DirectX Foundation

The foundation layer is the internal part of Microsoft DirectX. It is a set of low-level APIs that are the basis for performance media on Windows-based computers. DirectX Foundation provides unmatched access to hardware acceleration and opens the door to true device independence, enabling developers to boost multimedia performance for all types of applications and platform configurations.

The 5 DirectX Foundation APIs are:

DirectDraw
A memory manager for graphics and video surfaces, Microsoft DirectDraw provides the foundation for high-performance multimedia on the Microsoft Windows platform. By bypassing the traditional layers associated with Windows-based graphics, DirectDraw allows direct access to display memory and hardware features, while maintaining compatibility with Windows-based applications.

DirectDraw works with a wide variety of display hardware, from simple monitors to advanced hardware implementations. Operating at the graphics surface level, DirectDraw provides the base for high-level graphics APIs. DirectDraw's graphics acceleration capability assesses the video hardware's capabilities, making use of special features whenever possible and emulating features not implemented in the hardware.

Direct3D Immediate Mode
Designed to enable world-class game and interactive 3-D graphics in Microsoft Windows, Direct3D Immediate Mode is an optimized 3-D draw engine for hardware acceleration and emulation.

Essentially, Microsoft® Direct3D® is a drawing interface for 3-D hardware. In the Immediate Mode, Direct3D allows developers to port games and other high-performance multimedia applications onto Microsoft® Windows®. Its features include switchable z-buffering, hardware independence, and support for the Intel MMX architecture. Direct3D Immediate mode also supports drawing primitives without the use of execute buffers.

DirectInput
Microsoft® DirectInput® provides a state-of-the art interface for a variety of input devices such as joysticks, headgear, multi-button mice, etc. as well as the new input-output devices known as force-feedback. DirectInput offers two key benefits over the current standard API functions: support for more types of devices and faster responsiveness. By working directly with device drivers, DirectInput bypasses the Microsoft® Windows® message system.

New features of DirectInput include support for new devices such as game pads, flight yokes, and virtual-reality headgear, as well as force-feedback devices that provide effects such as kickback when a trigger is fired, vibration, and resistance-making game experiences much more realistic and engaging.

DirectSound
The audio component of Microsoft® DirectX®, Microsoft® DirectSound® uses features such as low-latency mixing playback, accelerated hardware, and 3-D positioning to achieve professional-quality audio performance. With DirectSound, multiple audio signals can be mixed and played at the same time; sound card features are automatically engaged or emulated in the software if not supported by the existing hardware; and custom mixing engines can directly access the sound hardware. DirectSound also enables applications to change volume, frequency, and panning, and to simulate 3-D effects such as rolloff and Doppler shift.

New DirectSound features in DirectX 5 include audio capture (applications can now record as well as play back) and extended services using specific sound cards. Essentially a sound mixing engine, DirectSound places sets of sounds in secondary buffers, combines them and writes them into primary buffers. Only the available processing time limits the number of buffers that DirectSound can mix.

DirectSound 3D
The Microsoft® DirectX® audio playback services are designed to support the demanding requirements of games and interactive media applications for Microsoft Windows. Microsoft DirectSound3D allows you to transcend the limits of ordinary left-right balancing by making it possible to position sounds anywhere in three-dimensional space. And it can be accelerated in hardware or implemented in software when 3-D hardware is not available.

These system-level APIs offer extremely efficient access to advanced features of high-performance hardware including 3D-graphics acceleration chips, sound cards, and input devices. DirectX Foundation also frees developers from device-specific dependencies in hardware, eliminating problems such as driver and platform incompatibilities.

DirectX Links

Index

DirectX Media