Files
Destrum/destrum/src/Serialization/SceneSerializer.cpp
T

762 lines
29 KiB
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#include <destrum/Serialization/SceneSerializer.h>
#include <cmath>
#include <algorithm>
#include <fstream>
#include <limits>
#include <optional>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include <nlohmann/json.hpp>
#include <spdlog/spdlog.h>
#include <destrum/Scene/Scene.h>
#include <destrum/ObjectModel/Component.h>
#include <destrum/ObjectModel/GameObject.h>
#include <destrum/ObjectModel/ObjectId.h>
#include <destrum/ObjectModel/Transform.h>
#include <destrum/Assets/AssetReference.h>
#include <destrum/Components/Physics/Collider.h>
#include <destrum/Components/Physics/Rigidbody.h>
#include <destrum/FS/AssetFS.h>
#include <destrum/Graphics/Resources/PrimitiveMeshes.h>
#include <destrum/Serialization/ComponentFactory.h>
#include <destrum/Serialization/ComponentRegistry.h>
#include <destrum/Serialization/GlmJson.h>
using json = nlohmann::json;
namespace {
using ValidationError = std::optional<std::string>;
constexpr int CurrentSceneVersion = 2;
[[nodiscard]] bool IsFiniteNumber(const json& value) {
if (!value.is_number()) {
return false;
}
return std::isfinite(value.get<double>());
}
[[nodiscard]] bool IsFiniteArray(const json& value, std::size_t size) {
if (!value.is_array() || value.size() != size) {
return false;
}
for (const auto& element : value) {
if (!IsFiniteNumber(element)) {
return false;
}
}
return true;
}
// Returns the JSON path of the first NaN/Inf, nlohmann would write it as null
[[nodiscard]] std::optional<std::string> FindNonFinite(const json& value, const std::string& path) {
if (value.is_number_float()) {
if (!std::isfinite(value.get<double>())) {
return path;
}
return std::nullopt;
}
if (value.is_array()) {
for (std::size_t i = 0; i < value.size(); ++i) {
if (auto bad = FindNonFinite(value.at(i), path + "[" + std::to_string(i) + "]")) {
return bad;
}
}
return std::nullopt;
}
if (value.is_object()) {
for (auto it = value.begin(); it != value.end(); ++it) {
if (auto bad = FindNonFinite(it.value(), path + "." + it.key())) {
return bad;
}
}
}
return std::nullopt;
}
[[nodiscard]] std::string DescribeObject(std::size_t index, const json& objectJson) {
std::string description = "objects[" + std::to_string(index) + "]";
if (objectJson.is_object() && objectJson.contains("name") && objectJson.at("name").is_string()) {
description += " \"" + objectJson.at("name").get<std::string>() + "\"";
}
return description;
}
[[nodiscard]] ValidationError ValidateTransform(const json& objectJson, int version) {
if (!objectJson.contains("transform")) {
return std::nullopt;
}
const auto& transform = objectJson.at("transform");
if (!transform.is_object()) {
return "transform must be an object";
}
// Version 1 wrote an empty placeholder transform object.
