Scene Class Reference

Represents a scene containing objects and components. More...

#include <Scene.h>

Public Types
using	OnObjectsAboutToBeDestroyedFn = std::function<void(const std::vector<DekiObject*>&)>

Public Member Functions
	Scene ()
	~Scene ()
DekiObject *	Instantiate (Scene *targetScene)
	Instantiate this scene into another scene.
DekiObject *	Instantiate (Scene *targetScene, float x, float y)
	Instantiate this scene with a specific position.
void	AddObject (DekiObject *obj)
void	RemoveObject (DekiObject *obj)
const std::vector< DekiObject * > &	GetObjects () const
const std::vector< DekiBehaviour * > &	GetBehaviours ()
void	InvalidateBehavioursCache ()
DekiObject *	CreateDekiObject (const std::string &name="DekiObject")
void	DestroyDekiObject (DekiObject *dekiObject)
DekiObject *	FindDekiObject (const std::string &name)
DekiObject *	FindDekiObject (uint32_t id)
bool	LoadData (const uint8_t *data, size_t size)
void	InsertObjectAt (DekiObject *obj, size_t index)
int	GetObjectIndex (DekiObject *obj) const
bool	SaveToFile (const std::string &filePath)
bool	LoadFromFile (const std::string &filePath)
std::string	SaveToJsonString ()
bool	LoadFromJsonString (const std::string &jsonStr)
DekiObject *	DuplicateObject (const DekiObject *source)
bool	ExpandInstance (DekiObject *instanceObj)
void	CollapseInstance (DekiObject *instanceObj)
void	ApplyOverrides (DekiObject *instanceObj, const nlohmann::json &overrides)
void	CollectOverrides (const DekiObject *instanceRoot, const DekiObject *obj, nlohmann::json &overrides) const
void	SetOnObjectsAboutToBeDestroyed (OnObjectsAboutToBeDestroyedFn fn)
	Out of line: the callback is stored in a side table in Scene.cpp, not in a member, so that sizeof(Scene) does not depend on DEKI_EDITOR.
const std::string &	GetName () const
void	SetName (const std::string &sceneName)
bool	IsLoaded () const

Static Public Member Functions
static Scene *	Load (const char *path, bool cache=false)
	Load a scene by asset path through AssetManager.
static Scene *	LoadInternal (const char *path)
	Load a scene directly from the filesystem (binary MessagePack).
static Scene *	LoadFromMemory (const uint8_t *data, size_t size)
	Load a scene from memory buffer.
static std::vector< std::pair< std::string, std::string > >	CollectUnknownProperties ()
	Property keys found in a scene file that no component's current metadata recognises, as {component type name, key}.
static void	ClearUnknownProperties ()
	Forget everything collected so far, so a check can scope itself to the scenes it is about to load.
static std::vector< std::pair< std::string, std::string > >	CollectLegacyProperties ()
	Property keys read through a DEKI_RENAMED_FROM alias since the last clear, as {component type name, old key}: the file still carries the name from before a rename.
static nlohmann::json	ComponentPropertiesToJson (const DekiComponent *comp, const DekiComponentMeta &meta)
	Every reflected property of comp — its base class's first, then its own — as the JSON a scene file holds for it, keyed by reflected name.
static nlohmann::json	ComponentDefaultsToJson (const DekiComponentMeta &meta)
	ComponentPropertiesToJson for a default-constructed instance of meta.

Static Public Attributes
static constexpr const char *	AssetTypeName = "Scene"
	Asset type name for AssetManager::Load<T>() lookup.
static std::function< std::string(const std::string &guid)>	s_GuidToPathResolver

Detailed Description

Represents a scene containing objects and components.

A Scene is the fundamental content unit in Deki Engine. It can contain objects with components and can be:

• Loaded as the active/running scene
• Instanced inside another scene (what other engines call a prefab)
• Distributed and loaded at runtime

This unified concept eliminates the scene/prefab distinction other engines draw - here everything is a scene.

Member Typedef Documentation

OnObjectsAboutToBeDestroyedFn

using Scene::OnObjectsAboutToBeDestroyedFn = std::function<void(const std::vector<DekiObject*>&)>

Constructor & Destructor Documentation

Scene()

Scene::Scene

(

)

~Scene()

Scene::~Scene

(

)

Member Function Documentation

Load()

Scene * Scene::Load ( const char * path, bool cache = false )

static

Load a scene by asset path through AssetManager.

Always returns a fresh Scene instance with the original data.

Parameters

path	Asset-relative path without extension (e.g., "scenes/settings/settings")
cache	If true, pins the raw file bytes in RAM so subsequent loads skip disk I/O. If false (default), reads from disk every time. Either way, a fresh instance is returned — cached bytes are never mutated.

Returns

Loaded scene or nullptr on failure

LoadInternal()

Scene * Scene::LoadInternal ( const char * path )

static

Load a scene directly from the filesystem (binary MessagePack).

Parameters

path	Resolved filesystem path to the compiled .scene binary

Returns

Loaded scene or nullptr on failure

Note

Used internally by AssetManager and SceneSystem. Prefer Load() for user code.

LoadFromMemory()

Scene * Scene::LoadFromMemory ( const uint8_t * data, size_t size )

static

Load a scene from memory buffer.

Parameters

data	Pointer to scene data
size	Size of the data

Returns

Loaded scene or nullptr on failure

Instantiate() [1/2]

DekiObject * Scene::Instantiate

(

Scene *

targetScene

)

Instantiate this scene into another scene.

