Fix rotation and subpixel placement
Fix rotation and subpixel placement

Add subpixel shift to the points after rotation transformations to fix
rotations and subpixel accuracy.

Distrotech/libass,torque/libass,asimonov-im/libass,rhlee/libass,stps/libass,grigorig/libass,mwgoldsmith/libass,tgoyne/libass,vault/libass,pigoz/libass-ct,sanyaade-g2g-repos/libass,tgoyne/libass,Akemi/libass,grigorig/libass,astiob/libass,rhlee/libass,stps/libass,xbmc/libass,Akemi/libass,asimonov-im/libass,Akemi/libass,libass/libass,Distrotech/libass,richardpl/libass,mwgoldsmith/libass,richardpl/libass,sanyaade-g2g-repos/libass,torque/libass,pigoz/libass-ct,MrSmile/libass,mwgoldsmith/libass,sanyaade-g2g-repos/libass,rhlee/libass,vault/libass,stps/libass,blinkseb/libass,libass/libass,ShiftMediaProject/libass,Distrotech/libass,torque/libass,richardpl/libass,astiob/libass,blinkseb/libass,xbmc/libass,pigoz/libass-ct,ShiftMediaProject/libass,MrSmile/libass,blinkseb/libass,tgoyne/libass