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EventBase.h

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00001 //-*-c++-*-
00002 #ifndef INCLUDED_EventBase_h
00003 #define INCLUDED_EventBase_h
00004 
00005 #include "Shared/get_time.h"
00006 #include "Shared/XMLLoadSave.h"
00007 #include <string>
00008 
00009 //! Forms the basis of communication between modules/behaviors in the framework
00010 /*! 
00011  *  Events are defined by a 3-tuple:
00012  *  - The @b generator indicates the class of the creator of the event, and in practice also generally implies the type (i.e. subclass) of the event itself.
00013  *  - The @b source indicates the instance of the creator of the event, which differentiates when more than one generator is available.
00014  *  - The @b type indicates the role of the event among other events from the source.
00015  *
00016  *  Each of these is represented by an ID, the #EventGeneratorID_t (EGID) and #EventTypeID_t (ETID) are
00017  *  defined here in EventBase.  Source IDs (SID) are defined separately by each generator, so the
00018  *  documentation in each entry of EventGeneratorID_t describes how to interpret the source field.
00019  *
00020  *  So for example, the button event which results from initially pressing the head button on an ERS-7
00021  *  robot would be:
00022  *  <center>(EventBase::buttonEGID, ERS7Info::HeadButOffset, EventBase::activateETID)</center>
00023  *
00024  *  While the button is held down, additional #statusETID events are used to report varying pressure values (if the button
00025  *  is pressure sensitive), and an event with #deactivateETID is sent when the button is released.
00026  *  Alternatively, an SID value from a vision detector (say #visObjEGID) refers to seeing a particular object, a completely
00027  *  different domain, values of which may overlap with other generators' source IDs.
00028  *  Thus, interpreting the source field requires knowing the generator as well.
00029  *
00030  *  When the generator doesn't have groups of activity with a 'begin' or 'end', it will use #statusETID
00031  *  for all of its events.  (in other words, not all generators necessarily have to use activate or deactivate)
00032  *  For example, sensor updates are continuously occuring, so you will only ever see
00033  *  <center>(EventBase::sensorEGID,SensorSourceID::UpdatedSID,EventBase::statusETID)</center>
00034  *  
00035  *  The #duration field is also generator specific - some may refer to
00036  *  the time since the last activation event (e.g. button events)
00037  *  where as others refer to time since last status (e.g. sensors
00038  *  updates)
00039  *
00040  *  If you want to make a new generator, all you have to do is add a new entry
00041  *  to the ID list (#EventGeneratorID_t) and then put its name in the 
00042  *  #EventGeneratorNames[] array.  Alternatively, there is an 'unlicensed spectrum' available under
00043  *  #unknownEGID.  You can send out events from that generator just
00044  *  like any other, but it should only be used for quick tests and hacking
00045  *  around...
00046  *
00047  *  The generator ID number is only that -- an ID number.  
00048  *  Events can be posted to the EventRouter anywhere, anytime,
00049  *  and do not require anything of the sender.  However, there is an EventGeneratorBase which
00050  *  can simplify some aspects of behaviors whose sole purpose is processing information
00051  *  and generating events.
00052  *
00053  *  If more information needs to be sent along with the event, the
00054  *  cleanest solution is to create a subclass of EventBase to hold the
00055  *  additional information.  For example, you can see the existing
00056  *  subclasses in the inheritance diagram above.  If you want to use a
00057  *  quick hack however, you could just pass a pointer to data as the SID if you
00058  *  don't need that field for something else, or use a DataEvent.
00059  *
00060  *  @note All subclasses must override getClassTypeID() and provide
00061  *  a unique value to allow fast polymorphic serialization for inter-process
00062  *  communication.  Implementing the load/save functions
00063  *  ({load,save}BinaryBuffer and {load,save}XML) for your addtional data fields
00064  *  would also be necessary in order to allow your event to be sent between
00065  *  processes, or eventually, between robots.
