_SETALPHA Question

[TerryRitchie]

SETALPHA Level%, _RGBA32(255, 0, 0, 0) TO _RGBA32(255,0,0,255), Image&

More flexibility than just assuming "do them all".  

What if you only wanted to change a single value's alpha?

Then that is where _RGBA32 would come into play. I definitely see the benefit of controlling individual alpha levels. What I envision is when _SETALPHA sees _RGB32 it assumes all alpha levels for the given color instead of the default 255 that is assumed with _RGB32.

_SETALPHA 0, _RGB32(255, 0, 0), Image& '           all alpha levels of red set to 0
_SETALPHA 0, _RGBA32(255, 0, 0, 255), Image& ' only alpha level 255 of red set to 0

I don't know, perhaps I'm overthinking this.