/// <summary>
///
/// </summary>
/// <param name="width"></param>
/// <param name="height"></param>
/// <param name="angle"></param>
/// <returns></returns>
/// <remarks>
/// Code and logic from http://www.codeproject.com/KB/custom-controls/RotatedTextImageControl.aspx
/// </remarks>
protected RotationSize CalculateRotationSize(int width, int height, int angle)
{
int verticalOffset, horizontalOffset;
int rotatedHeight, rotatedWidth;
// convert the rotation angle to radians
double radians = ((double)angle / 180) * Math.PI;
// work out what the transalation offsets will need to be once the text is rotated
// to make sure the containning rectangle fits on completely on the image
if (angle <= 90)
{
verticalOffset = 0;
horizontalOffset = (int)Math.Abs(Math.Ceiling((double)height * Math.Sin(radians)));
}
else if (angle <= 180)
{
horizontalOffset = (int)Math.Ceiling(Math.Abs(width * Math.Sin(radians - (Math.PI / 2))) + Math.Abs(height * Math.Cos(radians - (Math.PI / 2))));
verticalOffset = (int)Math.Ceiling(Math.Abs(height * Math.Sin(radians - (Math.PI / 2))));
}
else if (angle <= 270)
{
verticalOffset = (int)Math.Ceiling(Math.Abs(width * Math.Sin(radians - (Math.PI))) + Math.Abs(height * Math.Cos(radians - (Math.PI))));
horizontalOffset = (int)Math.Ceiling(Math.Abs(width * Math.Cos(radians - (Math.PI))));
}
else
{
verticalOffset = (int)Math.Ceiling(Math.Abs(width * Math.Cos(radians - (Math.PI * 1.5))));
horizontalOffset = 0;
}
// work out the size of the containing rectangle
rotatedHeight = (int)Math.Ceiling(Math.Abs(height * Math.Cos(radians)) + (Math.Abs(width * Math.Sin(radians))));
rotatedWidth = (int)Math.Ceiling(Math.Abs(width * Math.Cos(radians)) + (Math.Abs(height * Math.Sin(radians))));
RotationSize rs = new RotationSize()
{
VerticalOffset = verticalOffset,
HorizontalOffset = horizontalOffset,
RotatedWidth = rotatedWidth,
RotatedHeight = rotatedHeight
};
return(rs);
}
// TODO examine to add text to a transparent GIF image still works.
public override Image ProcessImage(Image input, ProjectSetting ps)
{
try {
if (ps.WatermarkCollection.Count < watermarkIndex)
{
return(input);
}
WatermarkText wt = ps.WatermarkCollection[this.watermarkIndex] as WatermarkText;
if (wt == null)
{
return(input);
}
#if DEBUG
Debug.WriteLine("Current Thread: "
+ Thread.CurrentThread.ManagedThreadId + ","
+ " Image File Name: " + this.ImageFileName + ","
+ " Watermark Text index: " + watermarkIndex);
#endif
int iHOffset = 0;
int iVOffset = 0;
int rotatedTextHeight = 0;
int rotatedTextWidth = 0;
int iBmpHeight = 0;
int iBmpWidth = 0;
float fHRes = 0;
float fVRes = 0;
int textWidth = 0;
int textHeight = 0;
int xAfterOffset = 0;
int yAfterOffset = 0;
string textToDraw = wt.Text;
List <ExifContainerItem> tagsFound = this.FindExifTags(textToDraw);
if (tagsFound != null && tagsFound.Count > 0 && !string.IsNullOrEmpty(this.ImageFileName))
{
// at least one Exif tag is found
textToDraw = ConvertExifTagsToText(textToDraw, tagsFound);
}
textToDraw = this.ConvertControlTagsToText(textToDraw);
// create a bitmap we can use to work out the size of the text,
// we will then create a new bitmap that is the right size.
