MAMEWorld Forums - EmuChat - Re: How to set a custom window size for a game in Mame?

> Thanks man, worked like a charm.

Please be aware that there are multiple aspect ratios at play here: The Display Aspect Ratio (DAR), Source Aspect Ratio (SAR), and Pixel Aspect Ratio (PAR).

In this day and age, the Display AR and Source AR are identical, which gives a square (1:1) Pixel AR.

That the vast majority of arcade games didn't use resolutions that resulted in a square Pixel AR, and equally, the relevant artwork was designed with whatever PAR the game had in mind so that anything intended to be displayed as a circle or square would show "true".

A horizontal-orientation game with a resolution of 320x240 has a SAR of 4:3, or 1.3333~, which allows for perfectly square pixels on standard arcade CRT monitors, which themselves had a DAR of 4:3. To calculate PAR, you divide the DAR by the SAR. In this case, 1.3333/1.3333 gives you 1, meaning that the resulting on-screen pixels are perfectly square. Your intended configuration works fine in this case.

Meanwhile, a horizontal game with a resolution of 320x224 has a SAR of 10:7, or 1.428571~, but is still being shown on a CRT with a DAR of 1.3333~. This gives a resulting PAR of 0.9333~, or pixels that are slightly wider than they are tall.

With the above example, the PAR is still close enough to 1 that you might not necessarily notice it.

But let's use the quintessential example of Capcom's CPS-2 hardware, which hosted quite a number of revered fighting games and other classic 2D titles from the 90's. It operated at a resolution of 384x224, for a Source Aspect Ratio (SAR) of 1.714285~. The system was always intended to be displayed on a standard 4:3 monitor. Dividing it out, we get a Pixel Aspect Ratio (PAR) of 0.7777~, which means the pixels are almost 25% shorter than they are wide - or, if you prefer, they're almost a third wider than they are tall.

Perhaps you're a chubby-chaser. Could be that you have a friend for Fat Chun-Li. Hey, we don't kink-shame around here, if that's your thing then go off, fam. But it just seems a bit weird to go out of your way to want accurate emulation by way of MAME, then throw it all out the window when it comes to what you're seeing with your eyes, is all.