RGB+A "dual LPE" possible in Karma?

   335   2   0
User Avatar
Member
20 posts
Joined: June 2018
Offline
Hello

I'm wondering if the "dual LPE" syntax described in the OSL docs is supported in Karma? (I wasn't able to get it to work)

OSL Light Path Expressions [github.com]
Good, you got your alpha channel as a separate AOV, but what if you want to put it in the actual alpha channel of an RGBA AOV? You can do that by appending your expression to the standard rgb expression for an AOV. Look at this example:

Output ("beauty.tif", "rgba", "C[SGs]*D*<Ts>*L !C<Ts>*B")
Edited by Dan_Andersen - Sept. 9, 2025 02:51:03
User Avatar
Staff
469 posts
Joined: Sept. 2016
Offline
No, it's not possible with karma (custom alpha has to be its own AOV)
User Avatar
Member
20 posts
Joined: June 2018
Offline
Okay, that's what I suspected - thanks for confirming.
  • Quick Links