If I want to mix two materials together based on an image, I currently do it this way:
void mixpict decal 7 foo bar grey mask.hdr . frac(Lu) frac(Lv) 0 0
In this case,
mask.hdr is a black and white mask. The “grey” function, according to the refman, takes three arguments, RGB, and in this case uses the greyscale value of the
mask.hdr to figure out whether to show
Is it possible to use another function in place of
grey that reads transparency values of the pixels in the hdr? From my understanding of the sentence in the refman, this is not possible as only RGB is taken as inputs, but I thought I’d ask. This would save me the time to create another dedicated greyscale mask, and be very useful when creating materials for “decal” patterns.
Thanks in advance