static IntPtr KeyboardProc(int code, IntPtr wParam, IntPtr lParam)
{
if (code >= 0)
{
// Since this is a global hook, we don't want to react to
// keypress on every window, so make sure game window is foreground
if (PlatformInvokeUSER32.GetForegroundWindow() == childHwnd)
{
if ((int)wParam == PlatformInvokeUSER32.WM_KEYDOWN)
{
var kbdInfo = (PlatformInvokeUSER32.KBDLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(PlatformInvokeUSER32.KBDLLHOOKSTRUCT));
Keys key = (Keys)kbdInfo.vkCode;
if (key == Keys.F11)
{
// This does not seem to actually work when the overlay isn't loaded
//SteamScreenshots.TriggerScreenshot();
HandleScreenshotRequest(new ScreenshotRequested_t());
}
}
}
}
return(PlatformInvokeUSER32.CallNextHookEx(IntPtr.Zero, code, wParam, lParam));
}
static void Main(string[] args)
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
if (args.Length == 0)
{
return;
}
if (!SteamAPI.Init())
{
MessageBox.Show("Steam API cannot be initialized, exiting.");
return;
}
string exeName = args[0];
string[] procArgs = args.Skip(1).ToArray();
string procArgString = procArgs.Length == 0 ? string.Empty : string.Join(" ", procArgs);
Process proc = Process.Start(exeName, procArgString);
if (proc != null)
{
// Set up screenshot callback and hook
screenshotReadyCallback = Callback <ScreenshotRequested_t> .Create(HandleScreenshotRequest);
SteamScreenshots.HookScreenshots(true);
// Set up global keyboard hook
IntPtr hook = PlatformInvokeUSER32.SetWindowsHookEx(PlatformInvokeUSER32.HookType.WH_KEYBOARD_LL, KeyboardProc,
IntPtr.Zero, 0);
if (hook == IntPtr.Zero)
{
int err = Marshal.GetLastWin32Error();
MessageBox.Show($"Failed to set hook, error {err}");
}
// Wait for window to be created before setting main window handle
// You might need to change this if your game creates several windows
// before settling.
while (proc.MainWindowHandle == IntPtr.Zero && !proc.HasExited)
{
System.Threading.Thread.Sleep(100);
}
childHwnd = proc.MainWindowHandle;
// Run callbacks until child process exits
while (!proc.HasExited)
{
SteamAPI.RunCallbacks();
System.Threading.Thread.Sleep(16);
}
// Unhook before we leave
if (hook != IntPtr.Zero)
{
PlatformInvokeUSER32.UnhookWindowsHookEx(hook);
}
}
else
{
MessageBox.Show("Failed to start game process.");
}
SteamAPI.Shutdown();
}
static bool TakeScreenshot(IntPtr hwnd)
{
bool success = false;
IntPtr hBmp = IntPtr.Zero;
// Get DC of game window
IntPtr hDC = PlatformInvokeUSER32.GetDC(hwnd);
if (hDC != IntPtr.Zero)
{
// Make compatible DC that we can blit to
IntPtr hMemDC = PlatformInvokeGDI32.CreateCompatibleDC(hDC);
if (hMemDC != IntPtr.Zero)
{
// Get size of what we're trying to take a screenshot of
if (PlatformInvokeUSER32.GetClientRect(hwnd, out PlatformInvokeUSER32.RECT rect))
{
int width = rect.right - rect.left;
int height = rect.bottom - rect.top;
// Create bitmap
hBmp = PlatformInvokeGDI32.CreateCompatibleBitmap(hDC, width, height);
if (hBmp != IntPtr.Zero)
{
// Blit the thing
IntPtr hOld = PlatformInvokeGDI32.SelectObject(hMemDC, hBmp);
PlatformInvokeGDI32.BitBlt(hMemDC, 0, 0, width, height, hDC, rect.left, rect.top, PlatformInvokeGDI32.SRCCOPY);
PlatformInvokeGDI32.SelectObject(hMemDC, hOld);
success = true;
}
}
PlatformInvokeGDI32.DeleteDC(hMemDC);
}
PlatformInvokeUSER32.ReleaseDC(hwnd, hDC);
}
if (success)
{
// Use .NET's graphics processing to extract our pixels
using (Bitmap bmp = Image.FromHbitmap(hBmp))
{
// Remember to clean up the native bitmap from earlier
PlatformInvokeGDI32.DeleteObject(hBmp);
// Lock the bitmap data and prepare a buffer
BitmapData bits = bmp.LockBits(new Rectangle(Point.Empty, bmp.Size), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
byte[] buffer = new byte[bmp.Width * bmp.Height * 3];
int i = 0;
unsafe
{
byte *scanline = (byte *)bits.Scan0;
while (i < buffer.Length)
{
for (int j = 0; j < bits.Width; ++j)
{
// The buffer in .NET is BGR, so flip it to RGB when copying
buffer[i++] = scanline[2];
buffer[i++] = scanline[1];
buffer[i++] = scanline[0];
scanline += 3;
}
scanline += bits.Stride - bits.Width * 3;
}
}
// Unlock the bits
bmp.UnlockBits(bits);
// Send it off to Steam
ScreenshotHandle hScreenshot = SteamScreenshots.WriteScreenshot(buffer, (uint)buffer.Length, bmp.Width, bmp.Height);
success = hScreenshot != ScreenshotHandle.Invalid;
}
}
return(success);
}
