X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=src%2FMain%2Fmain.cxx;h=8ac54aa5695984ea8d671a3e80b50954dad03b14;hb=b587400846111cc4d6713dcdd38b715c97923d5a;hp=8d1baa707cb01db5ac1332157e3c02cc36668d15;hpb=4529449b83b6287891ec4416c19960d0b9c5d4fe;p=flightgear.git

diff --git a/src/Main/main.cxx b/src/Main/main.cxx
index 8d1baa707..8ac54aa56 100644
--- a/src/Main/main.cxx
+++ b/src/Main/main.cxx
@@ -47,6 +47,7 @@
 #include <simgear/scene/model/animation.hxx>
 #include <simgear/scene/sky/sky.hxx>
 #include <simgear/structure/event_mgr.hxx>
+#include <simgear/props/AtomicChangeListener.hxx>
 #include <simgear/props/props.hxx>
 #include <simgear/timing/sg_time.hxx>
 #include <simgear/math/sg_random.h>
@@ -61,13 +62,14 @@
 #include <Model/acmodel.hxx>
 #include <Scenery/scenery.hxx>
 #include <Scenery/tilemgr.hxx>
+#include <Sound/fg_fx.hxx>
 #include <Sound/beacon.hxx>
 #include <Sound/morse.hxx>
+#include <Sound/fg_fx.hxx>
 #include <FDM/flight.hxx>
 #include <ATCDCL/ATCmgr.hxx>
 #include <ATCDCL/AIMgr.hxx>
 #include <Time/tmp.hxx>
-#include <Time/fg_timer.hxx>
 #include <Environment/environment_mgr.hxx>
 #include <GUI/new_gui.hxx>
 #include <MultiPlayer/multiplaymgr.hxx>
@@ -80,12 +82,12 @@
 #include "main.hxx"
 #include "util.hxx"
 #include "fg_init.hxx"
+#include "fg_os.hxx"
 #include "WindowSystemAdapter.hxx"
-
+#include <Main/viewer.hxx>
 
 static double real_delta_time_sec = 0.0;
 double delta_time_sec = 0.0;
-extern float init_volume;
 
 using namespace flightgear;
 
@@ -103,6 +105,9 @@ long global_multi_loop;
 SGTimeStamp last_time_stamp;
 SGTimeStamp current_time_stamp;
 
+void fgInitSoundManager();
+void fgSetNewSoundDevice(const char *);
+
 // The atexit() function handler should know when the graphical subsystem
 // is initialized.
 extern int _bootstrap_OSInit;
@@ -137,7 +142,8 @@ void fgUpdateTimeDepCalcs() {
         // We require just to have 50 meter scenery availabe around
         // the aircraft.
         double range = 1000.0;
-        if (globals->get_scenery()->scenery_available(lat, lon, range)) {
+        SGGeod geod = SGGeod::fromDeg(lon, lat);
+        if (globals->get_scenery()->scenery_available(geod, range)) {
             //SG_LOG(SG_FLIGHT, SG_INFO, "Finally initializing fdm");
             cur_fdm_state->init();
             if ( cur_fdm_state->get_bound() ) {
@@ -162,7 +168,7 @@ void fgUpdateTimeDepCalcs() {
                 // normal playback
                 replay_time->setDoubleValue( replay_time->getDoubleValue()
                                              + ( delta_time_sec
-                                               * fgGetInt("/sim/speed-up") ) );
+                                                 * fgGetInt("/sim/speed-up") ) );
             } else if ( replay_state->getIntValue() == 2 ) {
                 // paused playback (don't advance replay time)
             }
@@ -177,7 +183,6 @@ void fgUpdateTimeDepCalcs() {
         // do nothing, fdm isn't inited yet
     }
 
-    globals->get_model_mgr()->update(delta_time_sec);
     globals->get_aircraft_model()->update(delta_time_sec);
 