if (version <= 1 && transform.empty()) {
return std::nullopt;
}
for (const char* key : {"position", "rotation", "scale"}) {
if (!transform.contains(key)) {
return std::string{"transform is missing \""} + key + "\"";
}
}
if (!IsFiniteArray(transform.at("position"), 3)) {
return "transform.position must be 3 finite numbers";
}
if (!IsFiniteArray(transform.at("scale"), 3)) {
return "transform.scale must be 3 finite numbers";
}
const auto& rotation = transform.at("rotation");
if (!IsFiniteArray(rotation, 3) && !IsFiniteArray(rotation, 4)) {
return "transform.rotation must be 3 (euler) or 4 (quaternion) finite numbers";
}
return std::nullopt;
}
[[nodiscard]] ValidationError ValidateComponents(const json& objectJson) {
if (!objectJson.contains("components")) {
return std::nullopt;
}
const auto& components = objectJson.at("components");
if (!components.is_array()) {
return "components must be an array";
}
for (std::size_t i = 0; i < components.size(); ++i) {
const auto& componentJson = components.at(i);
const std::string where = "components[" + std::to_string(i) + "]";
if (!componentJson.is_object() || !componentJson.contains("type") ||
!componentJson.at("type").is_string()) {
return where + " must be an object with a string \"type\"";
}
const std::string type = componentJson.at("type").get<std::string>();
const std::string named = where + " " + type;
if (componentJson.contains("enabled") && !componentJson.at("enabled").is_boolean()) {
return named + ": \"enabled\" must be a boolean";
}
if (componentJson.contains("data")) {
const auto& data = componentJson.at("data");
if (!data.is_object()) {
return named + ": \"data\" must be an object, got " + std::string{data.type_name()};
}
if (auto bad = FindNonFinite(data, "data")) {
return named + ": " + *bad + " is not a finite number";
}
}
if (!ComponentFactory::IsRegistered(type)) {
return named + ": unknown component type";
}
}
return std::nullopt;
}
[[nodiscard]] ValidationError ValidateSceneJson(const json& root) {
if (!root.is_object()) {
return "root must be an object";
}
if (!root.contains("objects") || !root.at("objects").is_array()) {
return "root must contain an \"objects\" array";
}
if (root.contains("name") && !root.at("name").is_string()) {
return "\"name\" must be a string";
}
int version = 1;
if (root.contains("version")) {
if (!root.at("version").is_number_integer()) {
return "\"version\" must be an integer";
}
version = root.at("version").get<int>();
if (version < 1 || version > CurrentSceneVersion) {
return "unsupported scene version " + std::to_string(version);
}
}
if (root.contains("currentCamera") && !root.at("currentCamera").is_number_unsigned()) {
return "\"currentCamera\" must be an object id";
}
std::unordered_set<ObjectId> ids;
std::unordered_map<ObjectId, ObjectId> parents;
std::unordered_map<ObjectId, std::string> descriptions;
const auto& objects = root.at("objects");
for (std::size_t index = 0; index < objects.size(); ++index) {
const auto& objectJson = objects.at(index);
const std::string where = DescribeObject(index, objectJson);
if (!objectJson.is_object()) {
return where + " must be an object";
}
if (!objectJson.contains("id") || !objectJson.at("id").is_number_unsigned()) {
return where + " must have a non-negative integer \"id\"";
}
const ObjectId id = objectJson.at("id").get<ObjectId>();
if (id == InvalidObjectId || id >= std::numeric_limits<ObjectId>::max() - 1) {
return where + " uses reserved id " + std::to_string(id);
}
if (!ids.insert(id).second) {
return where + " reuses id " + std::to_string(id);
}
descriptions.emplace(id, where);
if (objectJson.contains("name") && !objectJson.at("name").is_string()) {
return where + ": \"name\" must be a string";
}
if (objectJson.contains("active") && !objectJson.at("active").is_boolean()) {
return where + ": \"active\" must be a boolean";
}
if (auto error = ValidateTransform(objectJson, version)) {
return where + ": " + *error;
}
ObjectId parent = InvalidObjectId;
if (objectJson.contains("parent")) {
if (!objectJson.at("parent").is_number_unsigned()) {
return where + ": \"parent\" must be an object id";
}
parent = objectJson.at("parent").get<ObjectId>();
}
if (parent == id) {
return where + " is its own parent";
}
parents.emplace(id, parent);
if (auto error = ValidateComponents(objectJson)) {
return where + " " + *error;
