Inside Macintosh: 3D Graphics Programming With QuickDraw 3D /

Chapter 16 - Storage Objects / Storage Objects Reference

Storage Objects Routines / Creating and Accessing Memory Storage Objects

Q3MemoryStorage_SetBuffer

You can use the Q3MemoryStorage_SetBuffer function to set the data of a memory storage object.

TQ3Status Q3MemoryStorage_SetBuffer (
TQ3StorageObject storage, 
unsigned char *buffer, 
unsigned long validSize, 
unsigned long bufferSize);

storage

A memory storage object.

buffer

A pointer to a block of memory to be associated with the specified storage object, or NULL.

validSize

The size, in bytes, of the valid metafile data contained in the specified buffer. If the value of buffer is NULL, this parameter specifies the initial size and also the grow size of the buffer that QuickDraw 3D allocates internally.

bufferSize

The size, in bytes, of the specified buffer.

DESCRIPTION

The Q3MemoryStorage_SetBuffer function sets the buffer location, size, and valid size of the memory storage object specified by the storage parameter to the values specified in the buffer, bufferSize, and validSize parameters.

If you pass the value NULL in the buffer parameter, QuickDraw 3D allocates a buffer of validSize bytes, increases the buffer by that size whenever necessary, and later disposes of the buffer when the associated storage object is closed or disposed of. If buffer is set to NULL and validSize is set to 0, QuickDraw 3D uses a default initial buffer and grow size.

SPECIAL CONSIDERATIONS

You must not use Q3MemoryStorage_SetBuffer with an open memory storage object.