It’s already a solved problem if you want to keep using the software you already wrote, and never do anything different. (Nobody is stopping people from running OS X 10.13 indefinitely on their 1x displays.)

If you want to rearchitect your whole text / vector graphics rendering pipeline to take proper advantage of GPUs, then you are going to be much happier with your life if you don’t have to double your work to support legacy hardware.

I would love to see Apple implement this kind of thing http://w3.impa.br/~diego/projects/GanEtAl14/