    private fun startGrab() {
        val pair = findHovering()
        if (pair != null) {
            val (result, gob) = pair
            if (gob.mesh?.flags?.mass ?: 0f > 0f) {
                grabDistance = result.distance
                val contactPoint = gob.getGeom().worldToLocal(result.contactPoint, null)
                grabbing = result.geometry

                if (handle == null) {
                    handle = RigidBodyControl(EmptyShape(true), 4.0f).also {
                        it.isKinematic = true
                        it.rollingFriction = 1000.0f
                        it.contactDamping = 0.0f
                    }
                }
                bulletAppState.physicsSpace.add(handle)
                if (joint == null) {
                    joint = New6Dof(handle, gob.control, Vector3f.ZERO, contactPoint, Matrix3f.IDENTITY, Matrix3f.IDENTITY, RotationOrder.XYZ).also {
                        it.setStiffness(PhysicsSpace.AXIS_X + 3, 0.3f, true)
                        it.setStiffness(PhysicsSpace.AXIS_Y + 3, 0.3f, true)
                        it.setStiffness(PhysicsSpace.AXIS_Z + 3, 0.3f, true)
                        bulletAppState.physicsSpace.add(it)
                    }
                }
                updateGrab()
            }
        }
    }

    override fun simpleUpdate(tpf: Float) {
        ...
      
        if (joint != null && handle != null) {
            updateGrab()
        }

        ...
    }

    private fun updateGrab() {
        val pos = cam.location.add(cam.getDirection().mult(grabDistance))
        handle?.physicsLocation = pos
    }
}