Create a semi-transparent cursor from an image

Answer 1

Could this not present a usability issue? It is unlikely your users will expect this behaviour.

Answer 2

On the top of my head (I would try that first):

1. create new bitmap with same size as original, but with ARGB structure
2. drawimage: existing bitmap to the new bitmap
3. access raw bitmap data, and replace A bytes with 128

You should have nice semitransparent bitmap there.

If performance allows, you can scan for fully transparent pixels and set A to zero for them!

Answer 3

I've tried following example, and it was working fine...

    public struct IconInfo
    {
        public bool fIcon;
        public int xHotspot;
        public int yHotspot;
        public IntPtr hbmMask;
        public IntPtr hbmColor;
    }

[DllImport("user32.dll")] [return: MarshalAs(UnmanagedType.Bool)] public static extern bool GetIconInfo(IntPtr hIcon, ref IconInfo pIconInfo);

[DllImport("user32.dll")] public static extern IntPtr CreateIconIndirect(ref IconInfo icon);

    public static Cursor CreateCursor(Bitmap bmp, int xHotSpot, int yHotSpot)
    {
        IntPtr ptr = bmp.GetHicon();
        IconInfo tmp = new IconInfo();
        GetIconInfo(ptr, ref tmp);
        tmp.xHotspot = xHotSpot;
        tmp.yHotspot = yHotSpot;
        tmp.fIcon = false;
        ptr = CreateIconIndirect(ref tmp);
        return new Cursor(ptr);
    }

And i've put this on button click event (you can call from where you like):

Bitmap b = new Bitmap("D:/Up.png"); this.Cursor = CreateCursor(b, 5, 5);

And the Up.png image is savd with 75% opacity in AdobePhotoshop.