Interim windows build fix

[flightgear.git] / src / AIModel / AIMultiplayer.cxx

diff --git a/src/AIModel/AIMultiplayer.cxx b/src/AIModel/AIMultiplayer.cxx
index 30843b7c48b3643b3a16bc9705d0035e0fdd4cac..a4176b3a6d7076fb0e0726a2051384a2dc827251 100644 (file)
--- a/src/AIModel/AIMultiplayer.cxx
+++ b/src/AIModel/AIMultiplayer.cxx
@@ -26,6 +26,10 @@
 #endif
 
 #include <string>
+#include <stdio.h>
+
+#include <Main/globals.hxx>
+#include <Main/fg_props.hxx>
 
 #include "AIMultiplayer.hxx"
 
@@ -34,7 +38,7 @@ using std::string;
 // #define SG_DEBUG SG_ALERT
 
 FGAIMultiplayer::FGAIMultiplayer() :
-   FGAIBase(otMultiplayer, false)
+   FGAIBase(otMultiplayer, fgGetBool("/sim/multiplay/hot", false))
 {
    no_roll = false;
 
@@ -43,6 +47,8 @@ FGAIMultiplayer::FGAIMultiplayer() :
    mLagAdjustSystemSpeed = 10;
    mLastTimestamp = 0;
    lastUpdateTime = 0;
+   playerLag = 0.03;
+   compensateLag = 1;
 
 } 
 
@@ -97,7 +103,10 @@ SGRawValueMethods<FGAIMultiplayer, type>(*this, \
         AIMPRWProp(bool, AllowExtrapolation));
     tie("controls/lag-adjust-system-speed",
         AIMPRWProp(double, LagAdjustSystemSpeed));
-
+    tie("controls/player-lag",
+        AIMPRWProp(double, playerLag));
+    tie("controls/compensate-lag",
+        AIMPRWProp(int, compensateLag));
 
 #undef AIMPROProp
 #undef AIMPRWProp
@@ -139,7 +148,18 @@ void FGAIMultiplayer::update(double dt)
     mTimeOffsetSet = true;
     mTimeOffset = curentPkgTime - curtime - lag;
   } else {
-    double offset = curentPkgTime - curtime - lag;
+         double offset = 0.0;
+
+               //spectator mode, more late to be in the interpolation zone
+    if (compensateLag == 3) { offset = curentPkgTime -curtime -lag + playerLag;
+
+                 // old behaviour
+    } else if (compensateLag == 1) { offset = curentPkgTime - curtime - lag;
+
+    // using the prediction mode to display the mpaircraft in the futur/past with given playerlag value
+    //currently compensatelag = 2
+    } else { offset = curentPkgTime - curtime + 0.48*lag + playerLag;
+    }
     if ((!mAllowExtrapolation && offset + lag < mTimeOffset)
         || (offset - 10 > mTimeOffset)) {
       mTimeOffset = offset;
@@ -153,14 +173,27 @@ void FGAIMultiplayer::update(double dt)
       // arriving packets will pessimize the overall lag much more than
       // early packets will shorten the overall lag
       double sysSpeed;
-      if (err < 0) {
-        // Ok, we have some very late packets and nothing newer increase the
-        // lag by the given speedadjust
-        sysSpeed = mLagAdjustSystemSpeed*err;
-      } else {
-        // We have a too pessimistic display delay shorten that a small bit
-        sysSpeed = SGMiscd::min(0.1*err*err, 0.5);
-      }
+
+  //trying to slow the rudderlag phenomenon thus using more the prediction system
+  //if we are off by less than 1.5s, do a little correction, and bigger step above 1.5s
+         if (fabs(err) < 1.5) {
+               if (err < 0) {
+                 sysSpeed = mLagAdjustSystemSpeed*err*0.01;
+           } else {
+               sysSpeed = SGMiscd::min(0.5*err*err, 0.05);
+               }
+         } else {
+               if (err < 0) {
+
+                       // Ok, we have some very late packets and nothing newer increase the
+                       // lag by the given speedadjust
+                       sysSpeed = mLagAdjustSystemSpeed*err;
+               } else {
+                       // We have a too pessimistic display delay shorten that a small bit
+                       sysSpeed = SGMiscd::min(0.1*err*err, 0.5);
+          }
+         }
+
 
       // simple euler integration for that first order system including some
       // overshooting guard to prevent to aggressive system speeds
@@ -337,35 +370,38 @@ void FGAIMultiplayer::update(double dt)
     // and do some eom computation to guess that for now.
     FGExternalMotionData& motionInfo = it->second;
 
-    // The time to predict, limit to 5 seconds
+    // The time to predict, limit to 3 seconds
     double t = tInterp - motionInfo.time;
-    t = SGMisc<double>::min(t, 5);
+    t = SGMisc<double>::min(t, 3);
 
     SG_LOG(SG_AI, SG_DEBUG, "Multiplayer vehicle extrapolation: "
            "extrapolation time = " << t);
 
-    // Do a few explicit euler steps with the constant acceleration's
-    // This must be sufficient ...
+    // using velocity and acceleration to guess a parabolic position...
     ecPos = motionInfo.position;
     ecOrient = motionInfo.orientation;
     ecLinearVel = motionInfo.linearVel;
+    SGVec3d ecVel = toVec3d(ecOrient.backTransform(ecLinearVel));
     SGVec3f angularVel = motionInfo.angularVel;
-    while (0 < t) {
-      double h = 1e-1;
-      if (t < h)
-        h = t;
+    SGVec3d ecAcc = toVec3d(ecOrient.backTransform(motionInfo.linearAccel));
 
-      SGVec3d ecVel = toVec3d(ecOrient.backTransform(ecLinearVel));
-      ecPos += h*ecVel;
-      ecOrient += h*ecOrient.derivative(angularVel);
+       double normVel = norm(ecVel);
 
-      ecLinearVel += h*(cross(ecLinearVel, angularVel) + motionInfo.linearAccel);
-      angularVel += h*motionInfo.angularAccel;
-      
-      t -= h;
-    }
+       // not doing rotationnal prediction for small speed or rotation rate,
+       // to avoid agitated parked plane
+    if (( norm(angularVel) > 0.05 ) || ( normVel > 1.0 )) {
+               ecOrient += t*ecOrient.derivative(angularVel);
+       }
+
+       // not using acceleration for small speed, to have better parked planes
+       // note that anyway acceleration is not transmit yet by mp
+       if ( normVel > 1.0 ) {
+               ecPos += t*(ecVel + 0.5*t*ecAcc);
+       } else {
+               ecPos += t*(ecVel);
+       }
 
-    std::vector<FGPropertyData*>::const_iterator firstPropIt;
+       std::vector<FGPropertyData*>::const_iterator firstPropIt;
     std::vector<FGPropertyData*>::const_iterator firstPropItEnd;
     speed = norm(ecLinearVel) * SG_METER_TO_NM * 3600.0;
     firstPropIt = it->second.properties.begin();