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Related to DirectX: Directx 10, DirectX 11


(programming, hardware)
A Microsoft programming interface standard, first included with Windows 95. DirectX gives (games) programmers a standard way to gain direct access to enhanced hardware features under Windows 95 instead of going via the Windows 95 GDI. Some DirectX code runs faster than the equivalent under MS DOS.

DirectX promises performance improvements for graphics, sound, video, 3D, and network capabilites of games, but only where both hardware and software support DirectX.

DirectX 2 introduced the Direct3D interface. Version 5 was current at 1998-02-01. Version 8.1 is included in Windows XP.

Latest version: 8.1 (as of 2001-12-31).


A set of Windows interfaces from Microsoft for programming graphics and sound. Windows developers program to the DirectX APIs, and the manufacturers of sound and graphics cards write DirectX drivers to be included with their hardware. DirectX provides a high-level interface for accessing low-level functions "directly." It accesses the hardware abstraction layer in Windows (see HAL).

The first DirectX API was introduced in late 1995 to encourage game developers to move their software to Windows. Before DirectX, games for the PC were written in DOS in order to redraw the screen fast enough for real-time animation. To obtain the speed, gaming companies had to write drivers for a variety of graphics cards, which was a development headache.

A Single Graphics Interface for Windows
DirectX provides the interface to access the frame buffer and advanced features of the graphics card, which are not provided in the standard Windows GDI graphics interface. When DirectX was introduced, vendors quickly developed drivers that exposed low-level functions of their graphics hardware to the application.

Emulate Graphics Functions in Software
Through the Hardware Emulation Layer (HEL), DirectX is capable of emulating graphics functions in software that are not built into the graphics card. See graphics pipeline.

Which DirectX Version Is Running?
To determine which version of DirectX is installed in your PC, select Run from the Start menu, type in dxdiag and click OK. Look under System Information for the DirectX Version number. See DirectX 10, DirectX 11, GDI, video accelerator and DirectSound.

DirectXInterface      Purpose

 DirectCompute  GPGPU computing

 DirectDraw     2D graphics

 Direct3D       3D graphics

 DirectSound    audio

 DirectSound3D  game audio

 DirectPlay     multi-player games

 DirectInput    game input

 DirectVoice    game audio chat

 DirectShow     streaming media

 DirectVideo    earlier video API
References in periodicals archive ?
DirectX 12 offers a good number of improvements gaming-wise, such as less overheads from DirectX 11 and the capacity to combine the graphics processing powers of AMD and NVIDIA GPUs.
Complete with support for advanced DirectX 12 features like asynchronous compute and explicit multi-adapter, PC gamers the world over will be treated to a high-performance and highly-parallelized game engine perfectly suited to sprawling civilizations designed to win hearts, minds, and the stars.
Luna presents a comprehensive guide to 3D game programming using DirectX 12 software.
Windows 10's launch and the debut of Ashes of the Singularity brought the first hints of DirectX 12 gaming performance, as did Fable Legends, which debuted some weeks later.
The DirectX 12 game programming tools will reportedly improve the visual quality of games on mobile devices, PCs and the Xbox gaming console.
Finally, moving into developer land, Microsoft says that DirectX 11.
The "Trinity" APU, which will be based on the "Bulldozer" x86 core with support for UVD and DirectX 11, is expected to consume less than half the power of today's lowest power AMD A-Series APU, with software drivers optimised for Windows 8.
The ATI Radeon HD 5570 graphics card joins the line of AMD graphics that fully support DirectX 11, as well as ATI Eyefinity multi-display technology and ATI Stream capabilities.
Based on RADEON X300 core technology, users benefit from a variety of features including DirectX 9 vertex and pixel shaders, as well as improved anti-aliasing capabilities.
AMD executed our DirectX 11 transition incredibly well, rolling out a top-to-bottom DirectX 11 product line before our competitor launched their first DirectX 11 part," said Matt Skynner, corporate vice-president and general manager, GPU division, AMD.
The company said the new series of graphics cards provides gamers with an enhanced second-generation, Microsoft DirectX 11-capable architecture for high performance, advanced image quality features and PowerTune power management technology that dynamically adjusts power draw.
Addressing the needs of thin and light notebook PCs, MOBILITY RADEON X300 delivers the perfect blend of DirectX 9 performance and power management for consumer and commercial notebooks.