     // Update solar system
@@ -188,15 +193,6 @@ void fgUpdateTimeDepCalcs() {
 }
 
 
-void fgInitTimeDepCalcs( void ) {
-    // noop for now
-}
-
-
-static const double alt_adjust_ft = 3.758099;
-static const double alt_adjust_m = alt_adjust_ft * SG_FEET_TO_METER;
-
-
 // What should we do when we have nothing else to do?  Let's get ready
 // for the next move and update the display?
 static void fgMainLoop( void ) {
@@ -273,7 +269,7 @@ static void fgMainLoop( void ) {
         }
         current_time_stamp.stamp();
         /* Convert to ms */
-        double elapsed_us = current_time_stamp - last_time_stamp;
+        double elapsed_us = (current_time_stamp - last_time_stamp).toUSecs();
         if ( elapsed_us < frame_us ) {
             double requested_us = frame_us - elapsed_us;
             ulMilliSecondSleep ( (int)(requested_us / 1000.0) ) ;
@@ -286,7 +282,9 @@ static void fgMainLoop( void ) {
         // ulMilliSecondSleep() call is omitted this will peg the cpu
         // (which is just fine if FG is the only app you care about.)
         current_time_stamp.stamp();
-        while ( current_time_stamp - last_time_stamp < frame_us ) {
+        SGTimeStamp next_time_stamp = last_time_stamp;
+        next_time_stamp += SGTimeStamp::fromSec(1e-6*frame_us);
+        while ( current_time_stamp < next_time_stamp ) {
             current_time_stamp.stamp();
         }
     } else {
@@ -294,8 +292,7 @@ static void fgMainLoop( void ) {
         current_time_stamp.stamp();
     }
 
-    real_delta_time_sec
-        = double(current_time_stamp - last_time_stamp) / 1000000.0;
+    real_delta_time_sec = (current_time_stamp - last_time_stamp).toSecs();
 
     // Limit the time we need to spend in simulation loops
     // That means, if the /sim/max-simtime-per-frame value is strictly positive
@@ -312,15 +309,12 @@ static void fgMainLoop( void ) {
 
     // round the real time down to a multiple of 1/model-hz.
     // this way all systems are updated the _same_ amount of dt.
-    {
-        static double rem = 0.0;
-        real_delta_time_sec += rem;
-        double hz = model_hz;
-        double nit = floor(real_delta_time_sec*hz);
-        rem = real_delta_time_sec - nit/hz;
-        real_delta_time_sec = nit/hz;
-    }
-
+    static double reminder = 0.0;
+    real_delta_time_sec += reminder;
+    global_multi_loop = long(floor(real_delta_time_sec*model_hz));
+    global_multi_loop = SGMisc<long>::max(0, global_multi_loop);
+    reminder = real_delta_time_sec - double(global_multi_loop)/double(model_hz);
+    real_delta_time_sec = double(global_multi_loop)/double(model_hz);
 
     if (clock_freeze->getBoolValue() || wait_for_scenery) {
         delta_time_sec = 0;
@@ -334,8 +328,6 @@ static void fgMainLoop( void ) {
     fgSetDouble("/sim/time/delta-realtime-sec", real_delta_time_sec);
     fgSetDouble("/sim/time/delta-sec", delta_time_sec);
 
-    static long remainder = 0;
-    long elapsed;
 #ifdef FANCY_FRAME_COUNTER
     int i;
     double accum;
@@ -353,14 +345,14 @@ static void fgMainLoop( void ) {
     // probably move eventually
 
     /* printf("Before - ground = %.2f  runway = %.2f  alt = %.2f\n",
-           scenery.get_cur_elev(),
-           cur_fdm_state->get_Runway_altitude() * SG_FEET_TO_METER,
-           cur_fdm_state->get_Altitude() * SG_FEET_TO_METER); */
+       scenery.get_cur_elev(),
+       cur_fdm_state->get_Runway_altitude() * SG_FEET_TO_METER,
+       cur_fdm_state->get_Altitude() * SG_FEET_TO_METER); */
 
     /* printf("Adjustment - ground = %.2f  runway = %.2f  alt = %.2f\n",
-           scenery.get_cur_elev(),
-           cur_fdm_state->get_Runway_altitude() * SG_FEET_TO_METER,
-           cur_fdm_state->get_Altitude() * SG_FEET_TO_METER); */
+       scenery.get_cur_elev(),
+       cur_fdm_state->get_Runway_altitude() * SG_FEET_TO_METER,
+       cur_fdm_state->get_Altitude() * SG_FEET_TO_METER); */
 
     // cout << "Warp = " << globals->get_warp() << endl;
 
@@ -408,12 +400,6 @@ static void fgMainLoop( void ) {
                                 altitude->getDoubleValue() * SG_FEET_TO_METER,
                                 globals->get_time_params()->getJD() );
 
