#include <CUTextureLoader.h>

Inheritance diagram for cugl::TextureLoader:

Public Member Functions
	TextureLoader ()

void	dispose () override

GLuint	getMinFilter () const

void	setMinFilter (GLuint minFilter)

GLuint	getMagFilter () const

void	setMagFilter (GLuint magFilter)

GLuint	getWrapS () const

void	setWrapS (GLuint wrap)

GLuint	getWrapT () const

void	setWrapT (GLuint wrap)

bool	hasMipMaps () const

void	setMipMaps (bool flag)

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

std::shared_ptr< Texture >	get (const std::string key) const

std::shared_ptr< Texture >	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 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

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)

bool	contains (const std::string key) const

bool	complete () const

float	progress () const

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

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

Protected Member Functions
void	parseAtlas (const std::shared_ptr< JsonValue > &json, const std::shared_ptr< Texture > &texture)

SDL_Surface *	preload (const std::string &source)

void	materialize (const std::string &key, SDL_Surface *surface, LoaderCallback callback)

void	materialize (const std::shared_ptr< JsonValue > &json, SDL_Surface *surface, 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

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

bool	purge (const std::string key) override

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

Protected Attributes
GLuint	_minfilter

GLuint	_magfilter

GLuint	_wraps

GLuint	_wrapt

bool	_mipmaps

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

std::unordered_set< std::string >	_queue

Protected Attributes inherited from cugl::BaseLoader
std::shared_ptr< ThreadPool >	_loader

AssetManager *	_manager

Detailed Description

This class is a specific implementation of Loader<Texture>

This asset loader allows us to allocate texture objects from the associated image files. A texture asset is identified by both its source file and its texture parameters. Hence you may wish to load a texture asset multiple times, though this is potentially wasteful regarding memory. However, changing the parameters for a texture asset will change the asset parameters in this loader as well.

Note that this implementation uses a two phase loading system. First, it loads as much of the asset as possible without using OpenGL. This allows us to load the texture in a separate thread. It then finishes off the remainder of asset loading using Application#schedule. This is a good template for asset loaders in general.

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.

Constructor & Destructor Documentation

◆ TextureLoader()

cugl::TextureLoader::TextureLoader ( )

Creates a new, uninitialized texture 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<TextureLoader> cugl::TextureLoader::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<TextureLoader> cugl::TextureLoader::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.

◆ dispose()

void cugl::TextureLoader::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.

◆ getMagFilter()

GLuint cugl::TextureLoader::getMagFilter ( ) const

inline

Returns the default mage filter for this loader.

The mag filter is the algorithm hint that OpenGL uses to make an image larger. The default is GL_LINEAR. Once this value is set, all future textures processed by this loader will have this mag filter.

Returns: the default mage filter for this loader

◆ getMinFilter()

GLuint cugl::TextureLoader::getMinFilter ( ) const

inline

Returns the default min filter for this loader.

The min filter is the algorithm hint that OpenGL uses to make an image smaller. The default is GL_NEAREST. Once this value is set, all future textures processed by this loader will have this min filter.

Returns: the default min filter for this loader.

◆ getWrapS()

GLuint cugl::TextureLoader::getWrapS ( ) const

inline

Returns the default horizontal wrap for this loader.

The default is GL_CLAMP_TO_EDGE. Once this value is set, all future textures processed by this loader will have this horizontal wrap.

Returns: the default horizontal wrap for this loader.

◆ getWrapT()

GLuint cugl::TextureLoader::getWrapT ( ) const

inline

Returns the default vertical wrap for this loader.

The default is GL_CLAMP_TO_EDGE. Once this value is set, all future textures processed by this loader will have this vertical wrap.

Returns: the default vertical wrap for this loader.

◆ hasMipMaps()

bool cugl::TextureLoader::hasMipMaps ( ) const

inline

Returns true if this loader generates mipmaps by default.

The default is false. If this value is set to true, all future textures processed by this loader will build mipmaps by default. Similarly, setting it to false suppresses mipmaps in all future textures.

Returns: true if this loader generates mipmaps by default.

◆ materialize() [1/2]

void cugl::TextureLoader::materialize	(	const std::shared_ptr< JsonValue > &	json,
		SDL_Surface *	surface,
		LoaderCallback	callback
	)

protected

Creates an OpenGL texture from the SDL_Surface accoring to the directory entry.

This method finishes the asset loading started in preload. This step is not safe to be done in a separate thread. Instead, it takes place in the main CUGL thread via Application#schedule.

This version of read provides support for JSON directories. A texture directory entry has the following values

 "file":         The path to the asset
 "mipmaps":      Whether to generate mipmaps (bool)
 "minfilter":    The name of the min filter ("nearest", "linear";
                 with mipmaps, "nearest-nearest", "linear-nearest",
                 "nearest-linear", or "linear-linear")
 "magfilter":    The name of the min filter ("nearest" or "linear")
 "wrapS":        The s-coord wrap rule ("clamp", "repeat", or "mirrored")
 "wrapT":        The t-coord wrap rule ("clamp", "repeat", or "mirrored")

The asset key is the key for the JSON directory entry

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

Parameters

json	The asset directory entry
surface	The SDL_Surface to convert
callback	An optional callback for asynchronous loading

◆ materialize() [2/2]

void cugl::TextureLoader::materialize	(	const std::string &	key,
		SDL_Surface *	surface,
		LoaderCallback	callback
	)

protected

Creates an OpenGL texture from the SDL_Surface, and assigns it the given key.

