add ENTITY_NONE, ENTITY_AUTO reserved entity id & update player.set_entity(...)

src/constants.hpp

@@ -27,6 +27,7 @@ inline constexpr blockid_t BLOCK_OBSTACLE = 1;
 inline constexpr blockid_t BLOCK_STRUCT_AIR = 2;
 inline constexpr itemid_t ITEM_EMPTY = 0;
 inline constexpr entityid_t ENTITY_NONE = 0;
+inline constexpr entityid_t ENTITY_AUTO = std::numeric_limits<entityid_t>::max();
 
 inline constexpr int CHUNK_W = 16;
 inline constexpr int CHUNK_H = 256;

src/logic/scripting/lua/libs/libplayer.cpp

@@ -229,7 +229,9 @@ static int l_set_entity(lua::State* L) {
     if (player == nullptr) {
         return 0;
     }
-    if (auto entity = get_entity(L, 2)) {
+    if (lua::isnumber(L, 2)) {
+        player->setEntity(lua::tointeger(L, 2));
+    } else if (auto entity = get_entity(L, 2)) {
         player->setEntity(entity->getUID());
     }
     return 0;

src/objects/Player.cpp

@@ -62,7 +62,7 @@ Player::Player(
 Player::~Player() = default;
 
 void Player::updateEntity() {
-    if (eid == 0) {
+    if (eid == ENTITY_AUTO) {
         auto& def = level.content.entities.require("base:player");
         eid = level.entities->spawn(def, getPosition());
         if (auto entity = level.entities->get(eid)) {
@@ -73,7 +73,7 @@ void Player::updateEntity() {
         if (auto entity = level.entities->get(eid)) {
             entity->setPlayer(id);
         }
-    } else if (chunks->getChunkByVoxel(position)) {
+    } else if (chunks->getChunkByVoxel(position) && eid != ENTITY_NONE) {
         logger.error() << "player entity despawned or deleted; "
                           "will be respawned";
         eid = 0;

src/objects/Player.hpp

@@ -54,7 +54,7 @@ class Player : public Serializable {
     bool infiniteItems = true;
     bool instantDestruction = true;
     bool loadingChunks = true;
-    entityid_t eid;
+    entityid_t eid = ENTITY_AUTO;
     entityid_t selectedEid = 0;
 
     glm::vec3 rotation {};