00066  * 
00067  *  @see EventRouter for discussion on sending and receiving of events
00068  *  @see Tutorials:
00069  *    - <a href="../FirstBehavior2.html">Steps 3, 4, & 5 of Tekkotsu's First Behavior Tutorial</a>
00070  *    - <a href="http://www.cs.cmu.edu/~dst/Tekkotsu/Tutorial/events.shtml">David Touretzky's Events Chapter</a>
00071  *    - <a href="http://www.cs.cmu.edu/afs/cs/academic/class/15494-s06/www/lectures/behaviors.pdf">CMU's Cognitive Robotics course slides</a>
00072  *    - <a href="../media/TekkotsuQuickReference_ERS7.pdf">ERS-7 Quick Reference Sheet</a>
00073  */
00074 class EventBase : public XMLLoadSave {
00075  public:
00076   //! Lists all possible event generator ids
00077   /*! An event generator is a abstract source of events, used for listening to and parsing certain classes of events
00078    *
00079    *  IF YOU ADD AN EVENT GENERATOR, DON'T FORGET TO NAME IT (EventBase::EventGeneratorNames, actual names are in EventBase.cc)*/
00080   enum EventGeneratorID_t {
00081     unknownEGID=0,    //!< default EGID, used if you forget to set it, probably not a good idea to use this for anything except errors or testing quick hacks
00082     aiEGID,           //!< not being used, yet (might use this when AI makes decisions?)
00083     audioEGID,        //!< Sends an event when a sound starts/ends playback, status events as chained sounds end; SID is SoundManager::Play_ID; duration is playtime
00084     buttonEGID,       //!< Sends activate event for button down, deactivate for button up.  Status events only for when pressure sensitive buttons' reading changes. (on sensorEGID updates); SIDs are from ButtonOffset_t in the namespace of the target model (e.g. ERS210Info::ButtonOffset_t); duration is button down time
00085     erouterEGID,      //!< Sends activate event on first listener, deactivate on last listener, and status on other listener changes.; SID is the generator ID affected
00086     estopEGID,        //!< Sends an event when the estop is turned on or off; SID is the MotionManager::MC_ID of the EmergencyStopMC; duration is length of estop activation
00087     locomotionEGID,   //!< Sends events regarding transportation in the world; you can/should assume these will all be LocomotionEvent classes; SID is MotionManager::MC_ID of posting MotionCommand; duration is the time since last velocity change of that MC. (You could generate these for things other than walking...)
00088     lookoutEGID,      //!< Sends an event when Lookout request is complete; SID is the id for lookout request
00089     mapbuilderEGID,  //!< Sends a status event when map is completed
00090     micOSndEGID,      //!< Sends a DataEvent<OSoundVectorData> for every audio buffer received from the system; SID and duration are always 0 (This is generated by the MainObj instantiation of MMCombo)
00091     micRawEGID,       //!< reserved for future use
00092     micFFTEGID,       //!< reserved for future use
00093     micPitchEGID,       //!< Sends a PitchEvent when a particular frequency is detected; SID is a pointer to the PitchDetector, magnitude is product of amplitude and confidence
00094     motmanEGID,       //!< Sends events when a MotionCommand is added or removed, SID is is the MotionManager::MC_ID, duration is always 0; individual MotionCommands may throw status events to signal intermediary status
00095     pilotEGID,        //!< Sends events when position of agent is updated or pilot request is completed
00096     powerEGID,        //!< Sends events for low power warnings, temperature, etc. see PowerSourceID::PowerSourceID_t
00097     sensorEGID,       //!< Sends a status event when new sensor readings are available. see SensorSourceID::SensorSourceID_t
00098     stateMachineEGID, //!< Sends an event upon entering and leaving a StateNode; SID is pointer to the StateNode; duration is always 0; some state will throw a status event when they have completed their task and are now idling
00099     stateSignalEGID,  //!< Sends a DataEvent that can be monitored by a SignalTrans for triggering a state transition
