This question involves Win32, so it isn't exactly DirectX, but the line between the two is pretty blurred, so this seemed the appropriate forum. If I call CreateWindow passing it a width and height, the resulting window's non-client rectangle has this width and height, not the client window. To get the appropriately sized client size rectangle, I have to do a pretty hackish, though thus far reliable, trick:

// psuedo code
HWND hwnd = CreateWindow(.., width, height, ...);
RECT almost;
GetClientRect(hwnd, &almost);
SetWindowPos(hwnd, 0, 0, 0, 
             2*width-almost.right, 2*height-almost.bottom, 
             SWP_NOMOVE);

The trick basically assumes that the non-client area is bigger than the client area by a constant amount, so you can know how much to overshoot to get the right client size. I know this has to be a common problem, so is there a better way to do this? I tried to find a deterministic way to translate a desired client rectangle into the size of its surrounding non-client window, but I could find none on MSDN or elsewhere. Any ideas? Thanks

You can also call AdjustWindowRect before creating your window, just insert the styles and a TRUE if you've got a menu.

Awesome! This is exactly what I tried in vain to find.