added finding path with A* and json file to know where character can walk

src/Character.cpp

@@ -22,8 +22,46 @@ void Character::loadAnimation(AnimationState state, const std::string& filename,
 
 void Character::setTarget(const Eigen::Vector3f& target,
                           std::function<void()> onArrived) {
-    walkTarget = target;
+    Eigen::Vector3f normalizedTarget(target.x(), 0.f, target.z());
+
+    const bool sameRequestedTarget =
+        (normalizedTarget - requestedWalkTarget).norm() <= TARGET_REPLAN_THRESHOLD;
+    const bool alreadyMovingToTarget =
+        !pathWaypoints.empty() || (walkTarget - normalizedTarget).norm() <= TARGET_REPLAN_THRESHOLD;
+    const bool stoppedAfterFailedPath =
+        pathWaypoints.empty() && (walkTarget - position).norm() <= TARGET_REPLAN_THRESHOLD;
+
+    if (!onArrived && sameRequestedTarget && (alreadyMovingToTarget || stoppedAfterFailedPath)) {
+        return;
+    }
+
+    requestedWalkTarget = normalizedTarget;
     onArrivedCallback = std::move(onArrived);
+
+    if (pathPlanner) {
+        pathWaypoints = pathPlanner(position, normalizedTarget);
+        currentWaypointIndex = 0;
+
+        if (!pathWaypoints.empty()) {
+            for (Eigen::Vector3f& waypoint : pathWaypoints) {
+                waypoint.y() = 0.f;
+            }
+            walkTarget = pathWaypoints.back();
+            return;
+        }
+
+        walkTarget = Eigen::Vector3f(position.x(), 0.f, position.z());
+        onArrivedCallback = nullptr;
+        return;
+    }
+
+    pathWaypoints.clear();
+    currentWaypointIndex = 0;
+    walkTarget = normalizedTarget;
+}
+
+void Character::setPathPlanner(PathPlanner planner) {
+    pathPlanner = std::move(planner);
 }
 
 AnimationState Character::resolveActiveState() const {
@@ -35,7 +73,12 @@ AnimationState Character::resolveActiveState() const {
 void Character::update(int64_t deltaMs) {
 	//std::cout << "update called with deltaMs: " << deltaMs << std::endl;
     // Move toward walk target on the XZ plane
-    Eigen::Vector3f toTarget = walkTarget - position;
+    Eigen::Vector3f activeTarget = walkTarget;
+    if (!pathWaypoints.empty() && currentWaypointIndex < pathWaypoints.size()) {
+        activeTarget = pathWaypoints[currentWaypointIndex];
+    }
+
+    Eigen::Vector3f toTarget = activeTarget - position;
     toTarget.y() = 0.f;
     float dist = toTarget.norm();
 
@@ -43,7 +86,7 @@ void Character::update(int64_t deltaMs) {
         Eigen::Vector3f dir = toTarget / dist;
         float moveAmount = walkSpeed * static_cast<float>(deltaMs) / 1000.f;
         if (moveAmount >= dist) {
-            position = walkTarget;
+            position = activeTarget;
             position.y() = 0.f;
         } else {
             position += dir * moveAmount;
@@ -60,7 +103,17 @@ void Character::update(int64_t deltaMs) {
         {
             currentState = AnimationState::STAND;
         }
-        if (onArrivedCallback) {
+
+        const bool hasNextWaypoint = !pathWaypoints.empty() && currentWaypointIndex + 1 < pathWaypoints.size();
+        if (hasNextWaypoint) {
+            ++currentWaypointIndex;
+        }
+        else {
+            pathWaypoints.clear();
+            currentWaypointIndex = 0;
+        }
+
+        if (!hasNextWaypoint && onArrivedCallback) {
             auto cb = std::move(onArrivedCallback);
             onArrivedCallback = nullptr;
             cb();