Fixed #2742 - incorrect triggering if cannon line triggereed Caused

by not updating m_front_xyz when moving the kart (so an incorrect
position was used to detect checkline triggering).

src/karts/kart.cpp

@@ -427,6 +427,14 @@ void Kart::reset()
 
 }   // reset
 
+// -----------------------------------------------------------------------------
+void Kart::setXYZ(const Vec3& a)
+{
+    AbstractKart::setXYZ(a);
+    Vec3 front(0, 0, getKartLength()*0.5f);
+    m_xyz_front = getTrans()(front);
+}    // setXYZ
+
 // -----------------------------------------------------------------------------
 void Kart::increaseMaxSpeed(unsigned int category, float add_speed,
                             float engine_force, float duration,

src/karts/kart.hpp

@@ -286,6 +286,7 @@ public:
 
     virtual bool   playCustomSFX    (unsigned int type);
     virtual void   setController(Controller *controller);
+    virtual void   setXYZ(const Vec3& a);
 
     // ========================================================================
     // Powerup related functions.

src/karts/moveable.hpp

@@ -84,7 +84,7 @@ public:
     virtual void stopFlying();
 
     /** Sets the XYZ coordinates of the moveable. */
-    void setXYZ(const Vec3& a)
+    virtual void setXYZ(const Vec3& a)
     {
         m_transform.setOrigin(a);
         if(m_motion_state)

src/modes/world.cpp

@@ -781,6 +781,7 @@ void World::moveKartTo(AbstractKart* kart, const btTransform &transform)
     // Project kart to surface of track
     // This will set the physics transform
     Track::getCurrentTrack()->findGround(kart);
+    CheckManager::get()->resetAfterKartMove(kart);
 
 }   // moveKartTo
 

src/tracks/check_line.cpp

@@ -137,6 +137,13 @@ void CheckLine::reset(const Track &track)
     }
 }   // reset
 
+// ----------------------------------------------------------------------------
+void CheckLine::resetAfterKartMove(unsigned int kart_index)
+{
+    AbstractKart *kart = World::getWorld()->getKart(kart_index);
+    m_previous_position[kart_index] = kart->getXYZ();
+}   // resetAfterKartMove
+
 // ----------------------------------------------------------------------------
 void CheckLine::changeDebugColor(bool is_active)
 {
@@ -167,7 +174,7 @@ void CheckLine::changeDebugColor(bool is_active)
  *                  additional data.
  */
 bool CheckLine::isTriggered(const Vec3 &old_pos, const Vec3 &new_pos,
-    unsigned int kart_index)
+                            unsigned int kart_index)
 {
     World* w = World::getWorld();
     core::vector2df p=new_pos.toIrrVector2d();

src/tracks/check_line.hpp

@@ -77,6 +77,7 @@ public:
     virtual bool isTriggered(const Vec3 &old_pos, const Vec3 &new_pos,
                              unsigned int indx);
     virtual void reset(const Track &track);
+    virtual void resetAfterKartMove(unsigned int kart_index);
     virtual void changeDebugColor(bool is_active);
     /** Returns the actual line data for this checkpoint. */
     const core::line2df &getLine2D() const {return m_line;}

src/tracks/check_manager.cpp

@@ -22,6 +22,7 @@
 #include <algorithm>
 
 #include "io/xml_node.hpp"
+#include "karts/abstract_kart.hpp"
 #include "tracks/ambient_light_sphere.hpp"
 #include "tracks/check_cannon.hpp"
 #include "tracks/check_goal.hpp"
@@ -117,6 +118,19 @@ void CheckManager::reset(const Track &track)
         (*i)->reset(track);
 }   // reset
 
+// ----------------------------------------------------------------------------
+/** Called after a kart is moved (e.g. after a rescue) to reset any cached
+ *  check information. Without this an incorrect crossing of a checkline
+ *  could be triggered since a CheckLine stores the previous position).
+ *  \param kart_index Index of the kart that was moved.
+ */
+void CheckManager::resetAfterKartMove(AbstractKart *kart)
+{
+    std::vector<CheckStructure*>::iterator i;
+    for (i = m_all_checks.begin(); i != m_all_checks.end(); i++)
+        (*i)->resetAfterKartMove(kart->getWorldKartId());
+}   // resetAfterKartMove
+
 // ----------------------------------------------------------------------------
 /** Updates all animations. Called one per time step.
  *  \param dt Time since last call.

src/tracks/check_manager.hpp

@@ -25,6 +25,7 @@
 #include <string>
 #include <vector>
 
+class AbstractKart;
 class CheckStructure;
 class Track;
 class XMLNode;
@@ -48,6 +49,7 @@ public:
     void   load(const XMLNode &node);
     void   update(float dt);
     void   reset(const Track &track);
+    void   resetAfterKartMove(AbstractKart *kart);
     unsigned int getLapLineIndex() const;
     int    getChecklineTriggering(const Vec3 &from, const Vec3 &to) const;
     // ------------------------------------------------------------------------

src/tracks/check_structure.hpp

@@ -105,6 +105,7 @@ public:
                 CheckStructure(const XMLNode &node, unsigned int index);
     virtual    ~CheckStructure() {};
     virtual void update(float dt);
+    virtual void resetAfterKartMove(unsigned int kart_index) {};
     virtual void changeDebugColor(bool is_active) {}
     /** True if going from old_pos to new_pos crosses this checkline. This function
      *  is called from update (of the checkline structure).