Transparent corners

Hi folks

My doubt is, how do I make an alpha capable surface with same screen
format?
I’m trying to make ‘transparent’ corners but I always see them.
(I draw lines with SDL_gfx with colors 0,0,0,0 or 255,255,255,0 to give
borders a circular transparent look)
I debugged (printf ;)) my sfc->fmt->Amask and is always 0, if I change
it, I get all things black :frowning:
I tried also that amask = ~(fmt->Rmask | fmt->Gmask | fmt->Bmask) trick
and got same result (all black)–
pirata <@pirata>
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