No matter whether we've got a low end or high end system, we all expect the realtime 3D revolution to continue until we achieve near parity with reality. The push forward is backed by many factors including pure hardware performance and brilliant advances in techniques for better approximating what we see. But there's another side to the equation beyond just hardware and developers: there is the graphics API.

Unlike CPUs, graphics hardware (GPUs) do not have a common instruction set upon which tools and software can be built. In order to get power of the hardware out to the public, we need a common interface that works no matter what GPU is underneath. It's left to the graphics hardware designer to take the code generated by this application programming interface (API) and translate it into something that their chip can use. Because it's the developer's single point of contact, the graphics API is incredibly important. It defines how much flexibility programmers have in using hardware and shapes the world of high performance realtime 3D graphics.

Some of the key work done through graphics API is taking descriptions of 3D objects in a 3D world, sending those objects and other resources to the hardware, and then telling the hardware what to do with them. There is sort of a step by step process that needs to be followed that we generally call a pipeline. Graphics API pipelines have different stages where different work is done. Here's the general structure of a 3D graphics pipeline:

First vertex data (information about the position of the corners of shapes) is taken in and processed. Then those shapes can then be further manipulated and re-processed if needed. After this, 3D objects are broken down from 3D shapes by projecting them into 2D fragments called pixels (this step is called rasterization), and then these pixels are each processed by looking up texture information and using lighting techniques and so on. When pixels are finished processing, they are output and displayed on the screen. And that's the mile high overview of how 3D graphics work.

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