If you have the means, there are a good # of LED light set-ups that attach to your feeder, or tree or whatever that will give some illumination of the feeding area. I have shot hogs that way, but make sure where you hunt, that it is legal. A clear sky on a full moon night works if you are not under a heavy forrest canopy and have a scoped rifle with a good sized objective to allow light in.
If you spot light, try to either place a colored lens over the light or don't shine directly at the hogs as soon as you turn the light on. They will generally scatter pretty quickly once they are hit with a zillion candle power light at night. Try shining the light up at the sky, and slowly bring it down onot the pigs, enough to see them for a shot. This works well if you have a partner with you.
Good luck.