/// <summary>
/// Draws the stroke of the specified data series points.
/// </summary>
/// <param name="dataSeries">The data series.</param>
/// <param name="points">The points.</param>
public void DrawSeries(WpfGraphDataSeries dataSeries, IEnumerable <System.Drawing.PointF> points)
{
_g.DrawCurve(dataSeries.GdiPen, points.ToArray());
}
///
/// makeCaptcha
///
public System.Drawing.Bitmap makeCaptcha()
{
System.Random randomGenerator = new System.Random();
System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(img_width, img_height
, System.Drawing.Imaging.PixelFormat.Format16bppRgb555);
System.Drawing.Rectangle rect = new System.Drawing.Rectangle(0, 0, img_width, img_height);
System.Drawing.StringFormat sFormat = new System.Drawing.StringFormat();
sFormat.Alignment = System.Drawing.StringAlignment.Center;
sFormat.LineAlignment = System.Drawing.StringAlignment.Center;
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bmp);
// Set up the text font.
System.Drawing.SizeF size;
float fontSize = img_fontsize + 1;
System.Drawing.Font font;
// try to use requested font, but
// If the named font is not installed, default to a system font.
try
{
font = new System.Drawing.Font(img_fontname, img_fontsize);
font.Dispose();
}
catch (System.Exception ex)
{
img_fontname = System.Drawing.FontFamily.GenericSerif.Name;
}
// build a new string with space through the chars
// i.e. keyword 'hello' become 'h e l l o '
string tempKey = "";
for (int ii = 0; ii < sKeyword.Length; ii++)
{
tempKey = string.Concat(tempKey, sKeyword[ii].ToString());
tempKey = string.Concat(tempKey, " ");
}
// Adjust the font size until the text fits within the image.
do
{
fontSize--;
font = new System.Drawing.Font(img_fontname, fontSize, img_fontstyle);
size = g.MeasureString(tempKey, font);
} while (size.Width > (0.8 * bmp.Width));
img_font = font;
g.Clear(System.Drawing.Color.Silver); // blank the image
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias; // antialias objects
// fill with a liner gradient
// random colors
g.FillRectangle(
new System.Drawing.Drawing2D.LinearGradientBrush(
new System.Drawing.Point(0, 0),
new System.Drawing.Point(bmp.Width, bmp.Height),
System.Drawing.Color.FromArgb(
255, //randomGenerator.Next(255),
randomGenerator.Next(255),
randomGenerator.Next(255),
randomGenerator.Next(255)
),
System.Drawing.Color.FromArgb(
randomGenerator.Next(100),
randomGenerator.Next(255),
randomGenerator.Next(255),
randomGenerator.Next(255)
)),
rect);
// apply swirl filter
if (fDegree == 0)
{
BitmapFilter.Swirl(bmp, randomGenerator.NextDouble(), true);
}
else
{
BitmapFilter.Swirl(bmp, fDegree, true);
}
// draw a first line crossing the image
// int y1, y2;
// y1 = randomGenerator.Next(bmp.Height/3) + (bmp.Height/3);
// y2 = bmp.Height - randomGenerator.Next(bmp.Height/3);
//
// g.DrawLine(new Pen( img_fontcolor, 2),
// new Point(0,y1), new Point(bmp.Width,y2));
// Add some random noise.
System.Drawing.Drawing2D.HatchBrush hatchBrush = new System.Drawing.Drawing2D.HatchBrush(
System.Drawing.Drawing2D.HatchStyle.LargeConfetti,
System.Drawing.Color.LightGray,
System.Drawing.Color.DarkGray);
int m = System.Math.Max(rect.Width, rect.Height);
for (int i = 0; i < (int)(rect.Width * rect.Height / 30F); i++)
{
int x = randomGenerator.Next(rect.Width);
int y = randomGenerator.Next(rect.Height);
int w = randomGenerator.Next(m / 50);
int h = randomGenerator.Next(m / 50);
g.FillEllipse(hatchBrush, x, y, w, h);
}
// write keyword
// keyword positioning
// to space equally
int posx;
int posy;
int deltax;
deltax = System.Convert.ToInt32(size.Width / tempKey.Length);
posx = System.Convert.ToInt32((img_width - size.Width) / 2);
// write each keyword char
for (int l = 0; l < tempKey.Length; l++)
{
posy = ((int)(2.5 * (bmp.Height / 5))) + (((l % 2) == 0)?-2:2) * ((int)(size.Height / 3));
posy = (int)((bmp.Height / 2) + (size.Height / 2));
posy += (int)((((l % 2) == 0)?-2:2) * ((size.Height / 3)));
posx += deltax;
g.DrawString(tempKey[l].ToString(),
img_font,
img_fontcolor,
posx,
posy,
sFormat);
}
// draw a curve
System.Drawing.Point[] ps = new System.Drawing.Point[nPoints];
for (int ii = 0; ii < nPoints; ii++)
{
int x, y;
x = randomGenerator.Next(bmp.Width);
y = randomGenerator.Next(bmp.Height);
ps[ii] = new System.Drawing.Point(x, y);
}
g.DrawCurve(new System.Drawing.Pen(img_fontcolor, 2), ps
, System.Convert.ToSingle(randomGenerator.NextDouble()));
// apply water filter
BitmapFilter.Water(bmp, nWave, false);
// Clean up.
font.Dispose();
hatchBrush.Dispose();
g.Dispose();
return(bmp);
}