00100     stateTransitionEGID, //!< Sends an event each time a transition is triggered; SID is a pointer to the transition; type is always status, duration is always 0; guaranteed to occur immediately *before* the transition actually occurs
00101     textmsgEGID,      //!< Sends status events when a text msg is received on console; generated by the Controller, SID is 0 if broadcast from ControllerGUI, 1 if "private" from BehaviorSwitchControl; duration is always 0 (see Controller for more information)
00102     timerEGID,        //!< Sends timer events; you set timers explicitly, you don't have to listen as well. (See EventRouter::addTimer()) There's no cross-talk, only the listener which requested the timer will receive it; SID is whatever you requested it to be; duration is the time (since boot, in ms) that the timer was supposed to go off; these are always status
00103     visOFbkEGID,      //!< Sends a DataEvent < OFbkImageVectorData > for every camera image received from the system; SID and duration are always 0 (This is generated by the MainObj instantiation of MMCombo)
00104     visRawCameraEGID, //!< Sends a FilterBankEvent when new raw camera images are available; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00105     visInterleaveEGID,//!< Sends a FilterBankEvent when new interleaved images are available; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00106     visJPEGEGID,      //!< Sends a FilterBankEvent when JPEG compressed images are available; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00107     visPNGEGID,      //!< Sends a FilterBankEvent when PNG compressed images are available; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00108     visSegmentEGID,   //!< Sends a SegmentedColorFilterBankEvent when color segmentated images are available; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00109     visRLEEGID,       //!< Sends a SegmentedColorFilterBankEvent when RLE encoded color segmentated images are available; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00110     visRegionEGID,    //!< Sends a SegmentedColorFilterBankEvent when color regions are available; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00111     visObjEGID,       //!< Sends VisionObjectEvents for objects detected in camera images; SID is whatever value you gave during setup (typically in StartupBehavior_SetupVision.cc), duration is always 0
00112     wmVarEGID,        //!< Sends an event when a watched memory is changed; source id is pointer to WMEntry
00113     worldModelEGID,   //!< not being used, yet (for when objects are detected/lost?)
00114     numEGIDs          //!< the number of generators available
00115   };
00116 
00117   //! Holds string versions of each of the generator's names, handy for debugging so you can output the events as readable strings (you'll find this in EventBase.cc since it can't go in the header or we get multiply-defined errors during linking)
00118   static const char* const EventGeneratorNames[numEGIDs];
00119   
00120   //! an event type id is used to denote whether it's the first in a sequence (button down), in a sequence (button still down), or last (button up)
00121   enum EventTypeID_t {
00122     activateETID,   //!< Start of an event sequence, e.g. button down
00123     statusETID,     //!< Indicates a value has changed, e.g. new sensor readings
00124     deactivateETID, //!< Last of a series of events, e.g. button up
00125     numETIDs        //!< the number of different event types
00126   };
00127   
00128   //! holds string versions of EventTypeID_t
00129   static const char* const EventTypeNames[numETIDs];
00130   
00131   //! holds abbreviated string versions of EventTypeID_t
00132   static const char* const EventTypeAbbr[numETIDs];
00133 
00134   /*! @name Constructors/Destructors */
00135   //! constructor
00136   /*! @see EventRouter::postEvent() */
00137   EventBase(); 
00138   EventBase(EventGeneratorID_t gid, unsigned int sid, EventTypeID_t tid, unsigned int dur=0);
00139   EventBase(EventGeneratorID_t gid, unsigned int sid, EventTypeID_t tid, unsigned int dur, const std::string& n);