}
}
for (const auto& [id, parent] : parents) {
if (parent != InvalidObjectId && !ids.contains(parent)) {
return descriptions.at(id) + " has missing parent id " + std::to_string(parent);
}
std::unordered_set<ObjectId> visited;
ObjectId current = id;
while (current != InvalidObjectId) {
if (!visited.insert(current).second) {
return descriptions.at(id) + " is part of a parent cycle";
}
const auto parentIt = parents.find(current);
if (parentIt == parents.end()) {
return descriptions.at(id) + " has missing ancestor id " + std::to_string(current);
}
current = parentIt->second;
}
}
return std::nullopt;
}
[[nodiscard]] bool AssetFileExists(const std::string& path) {
if (path.empty() || PrimitiveMeshes::IsPrimitiveKey(path)) {
return true;
}
std::filesystem::path fullPath;
if (path.find("://") != std::string::npos) {
try {
fullPath = AssetFS::GetInstance().GetFullPath(path);
} catch (const std::exception&) {
return false;
}
} else {
fullPath = path;
}
return std::filesystem::exists(fullPath);
}
void ValidateAssetReferences(const json& root, const std::filesystem::path& scenePath) {
const auto report = [&](const std::string& objectName, const std::string& detail) {
spdlog::warn("Scene asset warning ({}): {} references \"{}\" which could not be found",
scenePath.string(), objectName, detail);
};
for (const auto& objectJson : root.at("objects")) {
const std::string objectName = objectJson.value("name", "GameObject");
if (!objectJson.contains("components")) {
continue;
}
for (const auto& componentJson : objectJson.at("components")) {
if (!componentJson.contains("data")) {
continue;
}
const auto& data = componentJson.at("data");
// MeshRendererComponent: meshKey / materialKey are asset cache keys.
for (const char* key : {"meshKey", "materialKey"}) {
if (data.contains(key) && data.at(key).is_string()) {
const std::string cacheKey = data.at(key).get<std::string>();
if (cacheKey.empty()) continue;
const auto asset = AssetReference::fromCacheKey(cacheKey);
// Runtime-only keys like "BulbMaterial#2" are not file paths
const bool looksLikePath = asset &&
asset->path.find_first_of(":/\\") != std::string::npos;
if (looksLikePath && !AssetFileExists(asset->path)) {
report(objectName, cacheKey);
}
}
}
// Generic: any nested object with a "path" field is an AssetReference.
std::function<void(const json&)> walk = [&](const json& node) {
if (node.is_object()) {
if (node.contains("path") && node.at("path").is_string()) {
const std::string path = node.at("path").get<std::string>();
if (!path.empty() && !AssetFileExists(path)) {
report(objectName, path);
}
}
for (auto it = node.begin(); it != node.end(); ++it) {
walk(it.value());
}
} else if (node.is_array()) {
for (const auto& element : node) {
walk(element);
}
}
};
walk(data);
}
}
}
[[nodiscard]] bool WriteFileAtomically(const std::filesystem::path& path, const std::string& contents) {
std::filesystem::path tempPath = path;
tempPath += ".tmp";
{
std::ofstream file(tempPath, std::ios::binary | std::ios::trunc);
if (!file.is_open()) {
spdlog::error("Failed to open scene file for writing: {}", tempPath.string());
return false;
}
file << contents;
file.flush();
if (!file.good()) {
spdlog::error("Failed to write scene file: {}", tempPath.string());
file.close();
std::error_code ignored;
std::filesystem::remove(tempPath, ignored);
return false;
}
}
std::error_code error;
std::filesystem::rename(tempPath, path, error);
if (error) {
spdlog::error("Failed to replace scene file {}: {}", path.string(), error.message());
std::error_code ignored;
std::filesystem::remove(tempPath, ignored);
return false;
}
return true;
}
}
bool SceneSerializer::Save(Scene& scene, const std::filesystem::path& path) {
if (scene.IsIterating()) {
spdlog::error("Cannot save a scene during an update or render phase: {}", scene.GetName());
return false;
}
RegisterEngineComponents();
try {
scene.CommitPendingAdditions();
} catch (const std::exception& exception) {
spdlog::error("Failed to commit scene additions before save: {}", exception.what());
return false;
}
json root;
root["version"] = CurrentSceneVersion;
root["name"] = scene.GetName();
root["objects"] = json::array();
if (scene.m_CurrentCameraId != InvalidObjectId) {
root["currentCamera"] = scene.m_CurrentCameraId;
}
const SceneEnvironment& environment = scene.GetEnvironment();
