internal static byte[] GetCaptcha(string captchaText)
{
byte[] imageBytes = null;
int image2d_x = 0;
int image2d_y = 0;
SKRect size;
int compensateDeepCharacters = 0;
using (SKPaint drawStyle = CreatePaint())
{
compensateDeepCharacters = (int)drawStyle.TextSize / 5;
if (System.StringComparer.Ordinal.Equals(captchaText, captchaText.ToUpperInvariant()))
{
compensateDeepCharacters = 0;
}
size = SkiaHelpers.MeasureText(captchaText, drawStyle);
image2d_x = (int)size.Width + 10;
image2d_y = (int)size.Height + 10 + compensateDeepCharacters;
}
using (SKBitmap image2d = new SKBitmap(image2d_x, image2d_y, SKColorType.Bgra8888, SKAlphaType.Premul))
{
using (SKCanvas canvas = new SKCanvas(image2d))
{
canvas.DrawColor(SKColors.Black); // Clear
using (SKPaint drawStyle = CreatePaint())
{
canvas.DrawText(captchaText, 0 + 5, image2d_y - 5 - compensateDeepCharacters, drawStyle);
}
using (SKImage img = SKImage.FromBitmap(image2d))
{
using (SKData p = img.Encode(SKEncodedImageFormat.Png, 100))
{
imageBytes = p.ToArray();
}
}
}
}
return(imageBytes);
}
internal static byte[] GetCaptcha(string captchaText)
{
byte[] imageBytes = null;
// captchaText = @"你好";
// captchaText = @"你好，世界";
// captchaText = "ABC123";
// captchaText = "GOOSON";
captchaText = @"";
captchaText = @"Как дела ?";
captchaText = @"Hi Саша ;)";
//captchaText = captchaText.ToUpperInvariant();
System.Console.WriteLine(captchaText);
double[][] coord = null;
int image2d_x = 0;
int image2d_y = 0;
double bevel = 3;
// Calculate projection matrix
double[] T = MathHelpers.cameraTransform(
// new double[] { 0, -200, 250 },
new double[] { MathHelpers.rand(-90, 90), -200, MathHelpers.rand(150, 250) },
new double[] { 0, 0, 0 }
);
T = MathHelpers.matrixProduct(
T,
MathHelpers.viewingTransform(60, 300, 3000)
//MathHelpers.viewingTransform(15, 30, 3000)
);
SKRect size;
int compensateDeepCharacters = 0;
using (SKPaint drawStyle = CreatePaint())
{
compensateDeepCharacters = (int)drawStyle.TextSize / 5;
if (System.StringComparer.Ordinal.Equals(captchaText, captchaText.ToUpperInvariant()))
{
compensateDeepCharacters = 0;
}
size = SkiaHelpers.MeasureText(captchaText, drawStyle);
image2d_x = (int)size.Width + 10; // 10 = 2 * 5px
image2d_y = (int)size.Height + 10 + compensateDeepCharacters;
}
// SKImageInfo nfo = new SKImageInfo();
// SKBitmap bmp = new SKBitmap(300, 300, SKColorType.Rgba8888, SKAlphaType.Opaque);
using (SKBitmap image2d = new SKBitmap(image2d_x, image2d_y, SKColorType.Bgra8888, SKAlphaType.Premul))
{
using (SKCanvas canvas = new SKCanvas(image2d))
{
canvas.DrawColor(SKColors.Black); // Clear
using (SKPaint drawStyle = CreatePaint())
{
canvas.DrawText(captchaText, 0 + 5, image2d_y - 5 - compensateDeepCharacters, drawStyle);
}
} // End Using canvas
coord = new double[image2d_x * image2d_y][]; // { image2d_x * image2d_y };
// Calculate coordinates
int count = 0;
for (int y = 0; y < image2d_y; y += 2)
{
for (int x = 0; x < image2d_x; x++)
{
// Calculate x1, y1, x2, y2
double xc = x - image2d_x / 2.0;
double zc = y - image2d_y / 2.0;
double yc = -(SkiaHelpers.SkToArgb(image2d.GetPixel(x, y)) & 0xff) / 256.0 * bevel;
double[] xyz = new double[] { xc, yc, zc, 1 };
xyz = MathHelpers.vectorProduct(xyz, T);
coord[count] = xyz;
count++;
} // Next x
} // Next y
} // End Using image2d
// ----------------------------------------------------------------------
// Create 3d image
int image3d_x = (int)(400 * 1.5);
//image3d_y = image3d_x / 1.618;
int image3d_y = image3d_x * 9 / 16;
// image3d_x = 256 * 4;
// image3d_y = (int)(image3d_x * 0.05);
using (SKBitmap image3d = new SKBitmap(image3d_x, image3d_y, SKColorType.Bgra8888, SKAlphaType.Premul))
{
using (SKCanvas canvas = new SKCanvas(image3d))
{
// canvas.DrawColor(SKColors.Black); // Clear
// canvas.DrawColor(SKColors.Transparent); // Clear
canvas.DrawColor(SKColors.White); // Clear
// g.FillRectangle(hatchBrush, rect);
int count = 0;
double scale = 1.75 - image2d_x / 400.0;
for (int y = 0; y < image2d_y; y++)
{
for (int x = 0; x < image2d_x; x++)
{
if (x > 0)
{
if (coord[count - 1] == null)
{
continue;
}
double x0 = coord[count - 1][0] * scale + image3d_x / 2.0;
double y0 = coord[count - 1][1] * scale + image3d_y / 2.0;
double x1 = coord[count][0] * scale + image3d_x / 2.0;
double y1 = coord[count][1] * scale + image3d_y / 2.0;
using (SKPaint lineStyle = CreateLinePaint())
{
canvas.DrawLine((float)x0, (float)y0, (float)x1, (float)y1, lineStyle);
} // End Using lineStyle
} // End if (x > 0)
count++;
} // Next x
} // Next y
} // End Using canvas
using (SKImage img = SKImage.FromBitmap(image3d))
{
using (SKData p = img.Encode(SKImageEncodeFormat.Png, 100))
{
// p.SaveTo(strm);
imageBytes = p.ToArray();
} // End Using p
} // End Using img
} // End Using image3d
return(imageBytes);
} // End Function GetCaptcha
