Type Alias

CGDataProviderGetBytesCallback

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

Declaration

typedef size_t (*CGDataProviderGetBytesCallback)(void *info, void *buffer, size_t count);

Parameters

info

A generic pointer to private data shared among your callback functions. This is the same pointer you supplied to CGDataProviderCreate.

buffer

The Core Graphics buffer into which you copy the specified number of bytes.

count

The number of bytes to copy.

Return Value

The number of bytes copied. If no more data can be written to the buffer, you should return 0.

Discussion

When Core Graphics is ready to receive data from the provider data stream, your function is called. It should copy the specified number of bytes into buffer.

For information on how to associate your callback function with a data provider, see CGDataProviderCreate and CGDataProviderCallbacks.

See Also

Callbacks

CGDataProviderReleaseInfoCallback

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

CGDataProviderRewindCallback

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

CGDataProviderSkipBytesCallback

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

CGDataProviderSkipForwardCallback

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

CGDataProviderGetBytePointerCallback

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

CGDataProviderGetBytesAtOffsetCallback

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

CGDataProviderReleaseBytePointerCallback

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

CGDataProviderReleaseDataCallback

A callback function that releases data you supply to the function CGDataProviderCreateWithData.

CGDataProviderGetBytesAtPositionCallback

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