ps_2_0
// generates tunnel tex coordinates
// calculates z (tex v) coordinate
dcl t0
dcl_2d s0
def c0,-0.5,-0.5,0.5,4
def c5,-1.5500992e-006, -2.1701389e-005,  0.0026041667, 0.00026041668
def c6,-0.020833334f, -0.12500000f, 1.0f, 0.50000000f
add r0,t0,c0
mul r0.x,r0.x,r0.x
mul r0.y,r0.y,r0.y
add r0.x,r0.x,r0.y
rsq r0.y,r0.x
rcp r0.x,r0.y
mul r0.x,r0.x,c0.w
sincos r2.xy,r0.x,c5,c6
rcp r2.z,r2.y
mul r0.x,r2.x,r2.z     // cos/sin
mul r0.x,r0.x,c0.z
texld r1,t0,s0
mov r1.y,r0.x
mov oC0,r1