This method finishes the asset loading started in preload. This step is not safe to be done in a separate thread. Instead, it takes place in the main CUGL thread via Application#schedule.

The loaded texture will have default parameters for scaling and wrap. It will only have a mipmap if that is the default.

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

Parameters

key	The key to access the asset after loading
surface	The SDL_Surface to convert
callback	An optional callback for asynchronous loading

◆ parseAtlas()

void cugl::TextureLoader::parseAtlas	(	const std::shared_ptr< JsonValue > &	json,
		const std::shared_ptr< Texture > &	texture
	)

protected

Extracts any subtextures specified in an atlas

An atlas is specified as a list of named, four-element integer arrays. Each integer array specifies the left, top, right, and bottom pixels of the subtexture, respectively. Each subtexture will have the key of the main texture as the prefix (together with an underscore _) of its key.

Parameters

json	The asset directory entry
texture	The texture loaded for this asset

◆ preload()

SDL_Surface* cugl::TextureLoader::preload ( const std::string & source )

protected

Loads the portion of this asset that is safe to load outside the main thread.

It is not safe to create an OpenGL texture in a separate thread. However, it is safe to create an SDL_surface, which contains all of the data that we need to create an OpenGL texture. Hence this method does the maximum amount of work that can be done in asynchronous texture loading.

Parameters

source The pathname to the asset

Returns: the SDL_Surface with the texture information

◆ purge()

virtual bool cugl::TextureLoader::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::TextureLoader::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 will split the loading across the preload and materialize methods. This ensures that asynchronous loading is safe.

This version of read provides support for JSON directories. A texture directory entry has the following values

 "file":         The path to the asset
 "mipmaps":      Whether to generate mipmaps (bool)
 "minfilter":    The name of the min filter ("nearest", "linear";
                 with mipmaps, "nearest-nearest", "linear-nearest",
                 "nearest-linear", or "linear-linear")
 "magfilter":    The name of the min filter ("nearest" or "linear")
 "wrapS":        The s-coord wrap rule ("clamp", "repeat", or "mirrored")
 "wrapT":        The t-coord wrap rule ("clamp", "repeat", or "mirrored")

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::TextureLoader::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.

This method will split the loading across the preload and materialize methods. This ensures that asynchronous loading is safe.

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.

◆ setMagFilter()

void cugl::TextureLoader::setMagFilter ( GLuint magFilter )

inline

Sets the default mage filter for this loader.

The mag filter is the algorithm hint that OpenGL uses to make an image larger. The default is GL_LINEAR. Once this value is set, all future textures processed by this loader will have this mag filter.

Parameters

magFilter The default mage filter for this loader.

◆ setMinFilter()

void cugl::TextureLoader::setMinFilter ( GLuint minFilter )

inline

Sets the default min filter for this loader.

The min filter is the algorithm hint that OpenGL uses to make an image smaller. The default is GL_NEAREST. Once this value is set, all future textures processed by this loader will have this min filter.

Parameters

minFilter The default min filter for this loader.

◆ setMipMaps()

void cugl::TextureLoader::setMipMaps ( bool flag )

inline

Sets whether this loader generates mipmaps by default.

The default is false. If this value is set to true, all future textures processed by this loader will build mipmaps by default. Similarly, setting it to false suppresses mipmaps in all future textures.

Parameters

flag	Whether this loader generates mipmaps by default.

◆ setWrapS()

void cugl::TextureLoader::setWrapS ( GLuint wrap )

inline

Sets the default horizontal wrap for this loader.

The default is GL_CLAMP_TO_EDGE. Once this value is set, all future textures processed by this loader will have this horizontal wrap.

Parameters

wrap	The default horizontal wrap for this loader.

◆ setWrapT()

void cugl::TextureLoader::setWrapT ( GLuint wrap )

inline

Sets the default vertical wrap for this loader.

The default is GL_CLAMP_TO_EDGE. Once this value is set, all future textures processed by this loader will have this vertical wrap.

Parameters

wrap	The default vertical wrap for this loader.

Member Data Documentation

◆ _magfilter

GLuint cugl::TextureLoader::_magfilter

protected

The default mag filter

◆ _minfilter

GLuint cugl::TextureLoader::_minfilter

protected

The default min filter

◆ _mipmaps

bool cugl::TextureLoader::_mipmaps

protected

The default support for mipmaps

◆ _wraps

GLuint cugl::TextureLoader::_wraps

protected

The default s-coordinate wrap

◆ _wrapt

GLuint cugl::TextureLoader::_wrapt

protected

The default t-coordinate wrap

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

include/cugl/assets/CUTextureLoader.h

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ TextureLoader()

Member Function Documentation

◆ alloc() [1/2]

◆ alloc() [2/2]

◆ dispose()

◆ getMagFilter()

◆ getMinFilter()

◆ getWrapS()

◆ getWrapT()

◆ hasMipMaps()

◆ materialize() [1/2]

◆ materialize() [2/2]

◆ parseAtlas()

◆ preload()

◆ purge()

◆ read() [1/2]

◆ read() [2/2]

◆ setMagFilter()

◆ setMinFilter()

◆ setMipMaps()

◆ setWrapS()

◆ setWrapT()

Member Data Documentation

◆ _magfilter

◆ _minfilter

◆ _mipmaps

◆ _wraps

◆ _wrapt