private void GenerateBordersPaths(Bitmap bitmap)
{
Rectangle rect = new Rectangle(0, 0, bitmap.Width, bitmap.Height);
BitmapData bmpData = bitmap.LockBits(rect, ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
IntPtr ptr = bmpData.Scan0;
int bytes = bmpData.Stride * bitmap.Height;
byte[] rgbValues = new byte[bytes];
Marshal.Copy(ptr, rgbValues, 0, bytes);
int height = bitmap.Height;
int width = bitmap.Width;
Color[,] pixelColors = new Color[bitmap.Height, bitmap.Width];
// Store pixel color in matrix
Parallel.For(0, bytes / 3, (int i) =>
{
i *= 3;
int pRow = (i / 3) / width;
int pCol = (i / 3) % width;
pixelColors[pRow, pCol] = Color.FromArgb(rgbValues[i + 2], rgbValues[i + 1], rgbValues[i]);
});
bitmap.UnlockBits(bmpData);
// Stores vertical and horizontal border pixels of a province
Dictionary <Color, HashSet <BorderPoint[]> > provincesPoints = new Dictionary <Color, HashSet <BorderPoint[]> >(this._mProvinceCount);
object lockObj = new Object();
//Traverse lines
Parallel.For(0, height, (int prow) =>
{
for (int col = 0; col < width; col++)
{
Color color = pixelColors[prow, col];
lock (lockObj)
{
if (!provincesPoints.ContainsKey(color))
{
provincesPoints.Add(color, new HashSet <BorderPoint[]>());
}
}
BorderPoint[] colorLine = new BorderPoint[3];
colorLine[0] = new BorderPoint(col, prow);
do
{
if (col < width)
{
if (color == pixelColors[prow, col])
{
col++;
}
else
{
break;
}
}
else
{
break;
}
} while (true);
col--;
colorLine[1] = new BorderPoint(col, prow);
colorLine[2] = new BorderPoint(-1, 0); // horizontal line
lock (lockObj)
{
HashSet <BorderPoint[]> lines = provincesPoints[color];
lines.Add(colorLine);
}
}
});
//Traverse columns
Parallel.For(0, width, (int col) =>
{
for (int row = 0; row < height; row++)
{
Color color = pixelColors[row, col];
BorderPoint[] colorLine = new BorderPoint[3];
colorLine[0] = new BorderPoint(col, row);
do
{
if (row < height)
{
if (color == pixelColors[row, col])
{
row++;
}
else
{
break;
}
}
else
{
break;
}
} while (true);
row--;
colorLine[1] = new BorderPoint(col, row);
colorLine[2] = new BorderPoint(-2, 0); // vertical line
lock (lockObj)
{
HashSet <BorderPoint[]> lines = provincesPoints[color];
lines.Add(colorLine);
}
}
});
this._mProvincesLines = new Dictionary <Color, HashSet <BorderLine> >(provincesPoints.Count);
// Get border lines from border pixels
object lockobj = new Object();
Parallel.ForEach(provincesPoints, (KeyValuePair <Color, HashSet <BorderPoint[]> > keyValue) =>
{
lock (lockobj)
{
this._mProvincesLines.Add(keyValue.Key, new HashSet <BorderLine>(keyValue.Value.Count / 4));
}
this.ProcessProvince(keyValue.Value, this._mProvincesLines[keyValue.Key]);
});
}
/// <summary>
/// Initialize a new instance of <see cref="BorderLine"/> that has the specified coordinates.
/// </summary>
/// <param name="start"> Start of the line.</param>
/// <param name="end"> End of the line.</param>
public BorderLine(BorderPoint start, BorderPoint end)
{
this._mStart = start;
this._mEnd = end;
}