00140   EventBase(EventGeneratorID_t gid, unsigned int sid, EventTypeID_t tid, unsigned int dur, const std::string& n, float mag);
00141   virtual ~EventBase() {} //!< destructor
00142 
00143   //! allows a copy to be made of an event, supporting polymorphism
00144   /*! Must be overridden by all subclasses to allow this to happen
00145    * 
00146    *  I would like to switch this over to the cloneable interface once
00147    *  the compiler gets updated out of the 3.3 branch... see
00148    *  Cloneable::clone() for a discussion of the issue and
00149    *  implementation notes. */
00150   virtual EventBase* clone() const { return new EventBase(*this); }
00151   //@}
00152 
00153   /*! @name Methods */
00154   virtual const std::string& getName() const { return stim_id; } //!< gets the name of the event - useful for debugging output, see also getDescription()
00155   virtual EventBase& setName(const std::string& n); //!< sets name to a given string, prevents overwriting by generated names
00156 
00157   virtual float getMagnitude() const { return magnitude; } //!< gets "strength" of event - by default 1 for activate and status events, 0 for deactivate events
00158   virtual EventBase& setMagnitude(float m) { magnitude=m; return *this; }//!< sets "strength" of event - you may want to override the default values (see getMagnitude())
00159 
00160   virtual unsigned int getTimeStamp() const { return timestamp; } //!< time event was created
00161   virtual void setTimeStamp(unsigned int t) { timestamp=t; } //!< resets time event was created
00162 
00163   virtual EventGeneratorID_t getGeneratorID() const { return genID; } /*!< @brief gets the generator ID for this event @see EventGeneratorID_t */
00164   virtual EventBase& setGeneratorID(EventGeneratorID_t gid) { genID=gid; genName(); return *this; } /*!< @brief sets the generator ID for this event @see EventGeneratorID_t */
00165   
00166   virtual unsigned int getSourceID() const { return sourceID; } /*!< @brief gets the source ID for this event @see sourceID */
00167   virtual EventBase& setSourceID(unsigned int sid) { sourceID=sid; genName(); return *this; } /*!< @brief sets the source ID for this event @see sourceID */
00168   
00169   virtual EventTypeID_t getTypeID() const { return typeID; } /*!< @brief gets the type ID @see EventTypeID_t */
00170   virtual EventBase& setTypeID(EventTypeID_t tid) { typeID=tid; unsigned int n=strlen(EventTypeAbbr[typeID]); stim_id.replace(stim_id.size()-n-1,n,EventTypeAbbr[typeID]); return *this; } /*!< @brief sets the type ID @see EventTypeID_t */
00171 
00172   virtual unsigned int getDuration() const { return duration; } /*!< @brief gets the time since the beginning of this sequence (the timestamp of the activate event) @see duration */
00173   virtual EventBase& setDuration(unsigned int d) { duration = d; return *this; }/*!< @brief sets the time since the beginning of this sequence (the timestamp of the activate event) @see duration */
00174 
00175   virtual const std::string& resetName() { nameisgen=true; genName(); return stim_id; } //!< resets name to generated form, overwriting any previous name
00176   virtual bool isCustomName() const { return !nameisgen; } //!< returns true if not using the generated name
00177 
00178   //! generates a description of the event with variable verbosity 
00179   /*! @param showTypeSpecific should be read by subclasses to add additional information
00180    *  @param verbosity can be one of the following values:
00181    *    - 0 - Basic: <i>event_name</i> \\t <i>generator_id</i> \\t <i>source_id</i> \\t <i>type_id</i>
00182    *    - 1 - Numerics: <i>event_name</i> \\t <i>generator_id</i> \\t <i>source_id</i> \\t <i>type_id</i>
00183    *    - 2 - Timing: <i>event_name</i> \\t <i>generator_id</i> \\t <i>source_id</i> \\t <i>type_id</i> \\t <i>duration</i> \\t <i>timestamp</i>
00184    *    - 3 and above - Full: <i>event_name</i> \\t <i>generator_id</i> \\t <i>source_id</i> \\t <i>type_id</i> \\t <i>duration</i> \\t <i>timestamp</i> \\t <i>magnitude</i>
00185    *  if showTypeSpecific, additional fields will be added after the common fields listed above. */
