I was meditating

It's easy for me to detach from self-concern
But meditating is often uneventful, just nothing special.
I'm sure that it has some positive effects on my body and mind though

Last month or so, I was meditating as usual, observing the imagery brought to my mind without any interference of will or imagination. Usually, it's often faces or sceneries morphing into new faces/sceneries as if it was constantly unrolling. Kind of neat.

That time it was different, I became intensely transfixed and a load of beautifully complex symbols with very pleasant colors showed up like a high-speed stream. It felt like I never saw these colors before, their tint or hue was always someonewhat off from the colors I knew and it made them more beautiful, divine even.

The lines forming the symbols where white on color backgrounds, they had the same symbolic potency as crop circles but x1000 and they flashed before me extremely fast.

Any clues what this was?