Fix distances when off-road, keep rescue to last on-road node

src/tracks/track_sector.cpp

@@ -41,6 +41,7 @@ void TrackSector::reset()
 {
     m_current_graph_node         = Graph::UNKNOWN_SECTOR;
     m_last_valid_graph_node      = Graph::UNKNOWN_SECTOR;
+    m_estimated_valid_graph_node = Graph::UNKNOWN_SECTOR;
     m_on_road                    = false;
     m_last_triggered_checkline   = -1;
 }   // reset
@@ -84,12 +85,15 @@ void TrackSector::update(const Vec3 &xyz, bool ignore_vertical)
     }
 
     // keep the current quad as the latest valid one IF the player has one
-    // of the required checklines
+    // of the required checklines AND is on road
+    // The on-road condition isn't required for the estimated valid node
+    // used for distances.
     const DriveNode* dn = DriveGraph::get()->getNode(m_current_graph_node);
     const std::vector<int>& checkline_requirements = dn->getChecklineRequirements();
 
     if (checkline_requirements.size() == 0)
     {
+        m_estimated_valid_graph_node = m_current_graph_node;
         if (m_on_road)
             m_last_valid_graph_node = m_current_graph_node;
     }
@@ -97,16 +101,17 @@ void TrackSector::update(const Vec3 &xyz, bool ignore_vertical)
     {
         for (unsigned int i=0; i<checkline_requirements.size(); i++)
         {
-            if (m_last_triggered_checkline == checkline_requirements[i])
+            if (m_last_triggered_checkline >= checkline_requirements[i])
             {
                 //has_prerequisite = true;
+                m_estimated_valid_graph_node = m_current_graph_node;
                 if (m_on_road)
                     m_last_valid_graph_node = m_current_graph_node;
                 break;
             }
         }
 
-        // TODO: show a message when we detect a user cheated.
+        // TODO: show a message when we detect a user missed a checkline.
 
     }
 
@@ -120,6 +125,12 @@ void TrackSector::update(const Vec3 &xyz, bool ignore_vertical)
         DriveGraph::get()->spatialToTrack(&m_latest_valid_track_coords, xyz,
             m_last_valid_graph_node);
     }
+
+    if (m_estimated_valid_graph_node != Graph::UNKNOWN_SECTOR)
+    {
+        DriveGraph::get()->spatialToTrack(&m_estimated_valid_track_coords, xyz,
+            m_estimated_valid_graph_node);
+    }
 }   // update
 
 // ----------------------------------------------------------------------------
@@ -139,6 +150,7 @@ void TrackSector::rescue()
                                             ->getPredecessor(0);
     m_last_valid_graph_node = DriveGraph::get()->getNode(m_current_graph_node)
                                                ->getPredecessor(0);
+    m_estimated_valid_graph_node = m_current_graph_node;
 }    // rescue
 
 // ----------------------------------------------------------------------------

src/tracks/track_sector.hpp

@@ -41,7 +41,10 @@ private:
     /** The graph node the object is on. */
     int  m_current_graph_node;
 
-    /** The index of the last valid graph node. */
+    /** The index of the estimated valid graph node. Used for distance. */
+    int  m_estimated_valid_graph_node;
+
+    /** The index of the last valid graph node. Used for rescue */
     int  m_last_valid_graph_node;
 
     /** The coordinates of this object on the track, i.e. how far from
@@ -49,6 +52,8 @@ private:
      *  of the center driveline. */
     Vec3 m_current_track_coords;
 
+    Vec3 m_estimated_valid_track_coords;
+
     Vec3 m_latest_valid_track_coords;
 
     /** True if the object is on the road (driveline), or not. */
@@ -64,10 +69,12 @@ public:
     float getRelativeDistanceToCenter() const;
     // ------------------------------------------------------------------------
     /** Returns how far the the object is from the start line. */
-    float getDistanceFromStart(bool account_for_checklines) const
+    float getDistanceFromStart(bool account_for_checklines, bool strict=false) const
     {
-        if (account_for_checklines)
+        if (account_for_checklines && strict)
             return m_latest_valid_track_coords.getZ();
+        else if (account_for_checklines)
+            return m_estimated_valid_track_coords.getZ();
         else
             return m_current_track_coords.getZ();
     }