[Feature Request] High-resolution OpenGL renderer

[lonelycare]

With this enabled the GBA screen is rendered on the GPU instead of the usual software rendering, which allows scaling up beyond the usual 240×160 resolution without thrashing the CPU.

This lets rotation and scaling effects look much cleaner and allows the “mode 7” effect to be even more impressive.

[hizzlekizzle]

Yeah, we've discussed this some and the general reduction in portability moving from software rendering to hardware rendering is a significant drawback.