Is there API to know screen ratio?

Retrieve the width and height of the screen, divide them to get the aspect ratio.

That'll only work if the screen is set to the proper resolution, it won't actually tell you the dimensions of the monitor itself?

You need to use the monitors built-in interface, or the video card driver to do that I thought?

He didn't ask for the monitor size, only the ratio.

Hello,

Best way may be to get the screen DC and use GetDeviceCaps to find the pixels (VERTRES, HORZRES) and pixels per inch (LOGPIXELSX, LOGPIXELSY) of X and Y direction. From these data, it is easy to calculate the aspect ratio.

Better still, GetDeviceCaps, when called with parameter HORZSIZE / VERTSIZE returns the entire width / height of physical screen.

HDC hDC = ::GetDC(NULL);
int nWidth = GetDeviceCaps(hDC, HORZSIZE);
int nHeight = GetDeviceCaps(hDC, VERTSIZE);
CString sRatio;
sRatio.Format("Width to Height ratio is %d:%d", nWidth, nHeight);
pDC->TextOut(0, 0, sRatio);
::ReleaseDC(NULL, hDC);

Regards,
Pravin.

Hello,

I have checked with various resolution settings. All the time, monitor aspect ratio was returned as 320:240. Are you sure that your monitor installation settings are correct?

I must admit that I have checked with the code snippet I had earlier posted and not using (VERTRES, HORZRES) and (LOGPIXELSX, LOGPIXELSY). But that also can be easily checked. I do not feel that it will yield a different answer.

Regards,
Pravin.