00186   virtual std::string getDescription(bool showTypeSpecific=true, unsigned int verbosity=0) const; 
00187 
00188   inline bool operator<(const EventBase& e) const { return timestamp<e.timestamp; }
00189 
00190   //! is true if the genID, typeID, and sourceID's all match
00191   virtual bool operator==(const EventBase& eb) const {
00192     return (sourceID==eb.sourceID && genID==eb.genID && typeID==eb.typeID);
00193   }
00194   //!tests to see if events have the same generator and source IDs
00195   bool sameGenSource(const EventBase& eb) const { return genID==eb.genID && sourceID==eb.sourceID; }
00196   
00197   bool longerThan(const EventBase& eb) const { return duration>eb.duration && *this==eb; } //!< compares event duration and ensures same event generator, source, and type - useful for event masks
00198   bool shorterThan(const EventBase& eb) const { return duration<eb.duration && *this==eb; }//!< compares event duration and ensures same event generator, source, and type - useful for event masks
00199   bool equalOrLongerThan(const EventBase& eb) const { return duration>=eb.duration && *this==eb; }//!< compares event duration and ensures same event generator, source, and type - useful for event masks
00200   bool equalOrShorterThan(const EventBase& eb) const { return duration<=eb.duration && *this==eb; }//!< compares event duration and ensures same event generator, source, and type - useful for event masks
00201   
00202   static bool isValidGeneratorID(unsigned int egid) { return egid<numEGIDs; }
00203   //@}
00204 
00205   //! Useful for serializing events to send between processes
00206   /*! @name LoadSave interface */
00207 
00208   //! All subclasses should override this and return a unique ID for their class.
00209   /*! All IDs corresponding to all-capital letters are reserved for future
00210    *  framework expansion.  (Thus, user subclasses should contain at least one
00211    *  lower-case letter.)  This code can be used when serializing to allow quick
00212    *  identification of the class type by the receiver. */
00213   virtual unsigned int getClassTypeID() const { return makeClassTypeID("BASE"); }
00214 
00215   virtual unsigned int getBinSize() const; //!< should return the minimum size needed if using binary format (i.e. not XML)
00216   virtual unsigned int loadBinaryBuffer(const char buf[], unsigned int len); //!< load from binary format
00217   virtual unsigned int saveBinaryBuffer(char buf[], unsigned int len) const; //!< save to binary format
00218   virtual void loadXML(xmlNode* node); //!< load from XML format
00219   virtual void saveXML(xmlNode * node) const; //!< save to XML format
00220   
00221   //! no longer need to override this -- will automatically call either loadXML() or loadBinaryBuffer() based on #saveFormat
00222   /*! tries to be smart so if the load based on the current #saveFormat fails, retries with the alternative format */
00223   virtual unsigned int loadBuffer(const char buf[], unsigned int len)  {
00224     unsigned int test = saveFormat!=BINARY ? XMLLoadSave::loadBuffer(buf,len) : loadBinaryBuffer(buf,len);
00225     if(test!=0) //if the default didn't work, try the other format too...
00226       return test;
00227     return saveFormat!=BINARY ? loadBinaryBuffer(buf,len) : XMLLoadSave::loadBuffer(buf,len);
00228   }
00229   //! no longer need to override this -- will automatically call either saveXML() or saveBinaryBuffer() based on #saveFormat
00230   virtual unsigned int saveBuffer(char buf[], unsigned int len) const { return saveFormat!=BINARY ? XMLLoadSave::saveBuffer(buf,len) : saveBinaryBuffer(buf,len); }
00231 
00232   //! automatically calls either XMLLoadSave::loadFile or LoadSave::loadFile based on #saveFormat
00233   /*! tries to be smart so if the load based on the current #saveFormat fails, retries with the alternative format */
00234   virtual unsigned int loadFile(const char* filename) {
00235     unsigned int test = saveFormat!=BINARY ? XMLLoadSave::loadFile(filename) : LoadSave::loadFile(filename);
00236     if(test!=0) //if the default didn't work, try the other format too...
