GetPointerPenInfo function to get pen pressure - how?

Question

I am trying to use the GetPointerPenInfo() function to read pen pressure from the stylus (testing with Wacom Intuos). However, the returned pressure value in the POINTER_PEN_INFO structure is always 0. Do I need to use any other functions along with this one, or perhaps a better way to handle that in general, with WinApi ? Any help and experience with pen pressure would be much appreciated.

Answer 1

I know this is an old question but I found it while searching for a similar problem I was having.

GetPointerPenInfo is normally only supposed to work on pointers of type PT_PEN. If GetPointerPenInfo is called on a non-pen pointer, then it'll return 0 (meaning it failed). So you should call GetPointerInfo first, check if it's pointerType is PT_PEN, then call GetPointerPenInfo.

In your case based on the comments, since you were only receiving Mouse pointer updates I'd double check that pen pressure functionality is actually working in some other program with your pen, especially since you mention Wacom; in my case it wasn't and that helped me figure out that my Wacom tablet needed to have Windows Ink enabled in its options to get the PT_PEN pointer updates.

If some of the other values in your structs are 0, especially if all of them are 0 after a certain point in your structs, I'd check to make sure they're set up correctly. In my case I was doing this in C# and my structs were not set up correctly at certain spots, so those spots and everything afterwards was 0.