the vanilla beginGraphicsTransfer routine only relied on vblank to transfer data to vram
this allowed for a speed of 64 bytes (4 tiles) per frame, which may be a bit slow

this rewritten beginGraphicsTransfer routine also makes use of hblank in order to accelerate the data transfer
the speed of the transfer is quadrupled, which makes it almost viable to load graphics on the fly

i made this because i was surprised by megaman xtreme having sprites load on the fly and i want that too

please if you see any glitch post a comment on here