CTextureCacheJob Class Reference

Job class for caching textures. More...

#include <TextureCacheJob.h>

Inheritance diagram for CTextureCacheJob:

Public Member Functions
	CTextureCacheJob (const std::string &url, const CTextureDetails &oldDetails={}, const std::string &knownHash="")
	~CTextureCacheJob () override
const char *	GetType () const override
	Function that returns the type of job.
bool	Equals (const CJob *job) const override
	Function that compares this job instance with the given job instance.
bool	DoWork () override
	Main workhorse function of CJob instances.
bool	CacheTexture (std::unique_ptr< CTexture > *texture=nullptr)
	retrieve a hash for the given image Combines the size, ctime and mtime of the image file into a "unique" hash
Public Member Functions inherited from CJob
	CJob ()=default
virtual	~CJob ()=default
	Destructor for job objects.
void	SetProgressCallback (CJobManager *callback)
	Function to set a callback for jobs to report progress.
virtual bool	ShouldCancel (unsigned int progress, unsigned int total) const
	Function for longer jobs to report progress and check whether they have been cancelled.
size_t	GetPendingCallbackCount () const
	Get the number of callbacks pending for this job during completion.

Static Public Member Functions
static bool	ResizeTexture (const std::string &url, unsigned int height, unsigned int width, CPictureScalingAlgorithm::Algorithm scalingAlgorithm, uint8_t *&result, size_t &result_size)
static std::string	GetImageHash (const CFileItem &listedFile)
	Retrieve a hash for a file already returned by a directory listing.
static bool	MayBeAnImage (const std::string &mimeType)
	Whether a mime type leaves an image possible.

Public Attributes
std::string	m_url
CTextureDetails	m_oldDetails
CTextureDetails	m_details
bool	m_holdsProcessingClaim {false}
	Whether this job is the one that reserved m_url in the texture cache. Only the reserver may release it.

Static Public Attributes
static constexpr const char *	JOB_TYPE_CACHE_IMAGE = "cacheimage"

Additional Inherited Members
Public Types inherited from CJob
enum	PRIORITY {   PRIORITY_LOW_PAUSABLE = 0 , PRIORITY_LOW , PRIORITY_NORMAL , PRIORITY_HIGH ,   PRIORITY_DEDICATED }
	Priority levels for jobs, specified by clients when adding jobs to the CJobManager. More...

Detailed Description

Job class for caching textures.

Handles loading and caching of textures.

Constructor & Destructor Documentation

CTextureCacheJob()

CTextureCacheJob::CTextureCacheJob	(	const std::string &	url,
		const CTextureDetails &	oldDetails = {},
		const std::string &	knownHash = "" )

Parameters

url	location of the image
oldDetails	what the image is already cached as, if anything. Its hash is only set once the image is due its periodic check, and an unchanged image is then revalidated rather than cached all over again.
knownHash	hash of the source file, if the caller already knows it (see GetImageHash())

~CTextureCacheJob()

CTextureCacheJob::~CTextureCacheJob ( )

overridedefault

Member Function Documentation

CacheTexture()

bool CTextureCacheJob::CacheTexture

(

std::unique_ptr< CTexture > *

texture = nullptr

)

retrieve a hash for the given image Combines the size, ctime and mtime of the image file into a "unique" hash

Parameters

url	location of the image

Returns

a hash string for this image

DoWork()

bool CTextureCacheJob::DoWork ( )

overridevirtual

Main workhorse function of CJob instances.

All CJob subclasses must implement this function, performing all processing. Once this function is complete, the OnJobComplete() callback is called, and the job is then destroyed.

See also

CJobManager, IJobCallback::OnJobComplete()

Implements CJob.

Equals()

bool CTextureCacheJob::Equals ( const CJob * job ) const

overridevirtual

Function that compares this job instance with the given job instance.

CJob subclasses may optionally implement this to provide customized comparison functionality. This is useful for the CJobManager::AddJob() routine, which preempts similar jobs with the new job.

Parameters

job	the job to compared with this CJob instance.

Returns

if true, the two jobs are equal.

See also

CJobManager::AddJob()

Reimplemented from CJob.

GetImageHash()

std::string CTextureCacheJob::GetImageHash ( const CFileItem & listedFile )

static

Retrieve a hash for a file already returned by a directory listing.

Parameters

listedFile

the file, as listed by CDirectory::GetDirectory() without DIR_FLAG_NO_FILE_INFO

Returns

a hash string for this file, or empty if the listing didn't provide the information - not every VFS layer does, and the caller should then let the file be stat'ed as usual

GetType()

const char * CTextureCacheJob::GetType ( ) const

inlineoverridevirtual

Function that returns the type of job.

CJob subclasses may optionally implement this function to specify the type of job. This is useful for the CJobManager::AddJob() routine, which preempts similar jobs with the new job.

Returns

a unique character string describing the job.

See also

CJobManager

Reimplemented from CJob.

MayBeAnImage()

bool CTextureCacheJob::MayBeAnImage ( const std::string & mimeType )

static

Whether a mime type leaves an image possible.

Parameters

mimeType

the type to consider, empty if nothing has said what it is

Returns

true for an image type, and for the type a source gives when it doesn't know

ResizeTexture()

bool CTextureCacheJob::ResizeTexture ( const std::string & url, unsigned int height, unsigned int width, CPictureScalingAlgorithm::Algorithm scalingAlgorithm, uint8_t *& result, size_t & result_size )

static

Member Data Documentation

JOB_TYPE_CACHE_IMAGE

const char* CTextureCacheJob::JOB_TYPE_CACHE_IMAGE = "cacheimage"

staticconstexpr

m_details

CTextureDetails CTextureCacheJob::m_details

m_holdsProcessingClaim

bool CTextureCacheJob::m_holdsProcessingClaim {false}

Whether this job is the one that reserved m_url in the texture cache. Only the reserver may release it.

See also

CTextureCache::StartCacheImage, CTextureCache::OnCachingComplete

m_oldDetails

CTextureDetails CTextureCacheJob::m_oldDetails

m_url

std::string CTextureCacheJob::m_url

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

• TextureCacheJob.h
• TextureCacheJob.cpp