Editing Direct3D (section)

==Direct3D 2.0 and 3.0==
In 1992, Servan Keondjian, Doug Rabson and Kate Seekings started a company named RenderMorphics, which developed a 3D graphics API named [[Reality Lab]], which was used in medical imaging and CAD software.<ref>{{cite web|url=http://www.qubesoft.com/#clients-team-and-tech|title=Qube Soft Management Team|publisher=qubesoft.com|date=2017-04-04|access-date=2017-04-05|archive-url=https://web.archive.org/web/20170406110841/http://www.qubesoft.com/#clients-team-and-tech|archive-date=2017-04-06|url-status=dead}}</ref>
Two versions of this API were released.<ref name=":2" /> Microsoft bought RenderMorphics in February 1995, bringing its staff on board to implement a 3D graphics engine for [[Windows 95|Windows&nbsp;95]].<ref>{{cite web |last=Prosise |first=Jeff |date=May 16, 1995 |title=Joining the Multimedia Party |url=https://books.google.com/books?id=D4gTpBgpFgUC&dq=pc+magazine+windows+nt+3.5+opengl&pg=PA152 |access-date=2022-08-20 |website=[[PC Magazine]]}}</ref> The first version of Direct3D shipped in '''DirectX 2.0''' (June 2, 1996) and '''DirectX 3.0''' (September 26, 1996).

Direct3D initially implemented an "[[Immediate mode (computer graphics)|immediate mode]]" 3D API and layered upon it a "[[retained mode]]" 3D API.<ref>{{cite web |last=Thompson |first=Nigel |date=August 1996 |title=Building a Scene Using Retained Mode Direct3D |url=https://ubm-twvideo01.s3.amazonaws.com/o1/vault/GD_Mag_Archives/GDM_AugSept_1996.pdf |archive-url=https://web.archive.org/web/20210126031359/https://ubm-twvideo01.s3.amazonaws.com/o1/vault/GD_Mag_Archives/GDM_AugSept_1996.pdf |archive-date=2021-01-26 |url-status=live |access-date=2022-08-20 |website=[[Game Developer Magazine]]}}</ref> Both types of API were already offered with the second release of Reality Lab before Direct3D was released.<ref name=":2" /> Like other DirectX APIs, such as [[DirectDraw]], both were based on [[Component Object Model|COM]]. The retained mode API was a [[scene graph]] API that attained little adoption. Game developers clamored for more direct control of the hardware's activities than the Direct3D retained mode could provide. Only two games that sold a significant volume, ''[[Lego Island]]'' and ''[[Lego Rock Raiders (video game)|Lego Rock Raiders]]'', were based on the Direct3D retained mode, so Microsoft did not update the retained mode API after DirectX 3.0.

For DirectX 2.0 and 3.0, the Direct3D immediate mode used an "execute buffer" programming model that Microsoft hoped hardware vendors would support directly. Execute buffers were intended to be allocated in hardware memory and parsed by the hardware to perform the 3D rendering. They were considered extremely awkward to program at the time, however, hindering adoption of the new API and prompting calls for Microsoft to adopt OpenGL as the official 3D rendering API for games as well as workstation applications.<ref>{{cite web |last=Berkes |first=Otto |date=April 12, 2015 |title=DirectX |url=https://ottoberkes.wordpress.com/2015/04/12/directx |access-date=2022-08-22 |website=Otto Berkes’ weblog}}</ref> (see OpenGL vs. Direct3D)

Rather than adopt OpenGL as a gaming API, Microsoft chose to continue improving Direct3D, not only to be competitive with OpenGL, but to compete more effectively with other proprietary APIs such as [[3dfx]]'s [[Glide API|Glide]].

From the beginning, the immediate mode also supported [[Microsoft Talisman|Talisman]]'s [[tiled rendering]] with the BeginScene/EndScene methods of the IDirect3DDevice interface.