root["environment"] = {
{"ambientColor", environment.ambientColor},
{"ambientIntensity", environment.ambientIntensity},
{"fogColor", environment.fogColor},
{"fogDensity", environment.fogDensity},
{"skyboxRotationSpeed", environment.skyboxRotationSpeed},
{"skyboxRotation", environment.skyboxRotation},
};
for (const auto& objectPtr : scene.GetObjects()) {
if (!objectPtr || objectPtr->IsBeingDestroyed()) {
continue;
}
const GameObject& object = *objectPtr;
if (object.GetComponent<Rigidbody>() != nullptr &&
object.GetComponent<Collider>() == nullptr) {
spdlog::error("Cannot save object with a Rigidbody but no Collider: {}", object.GetName());
return false;
}
const Transform& transform = object.GetTransform();
json objectJson;
objectJson["id"] = object.GetId();
objectJson["name"] = object.GetName();
objectJson["active"] = object.IsActive();
objectJson["transform"] = {
{"position", transform.GetLocalPosition()},
{"rotation", transform.GetLocalRotation()},
{"scale", transform.GetLocalScale()}
};
const Transform* parent = transform.GetParent();
objectJson["parent"] = parent != nullptr && parent->GetOwner() != nullptr &&
parent->GetOwner()->GetScene() == &scene &&
!parent->GetOwner()->IsBeingDestroyed()
? parent->GetOwner()->GetId()
: InvalidObjectId;
objectJson["components"] = json::array();
for (const auto& componentPtr : object.GetComponents()) {
if (!componentPtr || componentPtr->IsBeingDestroyed()) {
continue;
}
const Component& component = *componentPtr;
json data;
try {
data = component.Serialize();
} catch (const std::exception& exception) {
spdlog::error("Failed to serialize {} on \"{}\": {}",
component.GetTypeName(), object.GetName(), exception.what());
return false;
}
if (data.is_null()) {
data = json::object();
}
if (auto bad = FindNonFinite(data, "data")) {
spdlog::error("Cannot save {} on \"{}\": {} is NaN or Inf",
component.GetTypeName(), object.GetName(), *bad);
return false;
}
objectJson["components"].push_back({
{"type", component.GetTypeName()},
{"enabled", component.isEnabled()},
{"data", std::move(data)}
});
}
root["objects"].push_back(std::move(objectJson));
}
if (auto bad = FindNonFinite(root, "scene")) {
spdlog::error("Cannot save scene \"{}\": {} is NaN or Inf", scene.GetName(), *bad);
return false;
}
// Refuse to write anything Load would reject
if (auto error = ValidateSceneJson(root)) {
spdlog::error("Cannot save scene \"{}\", it would not load back: {}", scene.GetName(), *error);
return false;
}
std::string contents;
try {
contents = root.dump(4);
} catch (const std::exception& exception) {
spdlog::error("Failed to encode scene \"{}\": {}", scene.GetName(), exception.what());
return false;
}
return WriteFileAtomically(path, contents);
}
SceneSerializer::LoadResult SceneSerializer::LoadSceneFile(const std::filesystem::path& path) {
LoadResult result;
RegisterEngineComponents();
std::ifstream file(path);
if (!file.is_open()) {
result.errorMessage = "Failed to open scene file for reading: " + path.string();
spdlog::error("{}", result.errorMessage);
return result;
}
try {
file >> result.root;
} catch (const std::exception& exception) {
result.errorMessage = "Failed to parse scene file " + path.string() + ": " + exception.what();
spdlog::error("{}", result.errorMessage);
return result;
}
if (auto error = ValidateSceneJson(result.root)) {
result.errorMessage = "Invalid scene data in " + path.string() + ": " + *error;
spdlog::error("{}", result.errorMessage);
return result;
}
ValidateAssetReferences(result.root, path);
result.success = true;
return result;
}
bool SceneSerializer::ConstructScene(Scene& scene, LoadResult& result,
std::function<void(float)> progressCallback) {
if (scene.IsIterating()) {
spdlog::error("Cannot load a scene during an update or render phase: {}", scene.GetName());
return false;
}
if (!result.success) {
spdlog::error("Cannot construct scene from a failed load result: {}", result.errorMessage);
return false;
}
if (scene.IsBeingUnloaded()) {
spdlog::error("Cannot load a scene that is being unloaded: {}", scene.GetName());
return false;
}
RegisterEngineComponents();
if (progressCallback) progressCallback(0.35f);
const json& root = result.root;
// Build the replacement separately. The current scene is not touched
// until all objects, transforms, and components have loaded successfully.
