About File Objects

A file object (or, more briefly, a file ) is a type of QuickDraw 3D object that you use to read and write data that conforms to the QuickDraw 3D Object Metafile (3DMF), a standard file format intended to facilitate the interchange of three-dimensional data among applications. You can use the 3DMF both as a 3D data storage format and as a 3D data interchange format. For example, when a user saves a 3D model created by your application, you can write the data to a file object. The data-writing methods of the file object and its associated storage object ensure that the data in the piece of storage associated with that storage object (for example, a file on disk or a block of memory) conforms to the 3DMF specification. All other applications capable of handling 3DMF files can thus open and read that data.

By using file objects, you can insulate your application from having to know the actual details of the QuickDraw 3D Object Metafile standard. You use file object routines to read and write data in a piece of storage that conforms to the 3DMF and, if necessary, to get information about that storage. In all likelihood, you'll need to know about the details of the 3DMF only if you cannot use file objects to access 3DMF data. For instance, you would need to know the structure of the 3DMF if you wanted to read and write 3DMF files using a 3D graphics system other than QuickDraw 3D.

See Quickdraw 3D 1.5 Metafile Reference for complete information about the structure of the QuickDraw 3D Object Metafile.

File I/O

File Types

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