public static Bitmap RoundCorners(Bitmap StartImage, int cornerRadius, Brush backgroundColor) {
if (cornerRadius == 0) {
Bitmap roundedImage = new Bitmap(StartImage.Width, StartImage.Height);
var r = new Rectangle(0, 0, StartImage.Width - 2, StartImage.Height - 2);
using (Graphics g = Graphics.FromImage(roundedImage)) {
g.SmoothingMode = SmoothingMode.AntiAlias;
//g.CompositingQuality = CompositingQuality.HighQuality;
g.InterpolationMode = InterpolationMode.NearestNeighbor;
g.FillRectangle(backgroundColor, r);
g.DrawRectangle(Pens.Gray, r);
return roundedImage;
}
}
else {
var d = cornerRadius * 2;
Bitmap roundedImage = new Bitmap(StartImage.Width, StartImage.Height);
var r = new Rectangle(0, 0, StartImage.Width - d, StartImage.Height - d);
using (Graphics g = Graphics.FromImage(roundedImage)) {
g.SmoothingMode = SmoothingMode.AntiAlias;
//g.CompositingQuality = CompositingQuality.HighQuality;
g.InterpolationMode = InterpolationMode.NearestNeighbor;
System.Drawing.Drawing2D.GraphicsPath gp =
new System.Drawing.Drawing2D.GraphicsPath();
gp.AddArc(r.X, r.Y, d, d, 180, 90);
gp.AddArc(r.X + r.Width - d, r.Y, d, d, 270, 90);
gp.AddArc(r.X + r.Width - d, r.Y + r.Height - d, d, d, 0, 90);
gp.AddArc(r.X, r.Y + r.Height - d, d, d, 90, 90);
gp.AddLine(r.X, r.Y + r.Height - d, r.X, r.Y + d / 2);
g.FillPath(backgroundColor, gp);
g.DrawPath(Pens.Gray, gp);
return roundedImage;
}
}
}
}