// No physics world is created for the staging scene - physics bodies are
// registered directly in the live scene's world once loading succeeds.
Scene stagingScene(scene.GetName(), nullptr);
std::unordered_map<ObjectId, GameObject*> idMap;
std::vector<const json*> objectJsonList;
std::vector<GameObject*> registeredObjects;
std::string context = "scene";
try {
for (const auto& objectJson : root.at("objects")) {
const ObjectId id = objectJson.at("id").get<ObjectId>();
const std::string name = objectJson.value("name", "GameObject");
const bool active = objectJson.value("active", true);
// File ids are local to the file, every loaded object gets a fresh runtime id
GameObject* object = stagingScene.CreateGameObject(name);
object->SetActive(active);
idMap.emplace(id, object);
objectJsonList.push_back(&objectJson);
}
if (progressCallback) progressCallback(0.4f);
// Move objects from pending to objects list without physics registration
// (staging scene has no physics world).
for (auto& pending : stagingScene.m_pendingAdditions) {
if (pending) {
stagingScene.m_objects.emplace_back(std::move(pending));
}
}
stagingScene.m_pendingAdditions.clear();
for (const json* objectJson : objectJsonList) {
const ObjectId id = objectJson->at("id").get<ObjectId>();
GameObject* object = idMap.at(id);
context = "\"" + object->GetName() + "\" transform";
if (objectJson->contains("transform") &&
!objectJson->at("transform").empty()) {
const auto& transformJson = objectJson->at("transform");
const auto& rotation = transformJson.at("rotation");
object->GetTransform().SetLocalPosition(transformJson.at("position").get<glm::vec3>());
if (rotation.size() == 4) {
object->GetTransform().SetLocalRotation(rotation.get<glm::quat>());
} else {
// Version 1 scene files used three Euler angles in
// degrees. Continue reading that format safely.
object->GetTransform().SetLocalRotation(rotation.get<glm::vec3>());
}
object->GetTransform().SetLocalScale(transformJson.at("scale").get<glm::vec3>());
}
const ObjectId parentId = objectJson->value("parent", InvalidObjectId);
if (parentId != InvalidObjectId) {
object->GetTransform().SetParent(&idMap.at(parentId)->GetTransform(), false);
}
}
if (progressCallback) progressCallback(0.5f);
for (const json* objectJson : objectJsonList) {
GameObject* object = idMap.at(objectJson->at("id").get<ObjectId>());
if (!objectJson->contains("components")) {
continue;
}
for (const auto& componentJson : objectJson->at("components")) {
const std::string type = componentJson.at("type").get<std::string>();
context = type + " on \"" + object->GetName() + "\"";
Component* component = ComponentFactory::Create(type, *object);
if (component == nullptr) {
throw std::runtime_error("unknown component type");
}
component->SetEnabled(componentJson.value("enabled", true));
if (componentJson.contains("data")) {
component->Deserialize(componentJson.at("data"));
}
}
}
if (progressCallback) progressCallback(0.6f);
for (const auto& objectPtr : stagingScene.GetObjects()) {
if (!objectPtr) {
continue;
}
for (const auto& componentPtr : objectPtr->GetComponents()) {
if (componentPtr) {
context = componentPtr->GetTypeName() + " on \"" + objectPtr->GetName() + "\" references";
componentPtr->ResolveReferences(idMap);
}
}
}
if (progressCallback) progressCallback(0.7f);
// Register the replacement bodies in the live physics world before
// touching the current scene. If any body fails, the old scene and
// its physics state can remain intact.
