/// <summary>Captures a screenshot of a window using Windows GDI</summary>
/// <param name="handle">handle of the window to capture</param>
/// <returns>the captured window image</returns>
private static Image CaptureWithGDI(Workflow wfgdi, IntPtr handle, out Rectangle windowRect)
{
DebugHelper.WriteLine("Capturing with GDI");
windowRect = CaptureHelpers.GetWindowRectangle(handle);
Image windowImageGdi = null;
if (wfgdi.ActiveWindowClearBackground)
{
windowImageGdi = CaptureWindowWithGDI(wfgdi, handle, out windowRect);
}
if (windowImageGdi == null)
{
using (new Freeze(wfgdi, handle))
{
windowImageGdi = Screenshot.CaptureRectangleNative(windowRect);
}
Image result = RemoveCorners(handle, windowImageGdi, null, windowRect);
if (result != null)
{
windowImageGdi = result;
}
}
return(windowImageGdi);
}
/// <summary>Remove the corners of a window by replacing the background of these corners by transparency.</summary>
private static Image RemoveCorners(IntPtr handle, Image windowImage, Bitmap redBGImage, Rectangle windowRect)
{
if (ZAppHelper.IsWindows8())
{
// Windows 8 UI does not have round corners
return(windowImage);
}
const int cornerSize = 5;
if (windowRect.Width > cornerSize * 2 && windowRect.Height > cornerSize * 2)
{
DebugHelper.WriteLine("Clean transparent corners");
if (redBGImage == null)
{
using (Form form = new Form())
{
form.FormBorderStyle = FormBorderStyle.None;
form.ShowInTaskbar = false;
form.BackColor = Color.Red;
NativeMethods.ShowWindow(form.Handle, (int)WindowShowStyle.ShowNormalNoActivate);
NativeMethods.SetWindowPos(form.Handle, handle, windowRect.X, windowRect.Y, windowRect.Width, windowRect.Height, NativeMethods.SWP_NOACTIVATE);
Application.DoEvents();
redBGImage = Screenshot.CaptureRectangleNative(windowRect) as Bitmap;
}
}
return(HelpersLib.GraphicsHelper.Core.RemoveCorners(windowImage, redBGImage));
}
return(null);
}
/// <summary>Captures a screenshot of a window using the Windows DWM</summary>
/// <param name="handle">handle of the window to capture</param>
/// <returns>the captured window image with or without cursor</returns>
public static Image CaptureWithDWM(Workflow wfdwm, IntPtr handle)
{
DebugHelper.WriteLine("Capturing with DWM");
Image windowImageDwm = null;
Bitmap redBGImage = null;
Rectangle windowRect = CaptureHelpers.GetWindowRectangle(handle);
if (windowRect.Width == 0)
{
System.Threading.Thread.Sleep(250);
windowRect = CaptureHelpers.GetWindowRectangle(handle); // try again
}
if (windowRect.Width > 0 && NativeMethods.IsDWMEnabled())
{
if (wfdwm.ActiveWindowDwmUseCustomBackground)
{
windowImageDwm = CaptureWindowWithDWM(handle, windowRect, out redBGImage, wfdwm.ActiveWindowDwmBackColor);
}
else if (wfdwm.ActiveWindowClearBackground)
{
windowImageDwm = CaptureWindowWithDWM(handle, windowRect, out redBGImage, Color.White);
}
}
if (windowImageDwm == null)
{
DebugHelper.WriteLine("Standard capture (no transparency)");
windowImageDwm = Screenshot.CaptureRectangleNative(windowRect);
}
Image result = RemoveCorners(handle, windowImageDwm, redBGImage, windowRect);
if (result != null)
{
windowImageDwm = result;
}
if (wfdwm.ActiveWindowIncludeShadows)
{
// Draw shadow manually to be able to have shadows in every case
windowImageDwm = HelpersLib.GraphicsHelper.Core.AddBorderShadow((Bitmap)windowImageDwm, true);
if (wfdwm.DrawCursor)
{
Point shadowOffset = HelpersLib.GraphicsHelper.Core.ShadowOffset;
#if DEBUG
DebugHelper.WriteLine("Fixed cursor position (before): " + windowRect.ToString());
#endif
windowRect.X -= shadowOffset.X;
windowRect.Y -= shadowOffset.Y;
#if DEBUG
DebugHelper.WriteLine("Fixed cursor position (after): " + windowRect.ToString());
#endif
}
}
if (wfdwm.DrawCursor)
{
CaptureHelpers.DrawCursorToImage(windowImageDwm, windowRect.Location);
}
return(windowImageDwm);
}
/// <summary>
/// Make a full-size thumbnail of the captured window on a new topmost form, and capture
/// this new form with a black and then white background. Then compute the transparency by
/// difference between the black and white versions.
