3D Display Technology

API stands for application programming interface. It is a source code interface that a computer application provides to support requests for services to be made of it by a computer program. Examples of API are Window API, GoogleMaps API, YouTube API and OpenGL. ABI (Application Binary Interface), is similar to API, but API is usually defined at a higher level.  

GPU stands for Graphics Processing Unit. It is a graphics rendering device. GPUs can sit on top of graphics cards or be intergrated into the motherboard. Modern GPU come from monolithic graphic chips created in the early 1980’s. The two big companies that produce GPU’s are Nvida and AMD.

Shaders are part of the renderer, which are responsible for calculating the colour of an object. They are a set of instructions used by graphic resources primarily to perform rendering effects. There are many types of shaders. Vertex Shaders (which only affect a series of vertices), Geometry Shaders (which can add and remove mesh from vertices) and Pixel Shaders (which calculate the colour of pixels). All three are present in a Universal Shader model. Universal Shader models are present in the latest DirectX and OpenGL.

Render Engines are used at the end of the development process. With everything done, the rendering engine renders it in its final form. It has code and instructions that help to render.

SGI stands for Silicon Graphics. They are company manufacturing high-performance computing solutions. It was founded by James Clark and Abby Silverstone. SGI’s IRIS GL was the dominant API during the early 1990’s. As the market grew and SGI dominance begun to slip away it moved from IRIS GL to OpenGL. OpenGL was cheaply licensed out to its competitors, allowing it to become the industry standard. Even to this day, OpenGL stands as the only 3D graphics standard to be in use across a variety of operating systems. In 1994, James Clark left SGI and founded Netscape with marc Andreessen. In 1998 he moved onto WebMD and in 1999 myCFO.

Direct3D is part of Microsoft’s DirectX API. It’s main competitor is OpenGL. There are multiple API’s, (DirectDraw, DirectMusic, DirectPlay etc.) and DirectX is the generic term used to reference them all. Direct3D is the most widely recognized API in DirectX, and DirectX is sometimes used in place of Direct3D.It has been used in all Microsoft Window’s since Window ‘95 and is also present in Microsoft’s Xbox and Xbox 360. Direct3D can render three dimensional graphics in applications where performance is important. Games are example of such an application. DirectX is frequently changing with a new version practically every year. Here is a comparison between DirectX 9 (released 2002, last updated 2007) and DirectX 10 (released 2006).

OpenGL stands for Open graphics library. It is the industry’s most widely used and supported 2D and 3D graphics application programming interface (API). With the exception of Windows and the Xbox, all operating systems that allow for hardware-accelerated 3D graphics utilize OpenGL as their primary 3D graphics API. It’s main competitor is Direct3D. OpenGL simplifies the development of graphics software and has over 250 different function calls which can be used to draw complex three-dimensional scenes from simple primitives. This is the OpenGL Visualization Programming Pipeline.

DirectX vs. OpenGL
DirectX and OpenGL are the two major API’s. They are similar but different. Essentially anything Microsoft (Windows, Xbox, Xbox 360) uses DirectX primarily and everything else (Non-windows computers, Nintendo consoles, Sony consoles) usually uses OpenGL primarily. Windows being the most widespread operating system means that DirectX is the more widespread of the two. DirectX is designed more as a hardware interface, whilst OpenGL is a rendering system that may be hardware accelerated. So at the core they are different. OpenGL is often seen as the more professional of the two. DirectX is commonly used for gaming purposes. OpenGL is used for animated films. At one point OpenGL were the dominant of the two and DirectX was seen as inferior. Many graphics cards only supported OpenGL and Microsoft was urged to change to it. But DirectX has improved and they are both now widely supported. When comparing the two, there is no real winner as they both get the job done. It depends on what you need it for generally, (DirectX = gaming, OpenGL = animation).