> According to an old blog entry from Aaron Giles, the value for the -prescale
> parameter is an integer from 1 to 8.
> But in practice, I think the maximum is limited by the resolution of your monitor.
> For example street fighter has a resolution of 384 × 224.
> Assuming a typical monitor with 1920 x 1080 resolution...
> If you set prescale 1, the screen is rendered at 384×224 before scaling up to your
> monitor resolution and...
> prescale 2 = 768 x 448 before scaling up
> prescale 3 = 1152 x 672 before scaling up
> prescale 4 = 1536 x 896 before scaling up
> prescale 5 = 1920 x 1120 before scaling up
> Note that the vertical at prescale 5 is taller than the monitor's native
> 1120 > 1080
> So I believe that the highest prescale that would work for Street Fighter and a 1920
> x 1080 monitor is prescale 4.
> Controls the size of the screen images when they are passed off to the graphics
> system for scaling. At the minimum setting of 1, the screen is rendered at its
> original resolution before being scaled. At higher settings, the screen is expanded
> by a factor of before being scaled. With -video d3d, this produces a less blurry
> image at the expense of some speed. The default is 1.
When i run the mame -prescale x command beyond value 3 from command line it says 'invalid command, reverting to 1'.