-    // Get elapsed time (in usec) for this past frame
-    elapsed = fgGetTimeInterval();
-    SG_LOG( SG_ALL, SG_DEBUG,
-            "Elapsed time interval is = " << elapsed
-            << ", previous remainder is = " << remainder );
-
     // Calculate frame rate average
 #ifdef FANCY_FRAME_COUNTER
     /* old fps calculation */
@@ -438,7 +424,7 @@ static void fgMainLoop( void ) {
         general.set_frame_rate( frames );
         fgSetInt("/sim/frame-rate", frames);
         SG_LOG( SG_ALL, SG_DEBUG,
-            "--> Frame rate is = " << general.get_frame_rate() );
+                "--> Frame rate is = " << general.get_frame_rate() );
         frames = 0;
     }
     last_time = t->get_cur_time();
@@ -460,39 +446,15 @@ static void fgMainLoop( void ) {
         globals->get_AI_mgr()->update(delta_time_sec);
 
     // Run flight model
-
-    // Calculate model iterations needed for next frame
-    elapsed += remainder;
-
-    global_multi_loop = (long)(((double)elapsed * 0.000001) * model_hz );
-    remainder = elapsed - ( (global_multi_loop*1000000) / model_hz );
-    SG_LOG( SG_ALL, SG_DEBUG,
-            "Model iterations needed = " << global_multi_loop
-            << ", new remainder = " << remainder );
-
-    // chop max iterations to something reasonable if the sim was
-    // delayed for an excessive amount of time
-    if ( global_multi_loop > 2.0 * model_hz ) {
-        global_multi_loop = (int)(2.0 * model_hz );
-        remainder = 0;
-    }
-
-    // flight model
-    if ( global_multi_loop > 0) {
+    if (0 < global_multi_loop) {
         // first run the flight model each frame until it is initialized
-        // then continue running each frame only after initial scenery load is complete.
+        // then continue running each frame only after initial scenery
+        // load is complete.
         fgUpdateTimeDepCalcs();
     } else {
         SG_LOG( SG_ALL, SG_DEBUG,
-            "Elapsed time is zero ... we're zinging" );
-    }
-
-    // Run audio scheduler
-#ifdef ENABLE_AUDIO_SUPPORT
-    if ( globals->get_soundmgr()->is_working() ) {
-        globals->get_soundmgr()->update( delta_time_sec );
+                "Elapsed time is zero ... we're zinging" );
     }
-#endif
 
     globals->get_subsystem_mgr()->update(delta_time_sec);
 
@@ -502,165 +464,54 @@ static void fgMainLoop( void ) {
     //   we may want to move this to its own class at some point
     //
     double visibility_meters = fgGetDouble("/environment/visibility-m");
-    FGViewer *current_view = globals->get_current_view();
-
     globals->get_tile_mgr()->prep_ssg_nodes( visibility_meters );
+
     // update tile manager for view...
-    SGLocation *view_location = globals->get_current_view()->getSGLocation();
-    globals->get_tile_mgr()->update( view_location, visibility_meters );
-    {
-        double lon = view_location->getLongitude_deg();
-        double lat = view_location->getLatitude_deg();
-        double alt = view_location->getAltitudeASL_ft() * SG_FEET_TO_METER;
-
-        // check if we can reuse the groundcache for that purpose.
-        double ref_time, r;
-        SGVec3d pt;
-        bool valid = cur_fdm_state->is_valid_m(&ref_time, pt.sg(), &r);
-        SGVec3d viewpos(globals->get_current_view()->get_view_pos());
-        if (valid && distSqr(viewpos, pt) < r*r) {
-            // Reuse the cache ...
-            double lev
-                = cur_fdm_state->get_groundlevel_m(lat*SGD_DEGREES_TO_RADIANS,
-                                                   lon*SGD_DEGREES_TO_RADIANS,
-                                                   alt + 2.0);
-            view_location->set_cur_elev_m( lev );
-        } else {
-            // Do full intersection test.
-            double lev;
-            if (globals->get_scenery()->get_elevation_m(lat, lon, alt+2, lev, 0))
-                view_location->set_cur_elev_m( lev );
-            else
-                view_location->set_cur_elev_m( -9999.0 );
-        }
-    }
+    SGVec3d viewPos = globals->get_current_view()->get_view_pos();
+    SGGeod geodViewPos = SGGeod::fromCart(viewPos);
+    globals->get_tile_mgr()->update(geodViewPos, visibility_meters);
 
