Initializer

init(directInfo:size:callbacks:)

Creates a direct-access data provider.

Declaration

init?(directInfo info: UnsafeMutableRawPointer?, size: off_t, callbacks: UnsafePointer<CGDataProviderDirectCallbacks>)

Parameters

info

A pointer to data of any type or NULL. When Core Graphics calls the functions specified in the callbacks parameter, it sends each of the functions this pointer.

size

The number of bytes of data to provide.

callbacks

A pointer to a CGDataProviderDirectCallbacks structure that specifies the callback functions you implement to handle the data provider’s basic memory management.

Return Value

A new data provider. You are responsible for releasing this object using CGDataProviderRelease.

Discussion

You use this function to create a direct-access data provider that uses callback functions to read data from your program in a single block.

See Also

Creating Direct-Access Data Providers

init?(data: CFData)

Creates a data provider that reads from a CFData object.

init?(url: CFURL)

Creates a direct-access data provider that uses a URL to supply data.

init?(filename: UnsafePointer<Int8>)

Creates a direct-access data provider that uses a file to supply data.

struct CGDataProviderDirectCallbacks

Defines pointers to client-defined callback functions that manage the sending of data for a direct-access data provider.

typealias CGDataProviderGetBytePointerCallback

A callback function that returns a generic pointer to the provider data.

typealias CGDataProviderGetBytesAtPositionCallback

A callback function that copies data from the provider into a Core Graphics buffer.

typealias CGDataProviderReleaseBytePointerCallback

A callback function that releases the pointer Core Graphics obtained by calling CGDataProviderGetBytePointerCallback.

typealias CGDataProviderReleaseInfoCallback

A callback function that releases any private data or resources associated with the data provider.

typealias CGDataProviderReleaseDataCallback

A callback function that releases data you supply to the function init(dataInfo:data:size:releaseData:).