Fixed physical history replay, it appears to be bitwise identical now (#498).

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/branches/physics@10220 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/karts/kart.cpp

@@ -537,6 +537,7 @@ void Kart::reset()
     m_bounce_back_time     = 0.0f;
     m_skidding             = 1.0f;
     m_time_last_crash      = 0.0f;
+    m_speed                = 0.0f;
     m_view_blocked_by_plunger = 0.0f;
     
     if(m_terrain_sound)
@@ -575,9 +576,12 @@ void Kart::reset()
     if (m_skidmarks)
     {
         m_skidmarks->reset();
-        m_skidmarks->adjustFog( track_manager->getTrack( race_manager->getTrackName() )->isFogEnabled() );
+        const Track *track = 
+            track_manager->getTrack( race_manager->getTrackName() );
+        m_skidmarks->adjustFog(track->isFogEnabled() );
     }
     
+    m_vehicle->reset();
     for(int j=0; j<m_vehicle->getNumWheels(); j++)
     {
         m_vehicle->updateWheelTransform(j, true);

src/physics/btKart.cpp

@@ -95,6 +95,21 @@ btWheelInfo& btKart::addWheel(const btVector3& connectionPointCS,
 	return wheel;
 }   // addWheel
 
+// ----------------------------------------------------------------------------
+/** Resets the kart before a (re)start, to make sure all physics variable
+ *  are properly defined. This is especially important for physics replay.
+ */
+void btKart::reset()
+{
+    for(int i=0; i<getNumWheels(); i++)
+    {
+        btWheelInfo &wheel                     = m_wheelInfo[i];
+        wheel.m_raycastInfo.m_suspensionLength = 0;
+        wheel.m_rotation                       = 0;
+        updateWheelTransformsWS(wheel);
+    }
+}   // reset
+
 // ----------------------------------------------------------------------------
 const btTransform&	btKart::getWheelTransformWS( int wheelIndex ) const
 {

src/physics/btKart.hpp

@@ -88,6 +88,7 @@ public:
 
 	virtual ~btKart() ;
 
+    void reset();
 
 	///btActionInterface interface
 	virtual void updateAction( btCollisionWorld* collisionWorld, btScalar step)

src/race/history.cpp

@@ -24,6 +24,7 @@
 #include "io/file_manager.hpp"
 #include "modes/world.hpp"
 #include "karts/kart.hpp"
+#include "physics/physics.hpp"
 #include "race/race_manager.hpp"
 #include "tracks/track.hpp"
 #include "utils/constants.hpp"
@@ -131,10 +132,7 @@ void History::updateReplay(float dt)
         m_current = 0;
         // Note that for physics replay all physics parameters
         // need to be reset, e.g. velocity, ...
-        for(unsigned int i=0; i<world->getNumKarts(); i++)
-        {
-            world->getKart(i)->reset();
-        }
+        world->restartRace();
     }
     unsigned int num_karts = world->getNumKarts();
     for(unsigned k=0; k<num_karts; k++)