     // run Nasal's settimer() loops right before the view manager
     globals->get_event_mgr()->update(delta_time_sec);
 
-    // update the view angle as late as possible, but before sound calculations
-    globals->get_viewmgr()->update(delta_time_sec);
+    // pick up model coordidnates that Nasal code may have set relative to the
+    // aircraft's
+    globals->get_model_mgr()->update(delta_time_sec);
 
-    // Do any I/O channel work that might need to be done (must come after viewmgr)
-    globals->get_io()->update(real_delta_time_sec);
+    // update the view angle as late as possible, but before sound calculations
+    globals->get_viewmgr()->update(real_delta_time_sec);
 
+    // Update the sound manager last so it can use the CPU while the GPU
+    // is processing the scenery (doubled the frame-rate for me) -EMH-
 #ifdef ENABLE_AUDIO_SUPPORT
-    // Right now we make a simplifying assumption that the primary
-    // aircraft is the source of all sounds and that all sounds are
-    // positioned in the aircraft base
-
-    static sgdVec3 last_listener_pos = {0, 0, 0};
-    static sgdVec3 last_model_pos = {0, 0, 0};
-
-    // get the orientation
-    const SGQuatd view_or = current_view->getViewOrientation();
-    SGQuatd surf_or = SGQuatd::fromLonLatDeg(
-        current_view->getLongitude_deg(), current_view->getLatitude_deg());
-    SGQuatd model_or = SGQuatd::fromYawPitchRollDeg(
-        globals->get_aircraft_model()->get3DModel()->getHeadingDeg(),
-        globals->get_aircraft_model()->get3DModel()->getPitchDeg(),
-        globals->get_aircraft_model()->get3DModel()->getRollDeg());
-
-    // get the up and at vector in the aircraft base
-    // (ok, the up vector is a down vector, but the coordinates
-    // are finally calculated in a left hand system and openal
-    // lives in a right hand system. Therefore we need to pass
-    // the down vector to get correct stereo sound.)
-    SGVec3d sgv_up = model_or.rotateBack(
-        surf_or.rotateBack(view_or.rotate(SGVec3d(0, 1, 0))));
-    sgVec3 up;
-    sgSetVec3(up, sgv_up[0], sgv_up[1], sgv_up[2]);
-    SGVec3d sgv_at = model_or.rotateBack(
-        surf_or.rotateBack(view_or.rotate(SGVec3d(0, 0, 1))));
-    sgVec3 at;
-    sgSetVec3(at, sgv_at[0], sgv_at[1], sgv_at[2]);
-
-    // get the location data for the primary FDM (now hardcoded to ac model)...
-    SGLocation *acmodel_loc = NULL;
-    acmodel_loc = (SGLocation *)globals->
-        get_aircraft_model()->get3DModel()->getSGLocation();
-
-    // Calculate speed of listener and model.  This code assumes the
-    // listener is either tracking the model at the same speed or
-    // stationary.
-
-    sgVec3 listener_vel, model_vel;
-    SGVec3d SGV3d_help;
-    sgdVec3 sgdv3_help;
-    sgdVec3 sgdv3_null = {0, 0, 0};
-
-    // the aircraft velocity as reported by the fdm (this will not
-    // vary or be affected by frame rates or timing jitter.)
-    sgVec3 fdm_vel_vec;
-    sgSetVec3( fdm_vel_vec,
-	       vn_fps->getDoubleValue() * SG_FEET_TO_METER,
-	       ve_fps->getDoubleValue() * SG_FEET_TO_METER,
-	       vd_fps->getDoubleValue() * SG_FEET_TO_METER );
-    double fdm_vel = sgLengthVec3(fdm_vel_vec);
-
-    // compute the aircraft velocity vector and scale it to the length
-    // of the fdm velocity vector.  This gives us a vector in the
-    // proper coordinate system, but also with the proper time
-    // invariant magnitude.
-    sgdSubVec3( sgdv3_help,
-                last_model_pos, acmodel_loc->get_absolute_view_pos());
-    sgdAddVec3( last_model_pos, sgdv3_null, acmodel_loc->get_absolute_view_pos());
-    SGV3d_help = model_or.rotateBack(
-        surf_or.rotateBack(SGVec3d(sgdv3_help[0],
-        sgdv3_help[1], sgdv3_help[2])));
-    sgSetVec3( model_vel, SGV3d_help[0], SGV3d_help[1], SGV3d_help[2]);
-
-    float vel = sgLengthVec3(model_vel);
-    if ( fabs(vel) > 0.0001 ) {
-	if ( fabs(fdm_vel / vel) > 0.0001 ) {
-	    sgScaleVec3( model_vel, fdm_vel / vel );
-	}
-    }
-
-    // check for moving or stationary listener (view position)
-    sgdSubVec3( sgdv3_help,
-                last_listener_pos, (double *)&current_view->get_view_pos());
-    sgdAddVec3( last_listener_pos,
-		sgdv3_null, (double *)&current_view->get_view_pos());
-
-    if ( sgdLengthVec3(sgdv3_help) > 0.00001 ) {
-	sgCopyVec3( listener_vel, model_vel );
+    static bool smgr_init = true;
+    if (smgr_init == true) {
+        static SGPropertyNode *sound_working = fgGetNode("/sim/sound/working");
+        if (sound_working->getBoolValue() == true) {
+            fgInitSoundManager();
+            smgr_init = false;
+        }
     } else {
-	sgSetVec3( listener_vel, 0.0, 0.0, 0.0 );
-    }
-
-    globals->get_soundmgr()->set_listener_vel( listener_vel );
-
-    // set positional offset for sources
-    sgdVec3 dsource_pos_offset;
-    sgdSubVec3( dsource_pos_offset,
-                (double*) &current_view->get_view_pos(),
-                acmodel_loc->get_absolute_view_pos() );
-    SGVec3d sgv_dsource_pos_offset = model_or.rotateBack(
-        surf_or.rotateBack(SGVec3d(dsource_pos_offset[0],
-        dsource_pos_offset[1], dsource_pos_offset[2])));
-
-    sgVec3 source_pos_offset;
-    sgSetVec3(source_pos_offset, sgv_dsource_pos_offset[0],
-        sgv_dsource_pos_offset[1], sgv_dsource_pos_offset[2]);
-
-    globals->get_soundmgr()->set_source_pos_all( source_pos_offset );
+        static SGPropertyNode *sound_enabled = fgGetNode("/sim/sound/enabled");
+        static SGSoundMgr *smgr = globals->get_soundmgr();
+        static bool smgr_enabled = true;
+
+        if (smgr_enabled != sound_enabled->getBoolValue()) {
+            if (smgr_enabled == true) { // request to suspend
+                smgr->suspend();
+                smgr_enabled = false;
+            } else {
+                smgr->resume();
+                smgr_enabled = true;
+            }
+        }
 
