Implement builder road construction with hex-edge auto-connection, winding rendering, and speed bonus

terrainmovementmanager.cpp

@@ -2,6 +2,7 @@
 #include "unitconfig.h"
 #include "pathfinder.h"
 #include "yamlparser.h"
+#include "gamemanager.h"
 #include <QDebug>
 #include <cmath>
 #include <algorithm>
@@ -300,15 +301,22 @@ float TerrainMovementManager::calculateStepCost(
         return -1.0f;
     }
 
+    float cost = baseCost;
     if (deltaH > 0.001f) {
         // Uphill penalty: going uphill increases movement cost
         float penalty = deltaH * m_config.uphillSlopeMultiplier;
-        return baseCost + penalty;
+        cost = baseCost + penalty;
     } else if (deltaH < -0.001f) {
         // Downhill bonus: going downhill decreases movement cost (negative penalty)
         float bonus = (-deltaH) * m_config.downhillSlopeBonusMultiplier;
-        return std::max(m_config.minStepCost, baseCost - bonus);
+        cost = std::max(m_config.minStepCost, baseCost - bonus);
     }
 
-    return baseCost;
+    // Road speed bonus: if traveling between connected road tiles, movement speed increases!
+    float roadMult = GameManager::instance().getRoadSpeedMultiplierBetween(fromX, fromY, toX, toY);
+    if (roadMult > 1.0f) {
+        cost /= roadMult;
+    }
+
+    return std::max(0.1f, cost);
 }