Image via Wikipedia
Let's look at the difference and while we're at it, look at the common attributes found in the three classes of pipelines: production, material and approval.
If one were to decompose the CG production process into a more generalized graphic design process, one could see that a simplified production pipeline in graphic arts is comprised of:
- acquisition of assets
- impression aka reproduction aka rendering
The answer is there are technology pipelines within the realm of computer science at both the application and the hardware level, but these are not CG pipelines as such. Recall that in article #0018, Understanding Pipelines we looked at how Silicon Graphics introduced the hardware graphics engine, or graphics pipeline, in the early 1980's. The use of data piping within software and hardware is an essential part of today's CG technology. It is the most likely origin of the word "pipeline" to describe the production processes used in computer graphics today.
When frying an egg one gathers the egg, the pan and the oil in one spot, fires up the heat, oils the pan, breaks the egg in the pan and let's it warm and solidify, then flips (or not) the egg once and calls it done. This is a process, not a pipeline. The reason is there is no step by step evolution of the egg being fried.
One could argue that frying an egg can be broken down into a series of tasks. The distinction is that dividing these tasks into separate processes is not meaningful when it comes to frying an egg but can be beneficial when baking a cake. So a pipeline is comprised of a sequence of processes that can flow in a linear or parallel nature relative to one another.
As this example illustrates, the processes of computer graphics together comprise a pipeline. Just as some computer software procedures can be linked together to form a pipeline for processing data, so the procedures in computer graphics are tied together to make a pipeline. However, they are not a pipeline until they are tied together.
For example, the surface modeling process requires personnel with specific skills and abilities using tools with specific capabilities while observing specific work procedures governing not only the process but also the movement of the assets in and out of the modeling phase.
Less obvious is that the dimension of procedure lends itself to partial automation through the use of technology. A pipeline can exist with little or no automation of procedures for moving data through the system, but it will suffer from the vagaries of human error and negligence. As Mr. Bettis points out, this is an area that should be automated. He believes it so strongly that in his thesis he makes no allowance for non-automated implementation of policies and procedures related to the movement of the product through the pipeline. The degree a company can and should invest in this automation depends on factors we will discuss in a future article.
While the pipeline IS NOT the technology, as a technological art, the computer graphics pipeline depends a great deal on technology. We will explore these ideas further as we discuss in detail the three classes of pipelines: the production pipeline, the material pipeline, and the approval pipeline.
Bettis, Dane Edward "Digital production pipelines: examining structures and methods in the computer effects industry", Texas A&M University, http://txspace.tamu.edu/handle/1969.1/2406?show=full, 2005; A useful examination of the digital pipeline with specific examples of pipeline structures.