expose getNumBodies, getBodyUniqueId, getBodyInfo (char* baseName) to shared memory API and pybullet., making it easier to serialize the state of the world.

examples/SharedMemory/PhysicsClientC_API.h

@@ -53,6 +53,15 @@ int b3GetStatusActualState(b3SharedMemoryStatusHandle statusHandle,
                            const double* actualStateQdot[],
                            const double* jointReactionForces[]);
 
+///return the total number of bodies in the simulation
+int	b3GetNumBodies(b3PhysicsClientHandle physClient);
+
+/// return the body unique id, given the index in range [0 , b3GetNumBodies() )
+int b3GetBodyUniqueId(b3PhysicsClientHandle physClient, int serialIndex);
+
+///given a body unique id, return the body information. See b3BodyInfo in SharedMemoryPublic.h
+int b3GetBodyInfo(b3PhysicsClientHandle physClient, int bodyUniqueId, struct b3BodyInfo* info);
+
 ///give a unique body index (after loading the body) return the number of joints.
 int	b3GetNumJoints(b3PhysicsClientHandle physClient, int bodyIndex);