feat: scene ghosting, as the client streams a zone's scenes

The client keeps the scene under the player loaded, the scenes the zone
file's transitions connect to it, and the global scene
(Zone::StreamScenesAroundPosition 0x0108a3f0, TerrainManager::GetSceneAtPos
0x01069010, the connected scenes at 0x01066500; transitions naming a
missing scene dropped as Zone::FixupInvalidTransitions 0x010842e0 does).

- ZoneScenes (dCommon): the terrain's scene map lookup and the scene graph,
  shared by the world server and the dashboard.
- Objects remember the scene they were placed in (spawners pass theirs on).
- ghosting_scenes=1 (world config, off by default): players get the objects
  of their loaded scenes instead of the ones within the ghosting distances;
  objects from no scene go by the scene under them. Zones without a scene
  map keep distance ghosting.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dZoneManager/Level.cpp

@@ -19,8 +19,9 @@
 #include "dConfig.h"
 #include <ranges>
 
-Level::Level(Zone* parentZone, const std::string& filepath) {
+Level::Level(Zone* parentZone, const std::string& filepath, int32_t sceneID) {
 	m_ParentZone = parentZone;
+	m_SceneID = sceneID;
 
 	auto stream = Game::assetManager->GetFile(filepath.c_str());
 
@@ -40,8 +41,9 @@ Level::Level(Zone* parentZone, const std::string& filepath) {
 	LoadSceneObjects(levelFile.objects);
 }
 
-void Level::MakeSpawner(const SceneObject& obj) {
+void Level::MakeSpawner(const SceneObject& obj, int32_t sceneID) {
 	SpawnerInfo spawnInfo = SpawnerInfo();
+	spawnInfo.scene = sceneID;
 	SpawnerNode* node = new SpawnerNode();
 	spawnInfo.templateID = obj.lot;
 	spawnInfo.spawnerID = obj.id;
@@ -162,7 +164,7 @@ void Level::LoadSceneObjects(const std::vector<SceneObject>& objects) {
 		}
 
 		if (obj.lot == 176) { //Spawner
-			MakeSpawner(obj);
+			MakeSpawner(obj, m_SceneID);
 		} else { //Regular object
 			EntityInfo info;
 			info.spawnerID = 0;
@@ -172,6 +174,7 @@ void Level::LoadSceneObjects(const std::vector<SceneObject>& objects) {
 			info.rot = obj.rotation;
 			info.settings = obj.settings;
 			info.scale = obj.scale;
+			info.scene = m_SceneID;
 			Game::entityManager->CreateEntity(info);
 		}
 	}

dZoneManager/Level.h

@@ -15,13 +15,15 @@ public:
 	};
 
 public:
-	Level(Zone* parentZone, const std::string& filepath);
-	
-	static void MakeSpawner(const SceneObject& obj);
+	// sceneID: the scene id of the zone scene the file is (EntityInfo::scene of its objects)
+	Level(Zone* parentZone, const std::string& filepath, int32_t sceneID = -1);
+
+	static void MakeSpawner(const SceneObject& obj, int32_t sceneID = -1);
 
 	std::map<uint32_t, Header> m_ChunkHeaders;
 private:
 	Zone* m_ParentZone;
+	int32_t m_SceneID = -1;
 
 	//private functions:
 	void LoadSceneObjects(const std::vector<SceneObject>& objects);

dZoneManager/Spawner.cpp

@@ -24,6 +24,7 @@ Spawner::Spawner(const SpawnerInfo& info) {
 
 	m_EntityInfo.lot = m_Info.templateID;
 	m_EntityInfo.scale = m_Info.templateScale;
+	m_EntityInfo.scene = m_Info.scene;
 
 	m_Start = m_Info.noTimedSpawn;
 

dZoneManager/Spawner.h

@@ -70,6 +70,7 @@ struct SpawnerInfo {
 
 	bool emulated = false;
 	LWOOBJID emulator = LWOOBJID_EMPTY;
+	int32_t scene = -1; // the zone scene the spawner was placed in, passed to what it spawns (EntityInfo::scene)
 };
 