-    float orient[6];
-    for (int i = 0; i < 3; i++) {
-        orient[i] = sgv_at[i];
-        orient[i + 3] = sgv_up[i];
+        if (smgr_enabled == true) {
+            static SGPropertyNode *volume = fgGetNode("/sim/sound/volume");
+            smgr->set_volume(volume->getFloatValue());
+            smgr->update(delta_time_sec);
+        }
     }
-    globals->get_soundmgr()->set_listener_orientation( orient );
-
-    // set the velocity
-    // all sources are defined to be in the model
-    globals->get_soundmgr()->set_source_vel_all( model_vel );
-
-    // The listener is always positioned at the origin.
-    sgVec3 listener_pos;
-    sgSetVec3( listener_pos, 0.0, 0.0, 0.0 );
-    globals->get_soundmgr()->set_listener_pos( listener_pos );
 #endif
 
     // END Tile Manager udpates
@@ -668,15 +519,41 @@ static void fgMainLoop( void ) {
     if (!scenery_loaded && globals->get_tile_mgr()->isSceneryLoaded()
         && cur_fdm_state->get_inited()) {
         fgSetBool("sim/sceneryloaded",true);
-        fgSetFloat("/sim/sound/volume", init_volume);
-        globals->get_soundmgr()->set_volume(init_volume);
+        if (fgGetBool("/sim/sound/working")) {
+            globals->get_soundmgr()->activate();
+        }
+        globals->get_props()->tie("/sim/sound/devices/name",
+              SGRawValueFunctions<const char *>(0, fgSetNewSoundDevice), false);
     }
-
+    simgear::AtomicChangeListener::fireChangeListeners();
     fgRequestRedraw();
 