// we also use this to record the default resolution
Bitmap bmp = new Bitmap(1, 1, PixelFormat.Format32bppArgb);
fHRes = bmp.HorizontalResolution;
fVRes = bmp.VerticalResolution;
Graphics g = Graphics.FromImage(bmp);
StringFormat format = new StringFormat();
format.Alignment = wt.WatermarkTextAlignment;
SizeF sf = g.MeasureString(textToDraw, wt.WatermarkTextFont,
Int32.MaxValue, format);
g.Dispose();
bmp.Dispose();
// get the width and height of the text
textWidth = Math.Max(2, (int)Math.Ceiling(sf.Width));
textHeight = Math.Max(2, (int)Math.Ceiling(sf.Height));
RotationSize rs = CalculateRotationSize(textWidth, textHeight, wt.WatermarkRotateAngle);
iHOffset = rs.HorizontalOffset;
iVOffset = rs.VerticalOffset;
rotatedTextWidth = rs.RotatedWidth;
rotatedTextHeight = rs.RotatedHeight;
bmp = new Bitmap(input);
iBmpWidth = bmp.Width;
iBmpHeight = bmp.Height;
g = Graphics.FromImage(bmp);
// determine the offset needed to position the text in the right place
// in the background if it is not the same size as we calculate was needed for the text
// adding in the padding where necessary and
// remembering to adjust for differences in padding between left/right top/bottom etc.
switch (wt.WatermarkPosition)
{
case ContentAlignment.TopLeft:
case ContentAlignment.TopCenter:
case ContentAlignment.TopRight:
//yAfterOffset = definition.TextPadding.Top;
yAfterOffset = wt.Padding;
break;
case ContentAlignment.MiddleLeft:
case ContentAlignment.MiddleCenter:
case ContentAlignment.MiddleRight:
//yAfterOffset = (bmp.Height - rotatedHeight) / 2 + definition.TextPadding.Top - definition.TextPadding.Bottom;
yAfterOffset = (bmp.Height - rotatedTextHeight) / 2 + wt.Padding - wt.Padding;
break;
case ContentAlignment.BottomLeft:
case ContentAlignment.BottomCenter:
case ContentAlignment.BottomRight:
//yAfterOffset = (bmp.Height - rotatedHeight) - definition.TextPadding.Bottom;
yAfterOffset = (bmp.Height - rotatedTextHeight) - wt.Padding;
break;
}
switch (wt.WatermarkPosition)
{
case ContentAlignment.TopLeft:
case ContentAlignment.MiddleLeft:
case ContentAlignment.BottomLeft:
//xAfterOffset = definition.TextPadding.Left;
xAfterOffset = wt.Padding;
break;
case ContentAlignment.TopCenter:
case ContentAlignment.MiddleCenter:
case ContentAlignment.BottomCenter:
//xAfterOffset = (bmp.Width - rotatedWidth) / 2 + definition.TextPadding.Left - definition.TextPadding.Right;
xAfterOffset = (bmp.Width - rotatedTextWidth) / 2 + wt.Padding - wt.Padding;
break;
case ContentAlignment.TopRight:
case ContentAlignment.MiddleRight:
case ContentAlignment.BottomRight:
//xAfterOffset = (bmp.Width - rotatedWidth) - definition.TextPadding.Right;
xAfterOffset = (bmp.Width - rotatedTextWidth) - wt.Padding;
break;
}
// create a new transformation matrix to do the rotation and corresponding translation
Matrix matrix = new Matrix();
// translation to position the text as required by HAlignment and VAlignment
matrix.Translate(xAfterOffset, yAfterOffset);
// translation to bring the rotation back to view
matrix.Translate(iHOffset, iVOffset);
// transformation to rotate the text
matrix.Rotate(wt.WatermarkRotateAngle);
if (wt.WatermarkTextAlignment == StringAlignment.Center)
{
// transformation to cope with non left aligned text
matrix.Translate(textWidth / 2, 0);
}
else if (wt.WatermarkTextAlignment == StringAlignment.Far)
{
matrix.Translate(textWidth, 0);
}
// apply the transformation to the graphics object and write out the text
g.Transform = matrix;
g.SmoothingMode = SmoothingMode.HighQuality;
g.TextRenderingHint = TextRenderingHint.AntiAlias;
// draw a shadow with semi transparent black
g.DrawString(textToDraw,
wt.WatermarkTextFont,
new SolidBrush(Color.FromArgb(153, 0, 0, 0)), 1, 1, format);
// draw the sctual text
g.DrawString(textToDraw,
wt.WatermarkTextFont,
new SolidBrush(wt.WatermarkTextColor), 0, 0, format);
g.Transform = matrix;
g.Dispose();
return(bmp);
} catch (Exception ex) {
Trace.TraceError(ex.ToString());
return(input);
}
}