#include <CUScene2Loader.h>

Inheritance diagram for cugl::Scene2Loader:

Public Member Functions
	Scene2Loader ()

virtual bool	init () override

virtual bool	init (const std::shared_ptr< ThreadPool > &threads) override

void	dispose () override

std::shared_ptr< scene2::SceneNode >	build (const std::string key, const std::shared_ptr< JsonValue > &json) const

Public Member Functions inherited from cugl::Loader< scene2::SceneNode >
	Loader ()

std::shared_ptr< scene2::SceneNode >	get (const std::string key) const

std::shared_ptr< scene2::SceneNode >	operator[] (const std::string key) const

size_t	loadCount () const override

size_t	waitCount () const override

void	unloadAll () override

Public Member Functions inherited from cugl::BaseLoader
	BaseLoader ()

	~BaseLoader ()

virtual void	dispose ()

virtual bool	init ()

virtual bool	init (const std::shared_ptr< ThreadPool > &threads)

std::shared_ptr< BaseLoader >	getHook ()

std::shared_ptr< ThreadPool >	getThreadPool () const

void	setThreadPool (const std::shared_ptr< ThreadPool > &threads)

void	setManager (AssetManager *manager)

const AssetManager *	getManager () const

void	setJsonKey (const std::string key)

const std::string	getJsonKey () const

void	setPriority (Uint32 priority)

const Uint32	getPriority () const

bool	load (const std::string key, const std::string source)

bool	load (const std::shared_ptr< JsonValue > &json)

void	loadAsync (const std::string key, const std::string source, LoaderCallback callback)

void	loadAsync (const std::shared_ptr< JsonValue > &json, LoaderCallback callback)

bool	unload (const std::string key)

bool	unload (const std::shared_ptr< JsonValue > &json)

virtual void	unloadAll ()

virtual std::vector< std::string >	keys ()

bool	contains (const std::string key) const

virtual size_t	loadCount () const

virtual size_t	waitCount () const

bool	complete () const

float	progress () const

Static Public Member Functions
static std::shared_ptr< Scene2Loader >	alloc ()

static std::shared_ptr< Scene2Loader >	alloc (const std::shared_ptr< ThreadPool > &threads)

Protected Types
enum class	Widget { NODE , IMAGE , SOLID , POLY , PATH , WIRE , ORDER , CANVAS , ANIMATE , NINE , LABEL , BUTTON , PROGRESS , SLIDER , SCROLL , TEXTFIELD , EXTERNAL_IMPORT , UNKNOWN }

enum class	Form { NONE , ANCHORED , FLOAT , GRID , UNKNOWN }

Protected Member Functions
void	materialize (const std::shared_ptr< scene2::SceneNode > &node, LoaderCallback callback)

virtual bool	read (const std::string key, const std::string source, LoaderCallback callback, bool async) override

virtual bool	read (const std::shared_ptr< JsonValue > &json, LoaderCallback callback, bool async) override

virtual bool	purge (const std::shared_ptr< JsonValue > &json) override

bool	attach (const std::string key, const std::shared_ptr< scene2::SceneNode > &node)

std::shared_ptr< JsonValue >	getWidgetJson (const std::shared_ptr< JsonValue > &json) const

Protected Member Functions inherited from cugl::Loader< scene2::SceneNode >
virtual std::vector< std::string >	keys () override

bool	purge (const std::string key) override

bool	verify (const std::string key) const override

virtual bool	read (const std::string key, const std::string source, LoaderCallback callback, bool async)

virtual bool	read (const std::shared_ptr< JsonValue > &json, LoaderCallback callback, bool async)

virtual bool	purge (const std::string key)

virtual bool	purge (const std::shared_ptr< JsonValue > &json)

virtual bool	verify (const std::string key) const

Protected Attributes
std::unordered_map< std::string, Widget >	_types

std::unordered_map< std::string, Form >	_forms

Protected Attributes inherited from cugl::Loader< scene2::SceneNode >
std::unordered_map< std::string, std::shared_ptr< scene2::SceneNode > >	_assets

std::unordered_set< std::string >	_queue

Protected Attributes inherited from cugl::BaseLoader
std::string	_jsonKey

Uint32	_priority

std::shared_ptr< ThreadPool >	_loader

AssetManager *	_manager

Detailed Description

This class is a specific implementation of Loader<Node>

This asset loader allows us to specify a scene graph subtree, which can be attached to a new or existing scene graph. This is particularly useful for desiging UI elements with a JSON directory structure rather than having to create them programmatically. While not exactly visual wireframing, this makes it easier for UX designers to layout user-interface elements, HUDS and the like.

As UI widgets typically require fonts and images to be loaded already, these should always be the last elements loaded in a loading phase.

As with all of our loaders, this loader is designed to be attached to an asset manager. Use the method getHook() to get the appropriate pointer for attaching the loader.

Member Enumeration Documentation

◆ Form

enum class cugl::Scene2Loader::Form

strongprotected

This is an enumeration for identifying layout managers.

