You can detect TrueVGA with GetSystemMetrics, which will return these values in TrueVGA.
GetSystemMetrics(SM_CXSCREEN) //480
GetSystemMetrics(SM_CYSCREEN) //640
In normal VGA mode GetSystemMetrics will return 240 and 320 respectively.
You can avoid having to scale down the stylus coordinates if you add this resource to your project.
To add the HI_RES_AWARE resource item to your program
1. From the Insert menu, select Resource.
2. Click the Custom button.
3. Enter CEUX for the resource type.
4. Set the resource data to 01 00.
5. Click the Properties tab.
6. Rename the item to "HI_RES_AWARE", including quotes. (If the quotes are omitted, HI_RES_AWARE will be incorrectly defined as a numeric value in resource.h, and you will need to go back and delete the line from resource.h.)
7. Deselect the external file checkbox.
Taken from this link.
http://msdn.microsoft.com/library/defau ... reness.asp