Issues trying to Compose an image with masked channels

[Ofnuts]

(05-11-2023, 05:17 PM)pronay Wrote: I'm trying to avoid this being an XY problem, what I want to achieve remains the same as my original post.

I am trying to write a script that can essentially do what the decompose to R,G,B,A and then compose a new image using R and G as-is but with B and A channels using a mask value of 255.

If the new approach being suggested (using layers filled with #FF0000, ##00FF00 and ##0000FF in multiply mode) is the better approach, I can try this on my end. I'll use alpha-to-selection and then apply a 255 mask value to the drawable. 

I'll be giving this a go and updating my results here

If you want to "fill" the alpha channel with 255, you have to wonder what the colors of the transparent-now-opaque pixels is. In Gimp th is is normally the current "background" color, and filling the channel with 255 is the same as removing it.

And filling the image with B=255 is the same just adding a layer filled with pure blue (#0000FF) and put in in "Addition" mode, so you don't even need the decomposition.