 class Spawner {

dZoneManager/Zone.cpp

@@ -66,6 +66,7 @@ void Zone::LoadZoneIntoMemory() {
 		m_SpawnpointRotation = zoneFile.spawnpointRotation;
 
 		m_SceneCount = zoneFile.scenes.size();
+		m_SceneGraph = ZoneScenes::SceneGraph(zoneFile.scenes, zoneFile.sceneTransitions);
 		for (auto& scene : zoneFile.scenes) {
 			LoadScene(std::move(scene));
 		}
@@ -198,7 +199,7 @@ uint32_t Zone::CalculateChecksum() const {
 void Zone::LoadLevelsIntoMemory() {
 	for (auto& [sceneID, scene] : m_Scenes) {
 		if (scene.level) continue;
-		scene.level = std::make_unique<Level>(this, m_ZonePath + scene.filename);
+		scene.level = std::make_unique<Level>(this, m_ZonePath + scene.filename, sceneID.GetSceneID());
 
 		if (scene.level->m_ChunkHeaders.empty()) continue;
 
@@ -207,6 +208,22 @@ void Zone::LoadLevelsIntoMemory() {
 	}
 }
 
+bool Zone::LoadSceneMap() {
+	if (m_ZoneRawPath.empty()) return false;
+	auto file = Game::assetManager->GetFile((m_ZonePath + m_ZoneRawPath).c_str());
+	if (!file) {
+		LOG("Could not open the terrain file %s for its scene map", (m_ZonePath + m_ZoneRawPath).c_str());
+		return false;
+	}
+	Raw::Raw raw;
+	if (!Raw::ReadRaw(file, raw)) {
+		LOG("Could not read the terrain file %s for its scene map", (m_ZonePath + m_ZoneRawPath).c_str());
+		return false;
+	}
+	m_SceneMap = ZoneScenes::SceneMap(raw);
+	return !m_SceneMap.Empty();
+}
+
 void Zone::AddRevision(LWOSCENEID sceneID, uint32_t revision) {
 	if (m_MapRevisions.find(sceneID) == m_MapRevisions.end()) {
 		m_MapRevisions.insert(std::make_pair(sceneID, revision));

dZoneManager/Zone.h

@@ -3,6 +3,7 @@
 #include "dZMCommon.h"
 #include "LDFFormat.h"
 #include "ZoneFile.h"
+#include "ZoneScenes.h"
 #include "tinyxml2.h"
 #include <string>
 #include <vector>
@@ -48,6 +49,12 @@ public:
 	const NiPoint3& GetSpawnPos() const { return m_Spawnpoint; }
 	const NiQuaternion& GetSpawnRot() const { return m_SpawnpointRotation; }
 
+	// Which scenes the client keeps loaded where (ZoneScenes); the scene map is empty unless LoadSceneMap read it
+	const ZoneScenes::SceneGraph& GetSceneGraph() const { return m_SceneGraph; }
+	const ZoneScenes::SceneMap& GetSceneMap() const { return m_SceneMap; }
+	// Reads the terrain file's scene map (for scene ghosting); false when the zone has none
+	bool LoadSceneMap();
+
 	void SetSpawnPos(const NiPoint3& pos) { m_Spawnpoint = pos; }
 	void SetSpawnRot(const NiQuaternion& rot) { m_SpawnpointRotation = rot; }
 
@@ -70,6 +77,8 @@ private:
 
 	std::map<LWOSCENEID, SceneRef> m_Scenes;
 	std::vector<SceneTransition> m_SceneTransitions;
+	ZoneScenes::SceneGraph m_SceneGraph;
+	ZoneScenes::SceneMap m_SceneMap;
 
 	uint32_t m_PathDataLength;
 	uint32_t m_PathChunkVersion;