public void SelectBitmap(Bitmap bitmap, int opacity)
{
if (bitmap.PixelFormat != PixelFormat.Format32bppArgb)
{
throw new ApplicationException("The bitmap must be 32bpp with alpha-channel.");
}
IntPtr screenDc = NativeMethods.GetDC(IntPtr.Zero);
IntPtr memDc = NativeMethods.CreateCompatibleDC(screenDc);
IntPtr hBitmap = IntPtr.Zero;
IntPtr hOldBitmap = IntPtr.Zero;
try
{
hBitmap = bitmap.GetHbitmap(Color.FromArgb(0));
hOldBitmap = NativeMethods.SelectObject(memDc, hBitmap);
SIZE newSize = new SIZE(bitmap.Width, bitmap.Height);
POINT sourceLocation = new POINT(0, 0);
POINT newLocation = new POINT(this.Left, this.Top);
BLENDFUNCTION blend = new BLENDFUNCTION();
blend.BlendOp = NativeMethods.AC_SRC_OVER;
blend.BlendFlags = 0;
blend.SourceConstantAlpha = (byte)opacity;
blend.AlphaFormat = NativeMethods.AC_SRC_ALPHA;
NativeMethods.UpdateLayeredWindow(this.Handle, screenDc, ref newLocation, ref newSize, memDc, ref sourceLocation, 0, ref blend, NativeMethods.ULW_ALPHA);
}
finally
{
NativeMethods.ReleaseDC(IntPtr.Zero, screenDc);
if (hBitmap != IntPtr.Zero)
{
NativeMethods.SelectObject(memDc, hOldBitmap);
NativeMethods.DeleteObject(hBitmap);
}
NativeMethods.DeleteDC(memDc);
}
}
public static MyCursor CaptureCursor()
{
CursorInfo cursorInfo = new CursorInfo();
cursorInfo.cbSize = Marshal.SizeOf(cursorInfo);
if (GetCursorInfo(out cursorInfo) && cursorInfo.flags == CURSOR_SHOWING)
{
cursorInfo.ptScreenPos = CaptureHelpers.GetZeroBasedMousePosition();
IntPtr hicon = CopyIcon(cursorInfo.hCursor);
if (hicon != IntPtr.Zero)
{
IconInfo iconInfo;
if (GetIconInfo(hicon, out iconInfo))
{
Point position = new Point(cursorInfo.ptScreenPos.X - iconInfo.xHotspot, cursorInfo.ptScreenPos.Y - iconInfo.yHotspot);
using (Bitmap maskBitmap = Bitmap.FromHbitmap(iconInfo.hbmMask))
{
Bitmap resultBitmap = null;
if (IsCursorMonochrome(maskBitmap))
{
resultBitmap = new Bitmap(maskBitmap.Width, maskBitmap.Width);
Graphics desktopGraphics = Graphics.FromHwnd(GetDesktopWindow());
IntPtr desktopHdc = desktopGraphics.GetHdc();
IntPtr maskHdc = NativeMethods.CreateCompatibleDC(desktopHdc);
IntPtr oldPtr = NativeMethods.SelectObject(maskHdc, maskBitmap.GetHbitmap());
using (Graphics resultGraphics = Graphics.FromImage(resultBitmap))
{
IntPtr resultHdc = resultGraphics.GetHdc();
// These two operation will result in a black cursor over a white background.
// Later in the code, a call to MakeTransparent() will get rid of the white background.
NativeMethods.BitBlt(resultHdc, 0, 0, 32, 32, maskHdc, 0, 32, CopyPixelOperation.SourceCopy);
NativeMethods.BitBlt(resultHdc, 0, 0, 32, 32, maskHdc, 0, 0, CopyPixelOperation.SourceInvert);
resultGraphics.ReleaseHdc(resultHdc);
}
IntPtr newPtr = NativeMethods.SelectObject(maskHdc, oldPtr);
NativeMethods.DeleteDC(newPtr);
NativeMethods.DeleteDC(maskHdc);
desktopGraphics.ReleaseHdc(desktopHdc);
// Remove the white background from the BitBlt calls,
// resulting in a black cursor over a transparent background.
resultBitmap.MakeTransparent(Color.White);
}
else
{
resultBitmap = Icon.FromHandle(hicon).ToBitmap();
}
return(new MyCursor(new Cursor(cursorInfo.hCursor), position, resultBitmap));
}
}
}
}
return(new MyCursor());
}