00237       return test;
00238     return saveFormat!=BINARY ? LoadSave::loadFile(filename) : XMLLoadSave::loadFile(filename);
00239   }
00240   //! automatically calls either XMLLoadSave::saveFile or LoadSave::saveFile based on #saveFormat
00241   virtual unsigned int saveFile(const char* filename) const { return saveFormat!=BINARY ? XMLLoadSave::saveFile(filename) : LoadSave::saveFile(filename); }
00242   
00243   //! automatically calls either XMLLoadSave::loadFileStream or LoadSave::loadFileStream based on #saveFormat
00244   virtual unsigned int loadFileStream(FILE* f) { return saveFormat!=BINARY ? XMLLoadSave::loadFileStream(f) : LoadSave::loadFileStream(f); }
00245   //! automatically calls either XMLLoadSave::loadFileStream or LoadSave::loadFileStream based on #saveFormat
00246   virtual unsigned int saveFileStream(FILE* f) const { return saveFormat!=BINARY ? XMLLoadSave::saveFileStream(f) : LoadSave::saveFileStream(f); }
00247   
00248   //! values to pass to setSaveFormat()
00249   enum SaveFormat {
00250     BINARY, //!< saves will be in packed binary, loads will try binary first
00251     XML //!< saves will be in xml, loads will try xml first
00252   };
00253   virtual void setSaveFormat(SaveFormat sf) const { saveFormat=sf; } //!< set #saveFormat
00254   virtual SaveFormat getSaveFormat() const { return saveFormat; } //!< return #saveFormat
00255   //@}
00256   
00257  protected:
00258   //! converts the first 4 characters of @a str to an unsigned int, should ensure consistent byte ordering across platforms
00259   /*! The numeric value may differ between platforms, but it will be consistent
00260    *  with the IDs on that platform, which is the real key since we aren't doing
00261    *  math, just equality */
00262   static unsigned int makeClassTypeID(const char* str) { return *reinterpret_cast<const unsigned int*>(str); }
00263 
00264   std::string stim_id; //!< the name of the event, use the same name consistently or else will be seen as different stimuli
00265   float magnitude; //!< the current "strength" of the event/stimuli... MAKE SURE this gets set to ZERO IF event is DEACTIVATE
00266   unsigned int timestamp; //!< the time the event was created - set automatically by constructor
00267 
00268   mutable SaveFormat saveFormat; //!< controls the format used during the next call to saveBuffer() (packed binary or XML)
00269 
00270   bool nameisgen; //!< tracks whether the current name (stim_id) was generated by genName() (true) or setName() (false)
00271   virtual void genName(); //!< calls setName() with a string version of sourceID, decimal notation
00272 
00273   EventGeneratorID_t genID; //!< generator ID, see EventGeneratorID_t
00274   EventTypeID_t typeID; //!< type ID, see EventTypeID_t
00275   size_t sourceID;       /*!< @brief the source ID for this event
00276                           * Source IDs are defined by the generator that made it.  This should
00277                           * give authors flexibility to design their modules without having to
00278                           * worry about ID space collision */
00279   unsigned int duration; /*!< @brief the time since this sequence started (like, how long the
00280                           *   button has been pressed); not all generators will set this;
00281                           *   Typically, this would be 0 for activate,
00282                           *   (activate.timestamp-::get_time()) for status and deactivate */
00283 };
00284 
00285 /*! @file
00286  * @brief Describes EventBase, the basic class for sending events around the system
00287  * @author ejt (Creator)
00288  *
00289  * $Author: ejt $
00290  * $Name: tekkotsu-3_0 $
00291  * $Revision: 1.50 $
00292  * $State: Exp $
00293  * $Date: 2006/10/03 23:19:23 $
00294  */
00295 
00296 #endif

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