for (const auto& objectPtr : stagingScene.GetObjects()) {
if (objectPtr) {
context = "\"" + objectPtr->GetName() + "\" physics";
if (objectPtr->GetComponent<Rigidbody>() != nullptr &&
objectPtr->GetComponent<Collider>() == nullptr) {
throw std::runtime_error("Rigidbody requires a collider");
}
scene.GetPhysics().RegisterGameObject(*objectPtr);
registeredObjects.push_back(objectPtr.get());
}
}
if (progressCallback) progressCallback(0.8f);
} catch (const std::exception& exception) {
spdlog::error("Failed to load scene ({}): {}", context, exception.what());
for (GameObject* object : registeredObjects) {
if (object != nullptr) {
scene.GetPhysics().UnregisterGameObject(*object);
}
}
stagingScene.RemoveAll();
return false;
}
const bool bindingsWereLoaded = scene.m_bindingsLoaded;
scene.UnloadBindings();
scene.RemoveAll();
scene.m_objects = std::move(stagingScene.m_objects);
scene.m_pendingAdditions = std::move(stagingScene.m_pendingAdditions);
if (root.contains("name")) {
scene.m_name = root.at("name").get<std::string>();
}
scene.m_SelectedObjectId = InvalidObjectId;
scene.m_CurrentCameraId = InvalidObjectId;
if (const ObjectId cameraFileId = root.value("currentCamera", InvalidObjectId); cameraFileId != InvalidObjectId) {
if (const auto it = idMap.find(cameraFileId); it != idMap.end()) {
scene.m_CurrentCameraId = it->second->GetId();
} else {
spdlog::warn("Scene \"{}\" current camera id {} does not exist, ignoring it",
scene.m_name, cameraFileId);
}
}
scene.m_Environment = SceneEnvironment{};
if (root.contains("environment") && root.at("environment").is_object()) {
const auto& data = root.at("environment");
SceneEnvironment& environment = scene.m_Environment;
try {
environment.ambientColor = data.value("ambientColor", environment.ambientColor);
environment.ambientIntensity = data.value("ambientIntensity", environment.ambientIntensity);
environment.fogColor = data.value("fogColor", environment.fogColor);
environment.fogDensity = data.value("fogDensity", environment.fogDensity);
environment.skyboxRotationSpeed = data.value("skyboxRotationSpeed", environment.skyboxRotationSpeed);
environment.skyboxRotation = data.value("skyboxRotation", environment.skyboxRotation);
} catch (const std::exception& exception) {
spdlog::warn("Scene \"{}\" has invalid environment settings, using defaults: {}",
scene.m_name, exception.what());
environment = SceneEnvironment{};
}
}
if (progressCallback) progressCallback(0.9f);
for (const auto& object : scene.m_objects) {
if (object) {
object->SetScene(&scene);
}
}
for (const auto& object : scene.m_pendingAdditions) {
if (object) {
object->SetScene(&scene);
}
}
if (bindingsWereLoaded) {
try {
scene.LoadBindings();
} catch (const std::exception& exception) {
spdlog::error("Scene \"{}\" loaded but its bindings failed: {}", scene.m_name, exception.what());
}
}
if (progressCallback) progressCallback(1.0f);
return true;
}
bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path,
std::function<void(float)> progressCallback) {
if (progressCallback) progressCallback(0.0f);
auto result = LoadSceneFile(path);
if (!result.success) {
if (progressCallback) progressCallback(1.0f);
return false;
}
if (progressCallback) progressCallback(0.3f);
return ConstructScene(scene, result, std::move(progressCallback));
}
std::future<SceneSerializer::LoadResult> SceneSerializer::LoadSceneFileAsync(
const std::filesystem::path& path) {
return std::async(std::launch::async, [path]() {
return LoadSceneFile(path);
});
}