Free Software & Other Computer Graphics Resources
			
In addition to the SRGP and SPHIGS packages which supplement this text,
there is a large amount of free or very inexpensive computer graphics
software available.  Many of these packages are available on computer
bulletin boards - such as Compuserve - but the largest repository by far
is the Internet.  If you're unfamiliar with accessing and navigating the
Internet, we recommend consulting books such as

	Krol, Ed, The Whole Internet,
	O'Reilly & Associates, Sebastopol, CA, 1992.
	
Essential things to know about the Internet are how to access ftp sites
and how to read network news. Armed with those skills you can acquire
valuable graphics-related software and data to use in your course. An
excellent overview of the abundance of available graphics resources can be
found in this directory in the file CGResources.  As stated there, it is
a resource listing which appears weekly in the network newsgroup,
comp.graphics. Besides the resource listing, this newsgroup contains many
items of general interest to the computer graphics community and you are urged
to consult it regularly.

Two examples of software available on the Internet are represented by the
directories Rayshade and SIPP. Rayshade is a package which implements the
ray tracing techniques described in Chapter 14. The Readme file in the
Rayshade directory describes the features of the package. Other files in
that directory are images produced by the Rayshade package.

SIPP (SImple Polygon Processor) is a library for creating 3-dimensional
scenes and rendering them using a scan-line z-buffer algorithm, as described
in Chapter 13. A scene is built up of objects which can be transformed with
rotation, translation and scaling.  The objects form hierarchies where each
object can have arbitrarily many subobjects and subsurfaces.  A surface is a
number of connected polygons which are rendered with either Phong, Gouraud or
flat shading.  An image can also be rendered as a line drawing of the polygon
edges without any shading at all. More information on SIPP can be found in the
Readme file in the SIPP directory. There, too, are examples of images produced
by SIPP.

These packages and many others can be obtained from many sites on the Internet.
Consult the CGResources file for specific Internet addresses.

The file named FAQ contains a list of frequetly asked questions (and answers)
about computer graphics.