Split follow path system with follow target position

game/components.c

@@ -17,7 +17,7 @@ ECS_COMPONENT_DECLARE(SpatialGridID);
 ECS_COMPONENT_DECLARE(Position);
 ECS_COMPONENT_DECLARE(Size);
 ECS_COMPONENT_DECLARE(Velocity);
-ECS_COMPONENT_DECLARE(Offset);
+ECS_COMPONENT_DECLARE(TargetPosition);
 ECS_COMPONENT_DECLARE(Rotation);
 ECS_COMPONENT_DECLARE(AngularVelocity);
 ECS_COMPONENT_DECLARE(SteeringOutput);
@@ -45,7 +45,7 @@ void initComponentIDs(ecs_world_t *ecs) {
     ECS_COMPONENT_DEFINE(ecs, Position);
     ECS_COMPONENT_DEFINE(ecs, Size);
     ECS_COMPONENT_DEFINE(ecs, Velocity);
-    ECS_COMPONENT_DEFINE(ecs, Offset);
+    ECS_COMPONENT_DEFINE(ecs, TargetPosition);
     ECS_COMPONENT_DEFINE(ecs, Rotation);
     ECS_COMPONENT_DEFINE(ecs, AngularVelocity);
     ECS_COMPONENT_DEFINE(ecs, SteeringOutput);

game/components.h

@@ -47,11 +47,11 @@ extern ECS_COMPONENT_DECLARE(Owner);
 typedef BzSpatialGridID SpatialGridID;
 extern ECS_COMPONENT_DECLARE(SpatialGridID);
 
-typedef Vector2 Position, Size, Velocity, Offset;
+typedef Vector2 Position, Size, Velocity, TargetPosition;
 extern ECS_COMPONENT_DECLARE(Position);
 extern ECS_COMPONENT_DECLARE(Size);
 extern ECS_COMPONENT_DECLARE(Velocity);
-extern ECS_COMPONENT_DECLARE(Offset);
+extern ECS_COMPONENT_DECLARE(TargetPosition);
 typedef f32 Rotation, AngularVelocity;
 extern ECS_COMPONENT_DECLARE(Rotation);
 extern ECS_COMPONENT_DECLARE(AngularVelocity);

game/main.c

@@ -150,7 +150,9 @@ bool init(void *userData) {
 
     ECS_SYSTEM(ECS, entityUpdateSpatialID, EcsOnUpdate, Position, Size, Velocity, SpatialGridID);
     ECS_SYSTEM(ECS, entityUpdateKinematic, EcsOnUpdate, Position, Rotation, Velocity, AngularVelocity, SteeringOutput);
-    ECS_SYSTEM(ECS, entityFollowPath, EcsOnUpdate, Position, Rotation, Velocity, AngularVelocity, SteeringOutput, Path);
+
+    ECS_SYSTEM(ECS, entityMoveToTarget, EcsOnUpdate, Position, Rotation, Velocity, TargetPosition, SteeringOutput);
+    ECS_SYSTEM(ECS, entityFollowPath, EcsOnUpdate, Path);
 
     ECS_SYSTEM(ECS, entityUpdateAnimationState, EcsOnUpdate, Velocity, AnimationType);
     ECS_SYSTEM(ECS, entityUpdateAnimation, EcsOnUpdate, Animation, TextureRegion);

game/systems.h

@@ -50,13 +50,17 @@ void entityUpdateSpatialID(ecs_iter_t *it);
 void entityUpdateKinematic(ecs_iter_t *it);
 
 /*
- * 0: Game (singleton) for object pool
  * 1: Position
  * 2: Rotation
  * 3: Velocity
- * 4: AngularVelocity
+ * 4: TargetPosition
  * 5: SteeringOutput
- * 6: Path
+ */
+void entityMoveToTarget(ecs_iter_t *it);
+
+/*
+ * 0: Game (singleton) for object pool
+ * 1: Path
  */
 void entityFollowPath(ecs_iter_t *it);
 

game/systems_entity.c

@@ -26,6 +26,10 @@ void entityPathRemoved(ecs_iter_t *it) {
     Path *path = ecs_field(it, Path, 1);
 
     for (i32 i = 0; i < it->count; i++) {
+        ecs_entity_t entity = it->entities[i];
+
+        ecs_remove(ECS, entity, TargetPosition);
+
         PathData *cur = path[i].paths;
         while (cur) {
             bzObjectPoolRelease(pool, cur);
@@ -115,17 +119,16 @@ void entityUpdateKinematic(ecs_iter_t *it) {
     }
 }
 
-void entityFollowPath(ecs_iter_t *it) {
-    const Game *game = ecs_singleton_get(ECS, Game);
+void entityMoveToTarget(ecs_iter_t *it) {
     Position *position = ecs_field(it, Position, 1);
     Rotation *rotation = ecs_field(it, Rotation, 2);
     Velocity *velocity = ecs_field(it, Velocity, 3);
-    AngularVelocity *angularVel = ecs_field(it, AngularVelocity , 4);
-    SteeringOutput *steering = ecs_field(it, SteeringOutput, 5);
-    Path *path = ecs_field(it, Path, 6);
+
+    TargetPosition *targetPos = ecs_field(it, TargetPosition, 4);
+    SteeringOutput *steering  = ecs_field(it, SteeringOutput, 5);
 
     for (i32 i = 0; i < it->count; i++) {
-        Position target = path[i].paths->waypoints[path[i].curWaypoint];
+        Position target = targetPos[i];
         steering[i].linear = Vector2Subtract(target, position[i]);
         f32 dst = Vector2LengthSqr(steering[i].linear);
         f32 maxAccel = 10.0f;
@@ -138,6 +141,23 @@ void entityFollowPath(ecs_iter_t *it) {
         }
 
         if (dst < 8.0f) {
+            // Arrived
+            ecs_remove(ECS, it->entities[i], TargetPosition);
+        }
+    }
+}
+
+void entityFollowPath(ecs_iter_t *it) {
+    const Game *game = ecs_singleton_get(ECS, Game);
+
+    Path *path = ecs_field(it, Path, 1);
+
+    for (i32 i = 0; i < it->count; i++) {
+        ecs_entity_t   entity = it->entities[i];
+        TargetPosition target = path[i].paths->waypoints[path[i].curWaypoint];
+
+        if (!ecs_has(ECS, entity, TargetPosition)) {
+            ecs_set_ptr(ECS, entity, TargetPosition, &target);
             path[i].curWaypoint++;
             if (path[i].curWaypoint >= path[i].paths->numWaypoints) {
                 path[i].curWaypoint = 0;