     SG_LOG( SG_ALL, SG_DEBUG, "" );
 }
 
+void fgInitSoundManager()
+{
+    SGSoundMgr *smgr = globals->get_soundmgr();
+
+    smgr->bind();
+    smgr->init(fgGetString("/sim/sound/device-name", NULL));
+
+    vector <const char*>devices = smgr->get_available_devices();
+    for (unsigned int i=0; i<devices.size(); i++) {
+        SGPropertyNode *p = fgGetNode("/sim/sound/devices/device", i, true);
+        p->setStringValue(devices[i]);
+    }
+    devices.clear();
+}
+
+void fgSetNewSoundDevice(const char *device)
+{
+    globals->get_soundmgr()->suspend();
+    globals->get_soundmgr()->stop();
+    globals->get_soundmgr()->init(device);
+    globals->get_soundmgr()->resume();
+}
+
 // Operation for querying OpenGL parameters. This must be done in a
 // valid OpenGL context, potentially in another thread.
 namespace
@@ -807,6 +684,7 @@ static void fgIdleFunction ( void ) {
 
     } else if ( idle_state == 5 ) {
         idle_state++;
+
         ////////////////////////////////////////////////////////////////////
         // Initialize the 3D aircraft model subsystem (has a dependency on
         // the scenery subsystem.)
@@ -858,10 +736,7 @@ static void fgIdleFunction ( void ) {
         // Sun diameter: 1,390,000 kilometers
         thesky->build( 80000.0, 80000.0,
                        463.3, 361.8,
-                       globals->get_ephem()->getNumPlanets(),
-                       globals->get_ephem()->getPlanets(),
-                       globals->get_ephem()->getNumStars(),
-                       globals->get_ephem()->getStars(),
+                       *globals->get_ephem(),
                        fgGetNode("/environment", true));
 
         // Initialize MagVar model
@@ -906,13 +781,13 @@ static void fgIdleFunction ( void ) {
             SG_LOG( SG_GENERAL, SG_INFO,
                 "Starting intro music: " << mp3file.str() );
 
-#if defined( __CYGWIN__ )
+# if defined( __CYGWIN__ )
             string command = "start /m `cygpath -w " + mp3file.str() + "`";
-#elif defined( WIN32 )
+# elif defined( _WIN32 )
             string command = "start /m " + mp3file.str();
-#else
+# else
             string command = "mpg123 " + mp3file.str() + "> /dev/null 2>&1";
-#endif
+# endif
 
             system ( command.c_str() );
         }
@@ -943,7 +818,9 @@ static void fgIdleFunction ( void ) {
                                          fgGetInt("/sim/startup/ysize") );
 
         fgSplashProgress("loading scenery objects");
-
+        int session = fgGetInt("/sim/session",0);
+        session++;
+        fgSetInt("/sim/session",session);
     }
 
     if ( idle_state == 1000 ) {
@@ -957,16 +834,17 @@ static void fgIdleFunction ( void ) {
 
 static void upper_case_property(const char *name)
 {
+    using namespace simgear;
     SGPropertyNode *p = fgGetNode(name, false);
     if (!p) {
         p = fgGetNode(name, true);
         p->setStringValue("");
     } else {
-        SGPropertyNode::Type t = p->getType();
-        if (t == SGPropertyNode::NONE || t == SGPropertyNode::UNSPECIFIED)
+        props::Type t = p->getType();
+        if (t == props::NONE || t == props::UNSPECIFIED)
             p->setStringValue("");
         else
-            assert(t == SGPropertyNode::STRING);
+            assert(t == props::STRING);
     }
     p->addChangeListener(new FGMakeUpperCase);
 }
@@ -1013,7 +891,7 @@ bool fgMainInit( int argc, char **argv ) {
     fgInitFGRoot(argc, argv);
 
     // Check for the correct base package version
-    static char required_version[] = "1.99.5";
+    static char required_version[] = "2.0.0";
     string base_version = fgBasePackageVersion();
     if ( !(base_version == required_version) ) {
         // tell the operator how to use this application