How do I access the size of a sprite?

I’m trying to implement this now but it’s still not showing up in the editor for some reason…

I changed the line in Build.cs, then I selected New C++ Class… created a class called SpriteFunctions, pasted the code in, changed the include and _API to the name of my project, saved…

Then I went into the editor and selected Refresh Visual Studio Project, which I assume is what I’m meant to do after every time I change any C++? Seems to make sense.

After that, Visual Studio gives a message saying that the solution has been modified outside the environment, though it seems to have given me at least 2 different messages in this situation… one with the option to “Reload” the updated solution from disk (which sounds like what I want) and another with a “Save As…” option that sounds similar. I assume I’m not supposed to build in Visual Studio, and when I try it it predictably doesn’t compile right.

So I’m not sure what’s wrong at this point… I can’t find the function by right-clicking, turning Context Sensitive off and typing the name. I’ve checked multiple times and everything seems fine. I did miss the _API bit before but changing that didn’t fix it.