Each time you add a new layout, it should be added to this list.

Enumerator
NONE	The default layout manager, using absolute position
ANCHORED	A layout manager using anchor points
FLOAT	A float layout manager
GRID	A grid layout manager
UNKNOWN	An unsupported form

◆ Widget

enum class cugl::Scene2Loader::Widget

strongprotected

This is an enumeration for identifying scene node types.

Each time you add a new UI widget, it should be added to this list.

Enumerator
NODE	The base Node type
IMAGE	An image (PolygoNode) type
SOLID	A rectangular PolygonNode type
POLY	A (complex) PolygonNode type
PATH	A PathNode type
WIRE	A WireNode type
ORDER	An ordered node (for non pre-traversals)
CANVAS	A canvas node for vector graphics
ANIMATE	An animation node type
NINE	A nine-patch type
LABEL	A text label (uneditable) type
BUTTON	A button type
PROGRESS	A progress bar type
SLIDER	A slider type
SCROLL	A scroll pane
TEXTFIELD	A single-line text field type
EXTERNAL_IMPORT	A Node implied by an imported file
UNKNOWN	An unsupported type

Constructor & Destructor Documentation

◆ Scene2Loader()

cugl::Scene2Loader::Scene2Loader ( )

inline

Creates a new, uninitialized scene loader

NEVER USE A CONSTRUCTOR WITH NEW. If you want to allocate a loader on the heap, use one of the static constructors instead.

Member Function Documentation

◆ alloc() [1/2]

static std::shared_ptr< Scene2Loader > cugl::Scene2Loader::alloc ( )

inlinestatic

Returns a newly allocated texture loader.

This method bootstraps the loader with any initial resources that it needs to load assets. In particular, the OpenGL context must be active. Attempts to load an asset before this method is called will fail.

This loader will have no associated threads. That means any asynchronous loading will fail until a thread is provided via setThreadPool.

Returns: a newly allocated texture loader.

◆ alloc() [2/2]

static std::shared_ptr< Scene2Loader > cugl::Scene2Loader::alloc ( const std::shared_ptr< ThreadPool > & threads )

inlinestatic

Returns a newly allocated texture loader.

This method bootstraps the loader with any initial resources that it needs to load assets. In particular, the OpenGL context must be active. Attempts to load an asset before this method is called will fail.

Parameters

threads The thread pool for asynchronous loading

Returns: a newly allocated texture loader.

◆ attach()

bool cugl::Scene2Loader::attach	(	const std::string	key,
		const std::shared_ptr< scene2::SceneNode > &	node
	)

protected

Attaches all generate nodes to the asset dictionary.

As the asset dictionary must be updated in the main thread, we do not update it until the entire node tree has been materialized. This method assumes that each Node is named with its asset look-up key.

Parameters

key	The key to access the asset after loading
node	The scene asset

Returns: true if the node was successfully attached

◆ build()

std::shared_ptr< scene2::SceneNode > cugl::Scene2Loader::build	(	const std::string	key,
		const std::shared_ptr< JsonValue > &	json
	)		const

Recursively builds the scene from the given JSON tree.

This method allows us to maximize the asynchronous creation of scenes. The key is assigned as the name of the root Node of the scene.

The JSON tree should be a tree of widget objects, where each widget object has the following attribute values:

 "type":     The node type (a Node or any subclass)
 "data":     Data (images, labels) that define the widget.  This
             JSON object has a node-specific format.
 "format":   The layout manager to use for this Node. This layout
             manager will apply to all the children (see below).
             This JSON object has a layout-specific format.
 "layout":   Node placement using a the layout manager of the parent.
             This is applied after parsing "data' and will override
             any settings there. This JSON object has a
             layout-specific format.
 "children": Any child Nodes of this one. This JSON object has a
             named attribute for each child.

With the exception of "type", all of these attributes are JSON objects.

Parameters

key	The key to access the scene after loading
json	The JSON object defining the scene

Returns: the SDL_Surface with the texture information

◆ dispose()

void cugl::Scene2Loader::dispose ( )

inlineoverridevirtual

Disposes all resources and assets of this loader

Any assets loaded by this object will be immediately released by the loader. However, a texture may still be available if it is referenced by another smart pointer. OpenGL will only release a texture asset once all smart pointer attached to the asset are null.

Once the loader is disposed, any attempts to load a new asset will fail. You must reinitialize the loader to begin loading assets again.

Reimplemented from cugl::BaseLoader.

◆ getWidgetJson()

std::shared_ptr< JsonValue > cugl::Scene2Loader::getWidgetJson ( const std::shared_ptr< JsonValue > & json ) const

protected

Translates the JSON of a widget to the JSON of the node that it encodes.

If this scene is built before the JSON of any used widgets have been loaded, this will fail.

Parameters

json	The JSON object specifying the widget's file and the values for its exposed variables

Returns: the JSON loaded from the widget file with all variables set based on the values presented in json.

