Merge pull request #1091 from YunfeiBai/master

Add APIs to reset object mass, lateral friction coefficient, and to get user constraint id.

examples/SharedMemory/SharedMemoryPublic.h

@@ -55,6 +55,7 @@ enum EnumSharedMemoryClientCommand
     CMD_CONFIGURE_OPENGL_VISUALIZER,
 	CMD_REQUEST_KEYBOARD_EVENTS_DATA,
 	CMD_REQUEST_OPENGL_VISUALIZER_CAMERA,
+	CMD_RESET_DYNAMIC_INFO,
     //don't go beyond this command!
     CMD_MAX_CLIENT_COMMANDS,
     
@@ -215,6 +216,11 @@ struct b3BodyInfo
 	const char* m_bodyName; // for btRigidBody, it does not have a base, but can still have a body name from urdf
 };
 
+struct b3DynamicInfo
+{
+	double m_mass;
+	double m_localInertialPosition[3];
+};
 
 // copied from btMultiBodyLink.h
 enum SensorType {