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c#winformstransparencymouse-cursor

Create a semi-transparent cursor from an image


Is it possible to create a cursor from an image and have it be semi-transparent?

I'm currently taking a custom image and overylaying the mouse cursor image. It would be great if I could make this semi-transparent, but not necessary. The sales guys love shiny.

Currently doing something like this:

Image cursorImage = customImage.GetThumbnailImage(300, 100, null, IntPtr.Zero);
cursorImage.SetResolution(96.0F, 96.0F);
int midPointX = cursorImage.Width / 2;
int midPointY = cursorImage.Height / 2;
Bitmap cursorMouse = GetCursorImage(cursorOverlay);
Graphics cursorGfx = Graphics.FromImage(cursorImageCopy);
cursorGfx.DrawImageUnscaled(cursorMouse, midPointX, midPointY);

Cursor tmp = new Cursor(cursorImage.GetHicon());

alt text http://members.cox.net/dustinbrooks/drag.jpg


Solution

  • 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 saved with 75% opacity in AdobePhotoshop.