UrlFileCacheInterface Class Reference | C4D R23.110 C++ SDK - 中文文档编制,帮助,手册,教程

UrlFileCacheInterface Class Reference

#include <urlfile_cache.h>

详细描述

UrlFileCacheInterface offers helper functions to allow to access to files with unsupported URLSCHEMEs. E.g. preset:// wont work with openexr because this lib needs a valid utf8 character path and InputStreams cannot be used to virtualize the read. In that case you would write:

maxon::Url url = MaxonConvert (name, MAXONCONVERTMODE::READ ); maxon::UrlFileCacheEntry fileCacheEntry;

if (! maxon::UrlFileCacheInterface::IsAccessible (url)) { fileCacheEntry = maxon::UrlFileCacheInterface::FindOrCreateUrl (url) iferr_return ; url = fileCacheEntry.GetCacheUrl(); } ifnoerr ( maxon::BaseArray<Char> buffer = url.GetSystemPath().GetCString(maxon::StringEncodings::Utf8())) return exr_load(buffer.GetFirst(), &wbm); else return IMAGERESULT ::MISC_ERROR;

静态公共成员函数
static MAXON_METHOD Bool	IsAccessible (const maxon::Url &url)
static MAXON_METHOD Result < UrlFileCacheEntry >	FindOrCreateUrl (const Url &sourceUrl, const TimeValue &maxCacheTime= Seconds (1.0), URLFILECACHEFLAGS flags= URLFILECACHEFLAGS::NONE )
static MAXON_METHOD Result < void >	FlushCache (const Url &url)

私有成员函数
	MAXON_INTERFACE_NONVIRTUAL ( UrlFileCacheInterface , MAXON_REFERENCE_NONE , "net.maxon.interface.urlfilecache")

成员函数文档编制

◆ MAXON_INTERFACE_NONVIRTUAL()

MAXON_INTERFACE_NONVIRTUAL	(	UrlFileCacheInterface	,
		MAXON_REFERENCE_NONE	,
		"net.maxon.interface.urlfilecache"
	)

private

◆ IsAccessible()

static MAXON_METHOD Bool IsAccessible

(

const maxon::Url &

url

)

static

Check if the url scheme is directly accessible via fopen().

参数

[in]

url

Url to check.

返回: true if the url can accessed directly. false if the url needs a cached copy. in that case use UrlFileCacheInterface::FindOrCreateUrl() to create or find the cache file.

◆ FindOrCreateUrl()

static MAXON_METHOD Result <UrlFileCacheEntry> FindOrCreateUrl	(	const Url &	sourceUrl ,
		const TimeValue &	maxCacheTime = `Seconds(1.0)` ,
		URLFILECACHEFLAGS	flags = `URLFILECACHEFLAGS::NONE`
	)

static

Finds or creates a new UrlFileCacheEntry for the given source Url .

参数

[in]	sourceUrl	Url to be cached.
[in]	maxCacheTime	Time to wait until to delete the cache file after it's not needed anymore.
[in]	flags	See URLFILECACHEFLAGS.

返回: A UrlFileCacheEntry which ensures the existence of the cache file as long as any reference to this handle exists.

◆ FlushCache()

static MAXON_METHOD Result <void> FlushCache

(

const Url &

url

)

static

Flushes the url from the cache. Existing UrlFileCacheEntries keep alive until the last handle vanishes. Calling the FindOrCreateUrl will create a new cache file for this url.

maxon::UrlFileCacheInterface::FindOrCreateUrl

static MAXON_METHOD Result< UrlFileCacheEntry > FindOrCreateUrl(const Url &sourceUrl, const TimeValue &maxCacheTime=Seconds(1.0), URLFILECACHEFLAGS flags=URLFILECACHEFLAGS::NONE)

ifnoerr

#define ifnoerr(...)

The opposite of iferr.

定义： errorbase.h:385

iferr_return

#define iferr_return

定义： resultbase.h:1434

maxon::BaseArray< Char >

maxon::Url

定义： url.h:819

MaxonConvert

maxon::Url MaxonConvert(const Filename &fn, MAXONCONVERTMODE convertMode)