Feat: Synthetic channel to keep parked aircraft, closes #255

CMakeLists.txt

@@ -151,6 +151,7 @@ set(Header_Files
     Include/LTOpenGlider.h
     Include/LTOpenSky.h
     Include/LTRealTraffic.h
+    Include/LTSynthetic.h
     Include/LTWeather.h
     Include/Network.h
     Include/SettingsUI.h
@@ -196,6 +197,7 @@ set(Source_Files
     Src/LTOpenGlider.cpp
     Src/LTOpenSky.cpp
     Src/LTRealTraffic.cpp
+    Src/LTSynthetic.cpp
     Src/LTVersion.cpp
     Src/LTWeather.cpp
     Src/Network.cpp

Include/Constants.h

@@ -73,6 +73,7 @@ constexpr double AC_MAINT_INTVL     = 2.0;      // seconds (calling a/c maintena
 constexpr double TIME_REQU_POS      = 0.5;      // seconds before reaching current 'to' position we request calculation of next position
 constexpr double SIMILAR_TS_INTVL = 3;          // seconds: Less than that difference and position-timestamps are considered "similar" -> positions are merged rather than added additionally
 constexpr double SIMILAR_POS_DIST = 7;          // [m] if distance between positions less than this then favor heading from flight data over vector between positions
+constexpr double GND_COLLISION_DIST = 10;       // [m] If another aircraft comes this close to a parked aircraft then the parked aircraft is removed
 constexpr double FD_GND_AGL =       10;         // [m] consider pos 'ON GRND' if this close to YProbe
 constexpr double FD_GND_AGL_EXT =   20;         // [m] consider pos 'ON GRND' if this close to YProbe - extended, e.g. for RealTraffic
 constexpr double PROBE_HEIGHT_LIM[] = {5000,1000,500,-999999};  // if height AGL is more than ... feet

Include/DataRefs.h

@@ -426,6 +426,7 @@ enum dataRefsLT {
     // channels, in ascending order of priority
     DR_CHANNEL_FUTUREDATACHN_ONLINE,    // placeholder, first channel
     DR_CHANNEL_FORE_FLIGHT_SENDER,
+    DR_CHANNEL_SYNTHETIC,
     DR_CHANNEL_FSCHARTER,
     DR_CHANNEL_OPEN_GLIDER_NET,
     DR_CHANNEL_ADSB_HUB,

Include/LTADSBHub.h

@@ -76,7 +76,7 @@ class ADSBHubConnection : public LTFlightDataChannel
 public:
     /// Constructor
     ADSBHubConnection ();
-    /// Invokes APRS thread, or returns URL to fetch current data from live.glidernet.org
+    /// No URL involved
     std::string GetURL (const positionTy&) override { return ""; }
     /// @brief Processes the fetched data
     bool ProcessFetchedData () override { return true; };

Include/LTApt.h

@@ -56,6 +56,15 @@ inline positionTy LTAptFindRwy (const LTAircraft& _ac, std::string& _rwyId, bool
                          bDoLogging ? std::string(_ac) : "");
 }
 
+/// @brief Find close-by startup position
+/// @param pos Searching around this position
+/// @param maxDist Max search distance
+/// @param[out] outDist Receives distances between search pos and startup location, or `NAN` if no startup location found
+/// @return Position of search position, heading is set to startup heading
+positionTy LTAptFindStartupLoc (const positionTy& pos,
+                                double maxDist = NAN,
+                                double* outDist = nullptr);
+
 /// @brief Snaps the passed-in position to the nearest rwy or taxiway if appropriate
 /// @param fd Flight data object to be analyzed
 /// @param[in,out] posIter Iterator into LTFlightData::posDeque, points to position to analyze, might change due to inserted taxi positions

