X Files

The X file format refers to files with the .x file name extension. X files were introduced with Microsoft® DirectX® 2.0. A binary version of this format was subsequently released with DirectX 3.0, which is also described in this documentation. DirectX 6.0 introduced interfaces and methods that enable reading from and writing to .x files.

X files provide a rich, template-driven format that enables the storage of meshes, textures, animations, and user-definable objects. Support for animation sets enables you to store predefined paths for playback in real time. Instancing and hierarchies are also supported. Instancing enables multiple references to an object, such as a mesh, while storing its data only once per file. Hierarchies are used to express relationships between data records.

The .x file format provides low-level data primitives on which applications define higher-level primitives through templates.

This section discusses the structure of .x files and how to use them in your applications.

Information is divided into the following topics.

• X File Interface Hierarchy
• X File Architecture
• Using X Files

For more information on the X File format, see X File Format Reference.