Bird-like glints of light move across the sky like a vortex in broad daylight.

Was waiting in line at the Pollo Regio on Buckner across from Walgreens in Pleasant Grove(Dallas). I thought I saw some birds circling at first but then I noticed it was just glints of light spinning horizontally across the sky. Like a tornado of them, but with enough distance between them to still distinguish the sky and moving clouds clearly. It was a vortex shape with depth that appeared like white birds. It moved across the horizon just like a tornado in the sky then vanished altogether.
I had been watching the clouds roll by while I waited so I thought maybe it was just visual interference of some sort, but nothing like that followed my eyes when I looked away, and it was clearly moving through the sky in a single direction while parts of the light that moved like birds just vanished until it was all gone.
Less like a craft and more like an entity in itself, or something outside of conventional