Parameters

targetScene

The scene to add the instanced objects to

Returns

The root DekiObject of the instanced scene, or nullptr on failure

Instantiate() [2/2]

DekiObject * Scene::Instantiate	(	Scene *	targetScene,
		float	x,
		float	y )

Instantiate this scene with a specific position.

Parameters

targetScene	The scene to add the instanced objects to
x	X position for the root object
y	Y position for the root object

Returns

The root DekiObject of the instanced scene, or nullptr on failure

AddObject()

void Scene::AddObject

(

DekiObject *

obj

)

RemoveObject()

void Scene::RemoveObject

(

DekiObject *

obj

)

GetObjects()

const std::vector< DekiObject * > & Scene::GetObjects ( ) const

inline

GetBehaviours()

const std::vector< DekiBehaviour * > & Scene::GetBehaviours

(

)

InvalidateBehavioursCache()

void Scene::InvalidateBehavioursCache ( )

inline

CreateDekiObject()

DekiObject * Scene::CreateDekiObject

(

const std::string &

name = "DekiObject"

)

DestroyDekiObject()

void Scene::DestroyDekiObject

(

DekiObject *

dekiObject

)

FindDekiObject() [1/2]

DekiObject * Scene::FindDekiObject

(

const std::string &

name

)

FindDekiObject() [2/2]

DekiObject * Scene::FindDekiObject

(

uint32_t

id

)

LoadData()

bool Scene::LoadData	(	const uint8_t *	data,
		size_t	size )

InsertObjectAt()

void Scene::InsertObjectAt	(	DekiObject *	obj,
		size_t	index )

GetObjectIndex()

int Scene::GetObjectIndex

(

DekiObject *

obj

)

const

SaveToFile()

bool Scene::SaveToFile

(

const std::string &

filePath

)

LoadFromFile()

bool Scene::LoadFromFile

(

const std::string &

filePath

)

SaveToJsonString()

std::string Scene::SaveToJsonString

(

)

LoadFromJsonString()

bool Scene::LoadFromJsonString

(

const std::string &

jsonStr

)

DuplicateObject()

DekiObject * Scene::DuplicateObject

(

const DekiObject *

source

)

ExpandInstance()

bool Scene::ExpandInstance

(

DekiObject *

instanceObj

)

CollapseInstance()

void Scene::CollapseInstance

(

DekiObject *

instanceObj

)

ApplyOverrides()

void Scene::ApplyOverrides	(	DekiObject *	instanceObj,
		const nlohmann::json &	overrides )

CollectOverrides()

void Scene::CollectOverrides	(	const DekiObject *	instanceRoot,
		const DekiObject *	obj,
		nlohmann::json &	overrides ) const

CollectUnknownProperties()

std::vector< std::pair< std::string, std::string > > Scene::CollectUnknownProperties ( )

static

Property keys found in a scene file that no component's current metadata recognises, as {component type name, key}.

Reflected member names ARE the scene-file format: reflection_codegen emits each C++ identifier as a DekiHashString key, with no opt-in gate. So renaming a reflected member silently changes the on-disk key, the parser's switch falls through, and the property reverts to its default — no error, no log line. The value itself survives (unknown keys are re-emitted on save), but the behaviour is gone.

This is the detector for that. Load every scene in a project and assert this comes back empty; a missed rename names itself. Populated on load, so it reflects the scenes loaded so far in this session.

ClearUnknownProperties()

void Scene::ClearUnknownProperties ( )

static

Forget everything collected so far, so a check can scope itself to the scenes it is about to load.

Clears the legacy list too.

CollectLegacyProperties()

std::vector< std::pair< std::string, std::string > > Scene::CollectLegacyProperties ( )

static

Property keys read through a DEKI_RENAMED_FROM alias since the last clear, as {component type name, old key}: the file still carries the name from before a rename.

A save writes the current name, so this is a warning ("re-save to migrate"), not an error.

ComponentPropertiesToJson()

nlohmann::json Scene::ComponentPropertiesToJson ( const DekiComponent * comp, const DekiComponentMeta & meta )

static

Every reflected property of comp — its base class's first, then its own — as the JSON a scene file holds for it, keyed by reflected name.

The same writer SaveToFile uses, so a value prints exactly as it would be saved. The docs build reads default values through this.

ComponentDefaultsToJson()

nlohmann::json Scene::ComponentDefaultsToJson ( const DekiComponentMeta & meta )

static

ComponentPropertiesToJson for a default-constructed instance of meta.

Null when the type is abstract or has no factory.

SetOnObjectsAboutToBeDestroyed()

void Scene::SetOnObjectsAboutToBeDestroyed

(

OnObjectsAboutToBeDestroyedFn

fn

)

Out of line: the callback is stored in a side table in Scene.cpp, not in a member, so that sizeof(Scene) does not depend on DEKI_EDITOR.

std::function is 32 bytes here — too much to carry unconditionally on an embedded target that can never invoke it.

GetName()

const std::string & Scene::GetName ( ) const

inline

SetName()

void Scene::SetName ( const std::string & sceneName )

inline

IsLoaded()

bool Scene::IsLoaded ( ) const

inline

Member Data Documentation

AssetTypeName

const char* Scene::AssetTypeName = "Scene"

staticconstexpr

Asset type name for AssetManager::Load<T>() lookup.

s_GuidToPathResolver

std::function<std::string(const std::string& guid)> Scene::s_GuidToPathResolver

static

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The documentation for this class was generated from the following file:

• deki-engine/src/Scene.h