Add chase/evade behaviour

game/ai_actions.c

@@ -47,11 +47,89 @@ BzBTStatus aiResetElapsed(AIBlackboard *data, f32 dt) {
     return BZ_BT_SUCCESS;
 }
 
+#define ENEMY_NEARBY_DST 26.0f
+
 BzBTStatus aiIsEnemyNearby(AIBlackboard *data, f32 dt) {
+    if (data->seenEnemy && ecs_is_alive(ECS, data->seenEnemy)) {
+        Position enemyPos = *ecs_get(ECS, data->seenEnemy, Position);
+        Position pos = *ecs_get(ECS, data->entity, Position);
+
+        if (Vector2Distance(enemyPos, pos) > ENEMY_NEARBY_DST)
+            return BZ_BT_SUCCESS;
+    }
+
+    const f32 range = 20.0f;
+    Position pos = *ecs_get(ECS, data->entity, Position);
+    HitBox hb = *ecs_get(ECS, data->entity, HitBox);
+    Vector2 center = entityGetCenter(pos, hb);
+    Owner owner = *ecs_get(ECS, data->entity, Owner);
+
+    ecs_entity_t closest = 0;
+    f32 closestDst = 10000.0f;
+
+    Game *game = ecs_singleton_get_mut(ECS, Game);
+    BzSpatialGridIter it = bzSpatialGridIter(game->entityGrid,
+                                             center.x - range, center.y - range,
+                                             center.x + range, center.y + range);
+    while (bzSpatialGridQueryNext(&it)) {
+        ecs_entity_t other = *(ecs_entity_t *) it.data;
+        if (!ecs_is_alive(ECS, other)) continue;
+
+        if (!ecs_has(ECS, other, Owner) ||
+            ecs_get(ECS, other, Owner)->player == owner.player)
+            continue;
+
+        Position otherPos = *ecs_get(ECS, other, Position);
+        HitBox otherHB = *ecs_get(ECS, other, HitBox);
+        Vector2 otherCenter = entityGetCenter(otherPos, otherHB);
+
+        f32 dst = Vector2Distance(center, otherCenter);
+        if (dst > range) continue;
+
+        if (!bzTileMapCanRayCastLine(&game->map, center, otherCenter))
+            continue;
+
+        if (dst < closestDst) {
+            closest = other;
+            closestDst = dst;
+        }
+    }
+
+    if (closest) {
+        data->seenEnemy = closest;
+        return BZ_BT_SUCCESS;
+    }
+
     return BZ_BT_FAIL;
 }
-BzBTStatus aiEvadeTarget(AIBlackboard *data, f32 dt) {
-    return BZ_BT_SUCCESS;
+BzBTStatus aiAttackEnemy(AIBlackboard *data, f32 dt) {
+    if (!ecs_is_alive(ECS, data->seenEnemy))
+        return BZ_BT_SUCCESS;
+
+    Position enemyPos = *ecs_get(ECS, data->seenEnemy, Position);
+    Position pos = *ecs_get(ECS, data->entity, Position);
+
+    Vector2 dif = Vector2Subtract(enemyPos, pos);
+    // Overload steering
+    Steering *steering = ecs_get_mut(ECS, data->entity, Steering);
+    *steering = Vector2Normalize(dif);
+
+    return BZ_BT_RUNNING;
+
+}
+BzBTStatus aiEvadeEnemy(AIBlackboard *data, f32 dt) {
+    if (!ecs_is_alive(ECS, data->seenEnemy))
+        return BZ_BT_SUCCESS;
+
+    Position enemyPos = *ecs_get(ECS, data->seenEnemy, Position);
+    Position pos = *ecs_get(ECS, data->entity, Position);
+
+    Vector2 dif = Vector2Subtract(pos, enemyPos);
+    // Overload steering
+    Steering *steering = ecs_get_mut(ECS, data->entity, Steering);
+    *steering = Vector2Normalize(dif);
+
+    return BZ_BT_RUNNING;
 }
 
 BzBTStatus aiFindNextHarvestable(AIBlackboard *data, f32 dt) {