I probably wouldn't even generate an SDF, instead read the data directly from a 1D texture and fill the anti-aliased line directly in the fragment shader.
Yeah, I meant more in the abstract sense, rather than "create a two-dimensional texture of the distance field", which as you point out would be unnecessary.
You could probably sample all the 1D textures in one pass, and draw all the lines and fills there. One additional nice side effect of this is that you can easily have sequences at different resolutions.
