Thanks for your kind words, Hyllian. I'll experiment with which flavours of xBR I like best until 0.2.97.25 comes out with all of them added.
I'll have to keep recompiling because I don't want to mess up the menu any more than I already have, can anyone tell me what I missed? When I select 3xBR or 4xBR there's no indicator to say which SoftFX option is selected. It's a small thing, I know, but just in case I find another algorithm in future and want to experiment...
I'm still astounded that it works. All I did was copy the code, copy the function parameters from hq3x, then I just looked at how the other algorithms were added to the menu and copied that, although I didn't do that perfectly.
My main motivation for doing it was that I only have ancient onboard graphics in my PC, so HLSL and other shaders run really slowly.