Include/LTChannel.h

@@ -46,6 +46,7 @@ class LTChannel
     enum LTChannelType {
         CHT_UNKNOWN = 0,
         CHT_TRACKING_DATA,
+        CHT_SYNTHETIC_DATA,         ///< data created internally by LiveTraffic, like kept parked aircraft, has lower priority than any real-life data
         CHT_MASTER_DATA,
         CHT_TRAFFIC_SENDER,         // sends out data (not receiving)
     };
@@ -192,8 +193,8 @@ class LTFlightDataChannel : public LTOnlineChannel {
     mutable float timeLastAcCnt = 0.0;      ///< when did we last count the a/c served by this channel?
     mutable int     numAcServed = 0;        ///< how many a/c do we feed when counted last?
 public:
-    LTFlightDataChannel (dataRefsLT ch, const char* chName) :
-        LTOnlineChannel(ch, CHT_TRACKING_DATA, chName) {}
+    LTFlightDataChannel (dataRefsLT ch, const char* chName, LTChannelType eType = CHT_TRACKING_DATA) :
+        LTOnlineChannel(ch, eType, chName) {}
     int GetNumAcServed () const override;   ///< how many a/c do we feed when counted last?
 };
 
@@ -315,6 +316,8 @@ class LTACMasterdataChannel : public LTOnlineChannel
     /// @brief Register a master data channel, that will be called to process requests
     /// @note The order, in which registration happens, serves as a priority
     static void RegisterMasterDataChn (LTACMasterdataChannel* pChn);
+    /// Unregister a mster data channel
+    static void UnregisterMasterDataChn (LTACMasterdataChannel* pChn);
     /// Generically, uniquely add request to fetch data (returns `true` if added, `false` if duplicate)
     static bool RequestMasterData (const LTFlightData::FDKeyTy& keyAc,
                                    const std::string& callSign,

Include/LTRealTraffic.h

@@ -1,12 +1,16 @@
 /// @file       LTRealTraffic.h
 /// @brief      RealTraffic: Receives and processes live tracking data
 /// @see        https://rtweb.flyrealtraffic.com/
-/// @details    Defines RealTrafficConnection:\n
-///             - Sends current position to RealTraffic app\n
-///             - Receives tracking data via UDP\n
-///             - Interprets the response and passes the tracking data on to LTFlightData.\n
+/// @details    Defines RealTrafficConnection in two different variants:\n
+///             - Direct Connection:
+///               - Expects RealTraffic license information
+///               - Sends authentication, weather, and tracking data requests to RealTraffic servcers
+///             - via RealTraffic app
+///               - Sends current position to RealTraffic app\n
+///               - Receives tracking data via UDP\n
+///               - Interprets the response and passes the tracking data on to LTFlightData.\n
 /// @author     Birger Hoppe
-/// @copyright  (c) 2019-2020 Birger Hoppe
+/// @copyright  (c) 2019-2024 Birger Hoppe
 /// @copyright  Permission is hereby granted, free of charge, to any person obtaining a
 ///             copy of this software and associated documentation files (the "Software"),
 ///             to deal in the Software without restriction, including without limitation

Include/LTSynthetic.h

@@ -0,0 +1,63 @@
+/// @file       LTSynthetic.h
+/// @brief      Synthetic tracking data, e.g. for parked aircraft
+/// @details    Defines SyntheticConnection:
+///             - Scans mapFd (all available tracking data in LiveTraffic)
+///               for parked aircraft and keeps a position copy
+///             - For any parked aircraft no longer actively served by any other channel,
+///               send the same position data regularly
+/// @author     Birger Hoppe
+/// @copyright  (c) 2024 Birger Hoppe
+/// @copyright  Permission is hereby granted, free of charge, to any person obtaining a
+///             copy of this software and associated documentation files (the "Software"),
+///             to deal in the Software without restriction, including without limitation
+///             the rights to use, copy, modify, merge, publish, distribute, sublicense,
+///             and/or sell copies of the Software, and to permit persons to whom the
+///             Software is furnished to do so, subject to the following conditions:\n
+///             The above copyright notice and this permission notice shall be included in
+///             all copies or substantial portions of the Software.\n
+///             THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+///             IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+///             FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+///             AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+///             LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+///             OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+///             THE SOFTWARE.
+
+#ifndef LTSynthetic_h
+#define LTSynthetic_h
+
+#include "LTChannel.h"
+
+//
+// MARK: SyntheticConnection
+//
+
+/// Synthetic tracking data creation
+class SyntheticConnection : public LTFlightDataChannel
+{
+protected:
+    /// What information are we storing for parked planes
+    struct SynDataTy {
+        LTFlightData::FDStaticData stat;        // plane's static data
+        positionTy pos;                         // plane's position
+    };
+    /// Stores position per tracked plane
+    typedef std::map<LTFlightData::FDKeyTy, SynDataTy> mapSynDataTy;
+    /// @brief Position information per tracked plane
+    /// @note Defined `static` to preserve information across restarts
+    static mapSynDataTy mapSynData;
+public:
+    /// Constructor
+    SyntheticConnection ();
+    /// No URL involved
+    std::string GetURL (const positionTy&) override { return ""; }
+    /// Scan for relevant flight data
+    bool FetchAllData(const positionTy&) override;
+    /// Processes the available stored data
+    bool ProcessFetchedData () override;
+
+protected:
+    void Main () override;          ///< virtual thread main function
+};
+
+#endif /* LTSynthetic_h */

