// converts a texture to monchrome and outputs it in alpha
xps.1.1

def c0, 1,1,1,1
def c1, 0.3, 0.59, 0.11, 0.0

tex t0

// convert to luminance
dp3 r1, c1, t0

// copy color over
mov r0.rgb, t0
// copy luminance to alpha
+mov r0.a, r1.a