public static Bitmap RotateImage(Image inputImg, double degreeAngle)
{
PointF[] pointF = new PointF[] { new PointF(0f, 0f), new PointF((float)inputImg.Width, 0f), new PointF(0f, (float)inputImg.Height), new PointF((float)inputImg.Width, (float)inputImg.Height) };
PointF[] rotationPoints = pointF;
PointMath.RotatePoints(rotationPoints, new PointF((float)inputImg.Width / 2f, (float)inputImg.Height / 2f), degreeAngle);
Rectangle bounds = PointMath.GetBounds(rotationPoints);
Bitmap rotatedBitmap = new Bitmap(bounds.Width, bounds.Height);
Graphics g = Graphics.FromImage(rotatedBitmap);
try
{
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
Matrix m = new Matrix();
m.RotateAt((float)degreeAngle, new PointF((float)inputImg.Width / 2f, (float)inputImg.Height / 2f));
m.Translate((float)(-bounds.Left), (float)(-bounds.Top), MatrixOrder.Append);
g.Transform = m;
g.DrawImage(inputImg, 0, 0);
}
finally
{
if (g != null)
{
((IDisposable)g).Dispose();
}
}
return(rotatedBitmap);
}
public static void RotatePoints(PointF[] pnts, PointF origin, double degreeAngle)
{
for (int i = 0; i < (int)pnts.Length; i++)
{
pnts[i] = PointMath.RotatePoint(pnts[i], origin, degreeAngle);
}
}
public static Rectangle GetBounds(PointF[] pnts)
{
RectangleF boundsF = PointMath.GetBoundsF(pnts);
Rectangle rectangle = new Rectangle((int)Math.Round((double)boundsF.Left), (int)Math.Round((double)boundsF.Top), (int)Math.Round((double)boundsF.Width), (int)Math.Round((double)boundsF.Height));
return(rectangle);
}
public static PointF RotatePoint(PointF pnt, PointF origin, double degreeAngle)
{
double radAngle = PointMath.DegreeToRadian(degreeAngle);
PointF newPoint = new PointF();
double deltaX = (double)(pnt.X - origin.X);
double deltaY = (double)(pnt.Y - origin.Y);
newPoint.X = (float)((double)origin.X + (Math.Cos(radAngle) * deltaX - Math.Sin(radAngle) * deltaY));
newPoint.Y = (float)((double)origin.Y + (Math.Sin(radAngle) * deltaX + Math.Cos(radAngle) * deltaY));
return(newPoint);
}
public static PointF RotatePoint(PointF pnt, double degreeAngle)
{
PointF pointF = PointMath.RotatePoint(pnt, new PointF(0f, 0f), degreeAngle);
return(pointF);
}