Include/LiveTraffic.h

@@ -141,6 +141,7 @@ extern DataRefs dataRefs;
 #include "LTADSBHub.h"
 #include "LTOpenGlider.h"
 #include "LTFSCharter.h"
+#include "LTSynthetic.h"
 
 //MARK: Global Control functions
 bool LTMainInit ();

Lib/ImGui/imstb_truetype.h

@@ -3168,7 +3168,7 @@ static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e,
          stbtt__active_edge * z = *step;
          if (z->ey <= scan_y_top) {
             *step = z->next; // delete from list
-            STBTT_assert(z->direction);
+            STBTT_assert(bool(z->direction));       // TwinFan: Silenced compiler warning on implicit type cast
             z->direction = 0;
             stbtt__hheap_free(&hh, z);
          } else {

LiveTraffic.xcodeproj/project.pbxproj

@@ -44,6 +44,7 @@
 		25D293F725C625710007C72E /* Cocoa.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 25D293F625C625710007C72E /* Cocoa.framework */; };
 		25D293FD25C625C10007C72E /* libcurl.tbd in Frameworks */ = {isa = PBXBuildFile; fileRef = 25D293FC25C625C10007C72E /* libcurl.tbd */; };
 		25E9C2AF207D5B8100D3C642 /* LTFlightData.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 25E9C2AE207D5B8100D3C642 /* LTFlightData.cpp */; };
+		25EF90042B497C6100D7C805 /* LTSynthetic.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 25EF90032B497C6100D7C805 /* LTSynthetic.cpp */; };
 		25F3471C24D2C7DE004574E7 /* parson.c in Sources */ = {isa = PBXBuildFile; fileRef = 25F3471B24D2C7DE004574E7 /* parson.c */; settings = {COMPILER_FLAGS = "-Wno-sign-conversion"; }; };
 		25F3471F24D2CB20004574E7 /* ACTable.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 25F3471E24D2CB20004574E7 /* ACTable.cpp */; };
 		25FEB7B9224D7B10002A051F /* LTForeFlight.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 25FEB7B8224D7B10002A051F /* LTForeFlight.cpp */; };
@@ -177,6 +178,8 @@
 		25D811002402D60A00A8723B /* README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };
 		25DC1E2A21B72922008D0F8B /* Data */ = {isa = PBXFileReference; lastKnownFileType = folder; path = Data; sourceTree = "<group>"; };
 		25E9C2AE207D5B8100D3C642 /* LTFlightData.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = LTFlightData.cpp; sourceTree = "<group>"; };
+		25EF90032B497C6100D7C805 /* LTSynthetic.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = LTSynthetic.cpp; sourceTree = "<group>"; };
+		25EF90052B497C7900D7C805 /* LTSynthetic.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = LTSynthetic.h; sourceTree = "<group>"; };
 		25EFC76B249567BF005DB0A6 /* IconsFontAwesome5.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = IconsFontAwesome5.h; sourceTree = "<group>"; };
 		25EFC76C249567BF005DB0A6 /* fa-solid-900.inc */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.pascal; path = "fa-solid-900.inc"; sourceTree = "<group>"; };
 		25F3471A24D2C7DE004574E7 /* parson.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = parson.h; sourceTree = "<group>"; };
@@ -307,6 +310,7 @@
 				259EC47925057815009B86F3 /* LTOpenGlider.cpp */,
 				2573631F22233CDA005210C5 /* LTOpenSky.cpp */,
 				2573631922233008005210C5 /* LTRealTraffic.cpp */,
+				25EF90032B497C6100D7C805 /* LTSynthetic.cpp */,
 				25ABEEFD219A1C2100F61413 /* LTVersion.cpp */,
 				254F278824EF230400CACCDA /* LTWeather.cpp */,
 				257363162222C879005210C5 /* Network.cpp */,
@@ -440,6 +444,7 @@
 				259EC47825057802009B86F3 /* LTOpenGlider.h */,
 				2573631C22233CCA005210C5 /* LTOpenSky.h */,
 				2573631B22233041005210C5 /* LTRealTraffic.h */,
+				25EF90052B497C7900D7C805 /* LTSynthetic.h */,
 				254F278724EF22FE00CACCDA /* LTWeather.h */,
 				257363182222C8E2005210C5 /* Network.h */,
 				25A095C32203B01300658AA8 /* SettingsUI.h */,
@@ -678,6 +683,7 @@
 				25ABEEFE219A1C2100F61413 /* LTVersion.cpp in Sources */,
 				254F278924EF230400CACCDA /* LTWeather.cpp in Sources */,
 				257363172222C879005210C5 /* Network.cpp in Sources */,
+				25EF90042B497C6100D7C805 /* LTSynthetic.cpp in Sources */,
 				25AE00D9213887AF00908E65 /* SettingsUI.cpp in Sources */,
 				25C59458207A296500E52073 /* TextIO.cpp in Sources */,
 			);

