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A user asked me, "From what I noticed, the available materials are
defined through shaders. What I had in mind was defining materials
through an OpenGL call such as glMaterial (<a
href="http://www.opengl.org/sdk/docs/man/xhtml/glMaterial.xml"
target="_blank" style="color: rgb(42, 93, 176);">http://www.opengl.org/sdk/<wbr>docs/man/xhtml/glMaterial.xml</a>).
This could of course be packaged as a shader but it would replicate
functionality that is already available from the lower level of OpenGL."<br>
<br>
I asked David Scherer about this, and he replied that this was the
approach attempted in Visual 4 - adding OpenGL features that look like
what you want on paper, but that while OpenGL can _represent_ all kinds
of material properties, it can only render a few reasonably accurately
(because it does everything at vertex level, among other limitations).
For everything else, you need shaders. This is why Visual 5 uses
shaders for materials.<br>
<br>
Bruce Sherwood<br>
<br>
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