/// This method has these advantages:
/// - the full form is captured even if it is obscured on the Windows desktop
/// - there is no problem with unpredictable Z-order anymore (the background and
/// the window to capture are drawn on the same window)
/// </summary>
/// <param name="handle">handle of the window to capture</param>
/// <param name="windowRect">the bounds of the window</param>
/// <param name="redBGImage">the window captured with a red background</param>
/// <param name="captureRedBGImage">whether to do the capture of the window with a red background</param>
/// <returns>the captured window image</returns>
private static Image CaptureWindowWithDWM(IntPtr handle, Rectangle windowRect, out Bitmap redBGImage, Color backColor)
{
Image windowImage = null;
redBGImage = null;
if (backColor != Color.White)
{
backColor = Color.FromArgb(255, backColor.R, backColor.G, backColor.B);
}
using (Form form = new Form())
{
form.StartPosition = FormStartPosition.Manual;
form.FormBorderStyle = FormBorderStyle.None;
form.ShowInTaskbar = false;
form.BackColor = backColor;
form.TopMost = true;
form.Bounds = CaptureHelpers.GetWindowRectangle(handle, false);
IntPtr thumb;
NativeMethods.DwmRegisterThumbnail(form.Handle, handle, out thumb);
SIZE size;
NativeMethods.DwmQueryThumbnailSourceSize(thumb, out size);
#if DEBUG
DebugHelper.WriteLine("Rectangle Size: " + windowRect.ToString());
DebugHelper.WriteLine("Window Size: " + size.ToString());
#endif
if (size.Width <= 0 || size.Height <= 0)
{
return(null);
}
DWM_THUMBNAIL_PROPERTIES props = new DWM_THUMBNAIL_PROPERTIES();
props.dwFlags = NativeMethods.DWM_TNP_VISIBLE | NativeMethods.DWM_TNP_RECTDESTINATION | NativeMethods.DWM_TNP_OPACITY;
props.fVisible = true;
props.opacity = (byte)255;
props.rcDestination = new RECT(0, 0, size.Width, size.Height);
NativeMethods.DwmUpdateThumbnailProperties(thumb, ref props);
form.Show();
System.Threading.Thread.Sleep(250);
if (form.BackColor != Color.White)
{
// no need for transparency; user has requested custom background color
NativeMethods.ActivateWindowRepeat(form.Handle, 250);
windowImage = Screenshot.CaptureRectangleNative(windowRect) as Bitmap;
}
else if (form.BackColor == Color.White)
{
// transparent capture
NativeMethods.ActivateWindowRepeat(handle, 250);
Bitmap whiteBGImage = Screenshot.CaptureRectangleNative(windowRect) as Bitmap;
form.BackColor = Color.Black;
form.Refresh();
NativeMethods.ActivateWindowRepeat(handle, 250);
Bitmap blackBGImage = Screenshot.CaptureRectangleNative(windowRect) as Bitmap;
// Capture rounded corners with except for Windows 8
if (ZAppHelper.IsWindows8())
{
form.BackColor = Color.Red;
form.Refresh();
NativeMethods.ActivateWindowRepeat(handle, 250);
redBGImage = Screenshot.CaptureRectangleNative(windowRect) as Bitmap;
}
form.BackColor = Color.White;
form.Refresh();
NativeMethods.ActivateWindowRepeat(handle, 250);
Bitmap whiteBGImage2 = Screenshot.CaptureRectangleNative(windowRect) as Bitmap;
// Don't do transparency calculation if an animated picture is detected
if (whiteBGImage.AreBitmapsEqual(whiteBGImage2))
{
windowImage = HelpersLib.GraphicsHelper.Core.ComputeOriginal(whiteBGImage, blackBGImage);
}
else
{
DebugHelper.WriteLine("Detected animated image => cannot compute transparency");
form.Close();
Application.DoEvents();
Image result = new Bitmap(whiteBGImage.Width, whiteBGImage.Height, PixelFormat.Format32bppArgb);
using (Graphics g = Graphics.FromImage(result))
{
// Redraw the image on a black background to avoid transparent pixels artifacts
g.Clear(Color.Black);
g.DrawImage(whiteBGImage, 0, 0);
}
windowImage = result;
}
blackBGImage.Dispose();
whiteBGImage.Dispose();
whiteBGImage2.Dispose();
}
NativeMethods.DwmUnregisterThumbnail(thumb);
}
return(windowImage);
}
