Graphics Reference
In-Depth Information
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OpenGL Shader Evolution
In its early days, computer graphics had no standard programming models.
Vendors provided a low-level interface to their hardware, and each person or
group then developed their own approach to taking geometry and appear-
ance information and applying their particular algorithms to create a screen
display. It was fun (in a geeky sort of way), but not very efficient or portable.
While many of the images created in this period might seem very simple by
today's standards, a lot of work went into them, and the basic ideas generated
in those days still impact us today.
Early atempts to reduce the amount of development work needed for
production focused on building graphics standards, but the standards gener-
ally provided only a least-common-denominator level of functions. However,
as standards developed, they led to a growing understanding of the funda-
mental operations needed in the graphics process and provided a rising level
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