[unlinkr]

So it seems we agree that for the question the OP is actually asking a regex is the appropriate tool.

Great if you can recommend a tool which can solve the task easier. But saying it is "not possible" is unhelpful and confusing. It is just giving lots of people really confused ideas about what is possible and not possible using regexes.

To use your own example: "Can I build my raster engine to draw polygons on screen?"

Not helpful: "No that is simply not logically possible due to the laws of geometry, and you are an idiot for even thinking such a thing is possible"

Helpful: "Yeas, but it is a lot of work if you want to support anti-aliasing, smooth scaling and so on. Using a library like XYZ would probably save you a lot of work in the long run".