Src/DataRefs.cpp

@@ -571,6 +571,7 @@ DataRefs::dataRefDefinitionT DATA_REFS_LT[CNT_DATAREFS_LT] = {
     // channels, in ascending order of priority
     {"livetraffic/channel/futuredatachn/online",    DataRefs::LTGetInt, DataRefs::LTSetBool,        GET_VAR, false },
     {"livetraffic/channel/fore_flight/sender",      DataRefs::LTGetInt, DataRefs::LTSetBool,        GET_VAR, true, true },
+    {"livetraffic/channel/synthetic/intern",        DataRefs::LTGetInt, DataRefs::LTSetBool,        GET_VAR, true, true },
     {"livetraffic/channel/fscharter/online",        DataRefs::LTGetInt, DataRefs::LTSetBool,        GET_VAR, true, true },
     {"livetraffic/channel/open_glider/online",      DataRefs::LTGetInt, DataRefs::LTSetBool,        GET_VAR, true, true },
     {"livetraffic/channel/adsbhub/online",          DataRefs::LTGetInt, DataRefs::LTSetBool,        GET_VAR, true, true },
@@ -747,11 +748,12 @@ ILWrect (0, 400, 965, 0)
     for ( int& i: bChannel )
         i = false;
 
-    // enable OpenSky and OGN by default
+    // enable OpenSky, OGN, and Synthetic by default
     bChannel[DR_CHANNEL_OPEN_SKY_ONLINE         - DR_CHANNEL_FIRST] = true;
     bChannel[DR_CHANNEL_OPEN_SKY_AC_MASTERDATA  - DR_CHANNEL_FIRST] = true;
     bChannel[DR_CHANNEL_OPEN_SKY_AC_MASTERFILE  - DR_CHANNEL_FIRST] = true;
     bChannel[DR_CHANNEL_OPEN_GLIDER_NET         - DR_CHANNEL_FIRST] = true;
+    bChannel[DR_CHANNEL_SYNTHETIC               - DR_CHANNEL_FIRST] = true;
 
