Using glman - Graphics Shaders - page 69

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Using glman

Shaders, like many other areas in graphics, have many complexities in their
structure and options, and one of the best ways to learn them is simply to try
out ideas, choices, and different parameters in the shaders you write. However,
exploring shaders in this way can be time-consuming when you have to go
through the entire edit-compile-link-run cycle for each change you want to test
in the shader. In order for you to try out many options and ideas for shaders
with a very short turnaround cycle, the glman tool provides a handy OpenGL
program substitute that lets you change shader code and see the results very
quickly, especially since it also lets you experiment with the values of uniform
variables as shader parameters. The cycle of experimentation for developing
shaders with and without glman is shown in Figure 4.1.
To use glman , you need to create a GLIB file. The name GLIB stands for
“GL Interface Bytestream,” and a GLIB file is a scene description script whose

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