◆ init() [1/2]

virtual bool cugl::Scene2Loader::init ( )

inlineoverridevirtual

Initializes a new asset loader.

This method bootstraps the loader with any initial resources that it needs to load assets. Attempts to load an asset before this method is called will fail.

This loader will have no associated threads. That means any asynchronous loading will fail until a thread is provided via setThreadPool.

This method is abstract and should be overridden in the specific implementation for each asset.

Returns: true if the asset loader was initialized successfully

Reimplemented from cugl::BaseLoader.

◆ init() [2/2]

virtual bool cugl::Scene2Loader::init ( const std::shared_ptr< ThreadPool > & threads )

overridevirtual

Initializes a new asset loader.

This method bootstraps the loader with any initial resources that it needs to load assets. Attempts to load an asset before this method is called will fail.

This method is abstract and should be overridden in the specific implementation for each asset.

Parameters

threads The thread pool for asynchronous loading support

Returns: true if the asset loader was initialized successfully

Reimplemented from cugl::BaseLoader.

◆ materialize()

void cugl::Scene2Loader::materialize	(	const std::shared_ptr< scene2::SceneNode > &	node,
		LoaderCallback	callback
	)

protected

Records the given Node with this loader, so that it may be unloaded later.

This method finishes the asset loading started in load. This step is not safe to be done in a separate thread, as it accesses the main asset table. Therefore, it takes place in the main CUGL thread via Application#schedule. The scene is stored using the name of the root Node as a key.

This method supports an optional callback function which reports whether the asset was successfully materialized.

Parameters

node	The scene asset
callback	An optional callback for asynchronous loading

◆ purge()

virtual bool cugl::Scene2Loader::purge ( const std::shared_ptr< JsonValue > & json )

overrideprotectedvirtual

Unloads the asset for the given directory entry

An asset may still be available if it is referenced by a smart pointer. See the description of the specific implementation for how assets are released.

This method is abstract and should be overridden in child classes. You will notice that this method is essentially identical to unload. We separated the methods because overloading and virtual methods do not place nice.

Parameters

json	The directory entry for the asset

Returns: true if the asset was successfully unloaded

Reimplemented from cugl::BaseLoader.

◆ read() [1/2]

virtual bool cugl::Scene2Loader::read	(	const std::shared_ptr< JsonValue > &	json,
		LoaderCallback	callback,
		bool	async
	)

overrideprotectedvirtual

Internal method to support asset loading.

This method supports either synchronous or asynchronous loading, as specified by the given parameter. If the loading is asynchronous, the user may specify an optional callback function.

This method is like the traditional read method except that it assumes the JSON data has already been parsed.

Parameters

json	The directory entry for the asset
callback	An optional callback for asynchronous loading
async	Whether the asset was loaded asynchronously

Returns: true if the asset was successfully loaded

Reimplemented from cugl::BaseLoader.

◆ read() [2/2]

virtual bool cugl::Scene2Loader::read	(	const std::string	key,
		const std::string	source,
		LoaderCallback	callback,
		bool	async
	)

overrideprotectedvirtual

Internal method to support asset loading.

This method supports either synchronous or asynchronous loading, as specified by the given parameter. If the loading is asynchronous, the user may specify an optional callback function.

The sources must be a JSON file. It will parse the JSON tree of this file, assigning the given key to the root node. The JSON tree should be a tree of widget objects, where each widget object has the following attribute values:

 "type":     The node type (a Node or any subclass)
 "data":     Data (images, labels) that define the widget.  This
             JSON object has a node-specific format.
 "format":   The layout manager to use for this Node. This layout
             manager will apply to all the children (see below).
             This JSON object has a layout-specific format.
 "layout":   Node placement using a the layout manager of the parent.
             This is applied after parsing "data' and will override
             any settings there. This JSON object has a
             layout-specific format.
 "children": Any child Nodes of this one. This JSON object has a
             named attribute for each child.

With the exception of "type", all of these attributes are JSON objects.

Parameters

key	The key to access the asset after loading
source	The pathname to the asset
callback	An optional callback for asynchronous loading
async	Whether the asset was loaded asynchronously

Returns: true if the asset was successfully loaded

Reimplemented from cugl::BaseLoader.

Member Data Documentation

◆ _forms

std::unordered_map<std::string,Form> cugl::Scene2Loader::_forms

protected

The type map for managing layout

◆ _types

std::unordered_map<std::string,Widget> cugl::Scene2Loader::_types

protected

The type map for managing constructors

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

cugl/include/cugl/assets/CUScene2Loader.h

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ Form

◆ Widget

Constructor & Destructor Documentation

◆ Scene2Loader()

Member Function Documentation

◆ alloc() [1/2]

◆ alloc() [2/2]

◆ attach()

◆ build()

◆ dispose()

◆ getWidgetJson()

◆ init() [1/2]

◆ init() [2/2]

◆ materialize()

◆ purge()

◆ read() [1/2]

◆ read() [2/2]

Member Data Documentation

◆ _forms

◆ _types