Structure

CGDataProviderSequentialCallbacks

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

Declaration

typedef struct CGDataProviderSequentialCallbacks {
    ...
} CGDataProviderSequentialCallbacks;

Overview

The functions specified by the CGDataProviderSequentialCallbacks structure are responsible for sequentially copying data to a memory buffer for Core Graphics to use. The functions are also responsible for handling the data provider’s basic memory management. You supply a CGDataProviderCallbacks structure to the function CGDataProviderCreateSequential to create a sequential-access data provider.

Topics

Instance Properties

getBytes

A pointer to a function that copies data from the provider. For more information, see CGDataProviderGetBytesCallback.

releaseInfo

A pointer to a function that handles clean-up for the data provider, or NULL. For more information, see CGDataProviderReleaseInfoCallback.

rewind

A pointer to a function Core Graphics calls to return the provider to the beginning of the data stream. For more information, see CGDataProviderRewindCallback.

skipForward

A pointer to a function that Core Graphics calls to advance the stream of data supplied by the provider.

version

The version of this structure. It should be set to 0.

See Also

Creating Sequential-Access Data Providers

CGDataProviderCreateSequential

Creates a sequential-access data provider.

CGDataProviderRewindCallback

A callback function that moves the current position in the data stream back to the beginning.

CGDataProviderGetBytesCallback

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

CGDataProviderSkipForwardCallback

A callback function that advances the current position in the data stream supplied by the provider.

CGDataProviderReleaseInfoCallback

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