Hey guys, I know this is my first post on here, but I want to get into a coding language. I've coded in AS3 and VB but nothing very serious. Also some basic php tuts online :P My primary skill is animation. But Flash to me doesn't cut it. Any animation studio that is serious doesn't actually use flash. Only cartoons use it.

I want to code an animation program, I'd learn the language over a few years. and work on that project the whole time I'm learning. But I want to know what Language would be best suited for the projects needs.
Compatibility: Windows and Mac
(this makes me want to do an online based software, but I'm not sure if those are able to do all the same things that flash could, like having large files, and even then I don't know how compatible that is. I heard Html5 isnt all that compatible yet, and I would like it so you dont need internet connection to produce a animation, just icing on the cake if you're doing a jointed work you can just send the animation in real time.)

It would have to work with a PenTablet. If anyone can sujest a language to me, I'll definitely do my research on it. But I really only know programs like Delphi and C# C++, and they aren't for Mac really.