moving SDL video surface

Question

Does anyone know how to move my SDL.net video surface around the screen programtically?

Surface videoContext = Video.SetVideoMode(1024, 768, 32, false, false, false, true, true);

var a = System.Windows.Forms.Control.FromHandle(Video.WindowHandle);
var b = System.Windows.Forms.NativeWindow.FromHandle(Video.WindowHandle);

I can't find any properties in Surface or Video which do the job, and FromHandle is returning Null.

The window is initializing falling off the bottom of the screen.

Any ideas?

Update:

I've seen this code but can't work out an equivilent C# implimentation. Can anyone help?

#ifdef WIN32
#include <SDL_syswm.h>
SDL_SysWMinfo i;
SDL_VERSION( &i.version );
if ( SDL_GetWMInfo ( &i) ) {
  HWND hwnd = i.window;
  SetWindowPos( hwnd, HWND_TOP, x, y, width, height, flags );
}

Failing that, how much work is involved in including some c++ in my c# project?

Thanks.

Answer 1

Judging by the C++ code you've found, you could P/Invoke the Win32 SetWindowPos function and pass the Video.WindowHandle handle (as well as your size and position parameters) since there doesn't appear to be a solution provided by .NET.

Answer 2

You'll need these declarations:

    private static IntPtr HWND_TOP = IntPtr.Zero;
    private static int SWP_FLAGS = 0x004 | 0x0010;
    [System.Runtime.InteropServices.DllImport("user32.dll")]
    private static extern bool SetWindowPos(IntPtr hWnd, IntPtr after, int x, int y, int width, int height, int flags);

Usage:

    SetWindowPos(Video.WindowHandle, HWND_TOP, x, y, width, height, SWP_FLAGS);

where x and y are in screen coordinates. Use Control.PointToScreen() if necessary.