     // Clear the dataRefs arrays
     memset ( adrXP, 0, sizeof(adrXP));

Src/LTApt.cpp

@@ -2699,6 +2699,37 @@ positionTy LTAptFindRwy (const LTAircraft::FlightModel& _mdl,
 }
 
 
+// Find close-by startup position
+positionTy LTAptFindStartupLoc (const positionTy& pos,
+                                double maxDist,
+                                double* outDist)
+{
+    // Access to the list of airports is guarded by a lock
+    std::lock_guard<std::mutex> lock(mtxGMapApt);
+
+    // Which airport are we looking at?
+    Apt* pApt = LTAptFind(pos);
+    if (!pApt) {                        // not a position in any airport's bounding box
+        if (outDist) *outDist = NAN;
+        return positionTy();
+    }
+
+    // Let's go find!
+    if (std::isnan(maxDist))
+        maxDist = dataRefs.GetFdSnapTaxiDist_m() * 3;       // same as in SnapToTaxiway()
+    const StartupLoc* pSuL = pApt->FindStartupLoc(pos, maxDist, outDist);
+    if (!pSuL)
+        return positionTy();
+    else {
+        positionTy ret (pSuL->lat, pSuL->lon, NAN, NAN, pSuL->heading);
+        ret.f.bHeadFixed    = true;
+        ret.f.onGrnd        = GND_ON;
+        ret.f.specialPos    = SPOS_STARTUP;
+        return ret;
+    }
+}
+
+
 // Snaps the passed-in position to the nearest rwy or taxiway if appropriate
 bool LTAptSnap (LTFlightData& fd, dequePositionTy::iterator& posIter,
                 bool bInsertTaxiTurns)

Src/LTChannel.cpp

@@ -260,7 +260,7 @@ std::string LTChannel::GetStatusText () const
         return buf;
     }
     // Active, but not a channel for tracking data
-    if (GetChType() != CHT_TRACKING_DATA)   return "Active";
+    if (GetChType() >= CHT_MASTER_DATA)   return "Active";
     // An active source of tracking data...for how many aircraft?
     snprintf (buf, sizeof(buf), "Active, serving %d aircraft",
               GetNumAcServed());
@@ -304,10 +304,7 @@ std::list<LTACMasterdataChannel*> LTACMasterdataChannel::lstChn;
 // Constructor
 LTACMasterdataChannel::LTACMasterdataChannel (dataRefsLT ch, const char* chName) :
 LTOnlineChannel(ch, CHT_MASTER_DATA, chName)
-{
-    // Register myself as a master data channel
-    RegisterMasterDataChn(this);
-}
+{}
 
 /// Add the request to the set if not duplicate
 bool LTACMasterdataChannel::InsertRequest (const acStatUpdateTy& r)
@@ -468,6 +465,19 @@ void LTACMasterdataChannel::RegisterMasterDataChn (LTACMasterdataChannel* pChn)
     }
 }
 
+// Unregister a mster data channel
+void LTACMasterdataChannel::UnregisterMasterDataChn (LTACMasterdataChannel* pChn)
+{
+    try {
+        std::lock_guard<std::recursive_mutex> lock (mtxMaster);
+        // just remove the channel
+        lstChn.remove(pChn);
+    } catch(const std::system_error& e) {
+        LOG_MSG(logERR, ERR_LOCK_ERROR, "mtxMaster", e.what());
+    }
+}
+
+
 // Add request to fetch data
 bool LTACMasterdataChannel::RequestMasterData (const LTFlightData::FDKeyTy& keyAc,
                                                const std::string& callSign,
@@ -858,6 +868,7 @@ bool LTFlightDataEnable()
     listFDC.emplace_back(new ADSBHubConnection());
     listFDC.emplace_back(new OpenGliderConnection);
     listFDC.emplace_back(new FSCConnection);
+    listFDC.emplace_back(new SyntheticConnection);
     // load online master data connections
     listFDC.emplace_back(new OpenSkyAcMasterFile);
     listFDC.emplace_back(new OpenSkyAcMasterdata);