use mainthread on __APPLE__

remove duplicate SimpleCamera.cpp from cmakelists.txt

examples/TwoJoint/TwoJointMain.cpp

@@ -29,7 +29,12 @@ std::map<std::string, int> jointNameToId;
 
 int main(int argc, char* argv[])
 {
+#ifdef __APPLE__
+	kPhysClient = b3CreateInProcessPhysicsServerAndConnectMainThread(argc, argv);
+#else
 	kPhysClient = b3CreateInProcessPhysicsServerAndConnect(argc, argv);
+#endif
+
 	if (!kPhysClient)
 		return -1;
 	// visualizer
@@ -131,4 +136,4 @@ int main(int argc, char* argv[])
 	}
 	b3DisconnectSharedMemory(kPhysClient);
 	return 0;
-}
+}