[Gzz] - 5th (jvk)

[Janne Kujala]

- 5th: Irregu work

Some issues:

Most of the per-vertex-specified parameters need to change 
non-continuously between segments of a QUAD_STRIP. 
For example, the outer and inner edge texture q coordinate ratio 
must match the outer and inner edge length ratio.
Is it a problem if each pair of the vertices needs to be repeated?

Tried a new type of fragment program that computes

    R0 = (fragment is inside ? 1 : 0)
    R1 = DDX(R0)^2 + DDY(R0)^2 
    output color = (R1 > 0 ? 1 : 0)

However, it won't work properly because NV30 computes DDX (DDY) simply
as the difference of right (lower) and left (upper) fragments of a 2x2 
block [http://developer.nvidia.com/docs/IO/3260/ATT/OpenGLforNV30.pdf].

        jvk