DirectX - History

History

In late 1994, Microsoft was ready to release Windows 95, its next operating system. An important factor in the value consumers would place on it was the programs that would be able to run on it. Three Microsoft employees – Craig Eisler, Alex St. John, and Eric Engstrom – were concerned because programmers tended to see Microsoft's previous operating system, MS-DOS, as a better platform for game programming, meaning few games would be developed for Windows 95 and the operating system would not be as much of a success.

DOS allowed direct access to video cards, keyboards, mice, sound devices, and all other parts of the system, while Windows 95, with its protected memory model, restricted access to all of these, working on a much more standardized model. Microsoft needed a way to quickly let programmers get a solution; the operating system was only months away from being released. Eisler (development lead), St. John, and Engstrom (program manager) worked together to fix this problem, with a solution that they eventually named DirectX.

The first version of DirectX was released in September 1995 as the Windows Games SDK. It was the Win32 replacement for the DCI and WinG APIs for Windows 3.1. DirectX allowed all versions of Microsoft Windows, starting with Windows 95, to incorporate high-performance multimedia. Eisler wrote about the frenzy to build DirectX 1 through 5 in his blog.

Initial adoption of DirectX by game developers was slow. There were fears that DirectX could be replaced as WinG had been, there was a performance penalty in using Windows over DOS, and there were many die-hard DOS programmers.

DirectX 2.0 became a component of Windows itself with the releases of Windows 95 OSR2 and Windows NT 4.0 in mid-1996. Since Windows 95 was itself still new and few games had been released for it, Microsoft engaged in heavy promotion of DirectX to developers who were generally distrustful of Microsoft's ability to build a gaming platform in Windows. Alex St. John, the evangelist for DirectX, staged an elaborate event at the 1996 Computer Game Developers Conference which game developer Jay Barnson described as a Roman theme, including real lions, togas, and something resembling an indoor carnival. It was at this event that Microsoft first introduced Direct3D and DirectPlay, and demonstrated multi-player MechWarrior 2 being played over the Internet.

The DirectX team faced the challenging task of testing each DirectX release against an array of computer hardware and software. A variety of different graphics cards, audio cards, motherboards, CPUs, input devices, games, and other multimedia applications were tested with each beta and final release. The DirectX team also built and distributed tests that allowed the hardware industry to confirm that new hardware designs and driver releases would be compatible with DirectX.

Prior to DirectX, Microsoft had included OpenGL on their Windows NT platform. At the time, OpenGL required "high-end" hardware and was focused on engineering and CAD uses. Direct3D was intended to be a lightweight partner to OpenGL, focused on game use. As 3D gaming grew, OpenGL evolved to include better support for programming techniques for interactive multimedia applications like games, giving developers choice between using OpenGL or Direct3D as the 3D graphics API for their applications. At that point a "battle" began between supporters of the cross-platform OpenGL and the Windows-only Direct3D. Incidentally, OpenGL was supported at Microsoft by the DirectX team. If a developer chose to use OpenGL 3D graphics API, the other APIs of DirectX are often combined with OpenGL in computer games because OpenGL does not include all of DirectX's functionality (such as sound or joystick support).

In a console-specific version, DirectX was used as a basis for Microsoft's Xbox and Xbox 360 console API. The API was developed jointly between Microsoft and Nvidia, who developed the custom graphics hardware used by the original Xbox. The Xbox API is similar to DirectX version 8.1, but is non-updateable like other console technologies. The Xbox was code named DirectXbox, but this was shortened to Xbox for its commercial name.

In 2002, Microsoft released DirectX 9 with support for the use of much longer shader programs than before with pixel and vertex shader version 2.0. Microsoft has continued to update the DirectX suite since then, introducing shader model 3.0 in DirectX 9.0c, released in August 2004.

As of April 2005, DirectShow was removed from DirectX and moved to the Microsoft Platform SDK instead.

DirectX has been confirmed to be present in Microsoft's upcoming Windows Phone 8.