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Maintaining Image/Bitmap Transparency through Graphics.Draw

Is there anyway of maintaining an images transparency/alpha channel for pngs when using System.Drawing.Graphics.DrawImage.

What I am basically doing is overlapping 4 or 5 images that all have transparency, but the transparency is being lost in the process, the code being used is shown below

System.Drawing.Image frmImg = System.Drawing.Bitmap.FromFile(framePath);
        System.Drawing.Graphics frame = System.Drawing.Graphics.FromImage(frmImg);
        frame.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
        frame.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
        
 
        // Setup the Shadow and Mount
        System.Drawing.Image shadow = System.Drawing.Bitmap.FromFile(shadowPath);
 
        // Draw the Picture
        System.Drawing.Image picture = System.Drawing.Bitmap.FromFile(MapPath(imgUrl));
        frame.DrawImage(picture, 44, 38, 260, 185);
 
        // If it has a mount then draw the mount
        if (hasMount)
        {
            System.Drawing.Image mountCore = System.Drawing.Bitmap.FromFile(mountCorePath);
            frame.DrawImage(mountCore, new System.Drawing.Point(0, 0));
        }
 
        // Draw Shadow
        frame.DrawImage(shadow, new System.Drawing.Point(0, 0));
        
        
 
        // Respond with a PNG image to the browser
        System.IO.MemoryStream ms = new System.IO.MemoryStream();
        frmImg.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
        Response.BinaryWrite(ms.GetBuffer());

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Melih SARICA

tr this

Dim myBitmap As New Bitmap("Grapes.gif")

' Draw myBitmap to the screen.
e.Graphics.DrawImage(myBitmap, 0, 0, myBitmap.Width, _
myBitmap.Height)

' Make the default transparent color transparent for myBitmap.
myBitmap.MakeTransparent() <--- this what u need

' Draw the transparent bitmap to the screen.
e.Graphics.DrawImage(myBitmap, myBitmap.Width, 0, myBitmap.Width, _
myBitmap.Height)

recruitit

ASKER

Actually I have a problem, there's parts of the image that are transparent, rather than sections of the image. Like as an example I might have a blue ball, and the background for the blue ball image is transparent, but the blue ball is also semi-transparent so that when I place it in a web browser you can see behind the blue ball. This is unfortionetly the part that is not being transferred over is the partial transparency.

ASKER CERTIFIED SOLUTION

Melih SARICA

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recruitit

ASKER

Ah ok, thanks for the correction. That is what I am looking for. :o)

recruitit

ASKER

I suppose I need to re-address the question then.

recruitit

ASKER

It was correct for the question being asked.