private static void SaveDebugImage(DirectBitmap db, CoordsData coordsData, int nr)
{
using (var bmp = db.Bitmap.Clone(new Rectangle(0, 0, db.Width, db.Height), db.Bitmap.PixelFormat))
{
var setCoordsCount = coordsData.Coords.Count;
var step = 255 / setCoordsCount;
using (var g = Graphics.FromImage(bmp))
{
using (var b = new SolidBrush(Color.Black))
for (int c = 0; c < setCoordsCount; c++)
{
b.Color = Color.FromArgb(255 - (c * step), c * step, 50);
g.FillRectangle(b, new Rectangle(coordsData.Coords[c].X, coordsData.Coords[c].Y, 1, 1));
}
const int factor = 5;
using (var resizedBmp = new Bitmap(bmp.Width * factor, bmp.Height * factor))
using (var gr = Graphics.FromImage(resizedBmp))
{
gr.DrawImage(bmp, new Rectangle(0, 0, bmp.Width * factor, bmp.Height * factor));
resizedBmp.Save(Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop),
"ASBFontTesting", "RegionGrowing", $"RG_{DateTime.Now:yyyy-MM-dd-HH-mm-ss-ffff}_{nr}.png"));
}
}
}
}
private static CoordsData VisitChar(int x, int y, bool[,] visited, DirectBitmap db, CoordsData data = null)
{
// TODO better region growing algorithm?
if (data == null)
{
data = new CoordsData(x, x, y, y);
}
data.Add(x, y);
for (int i = 0; i < OffsetX.Length; i++)
{
var nextX = OffsetX[i] + x;
var nextY = OffsetY[i] + y;
var isSafe = nextX > 0 && nextX < db.Width && nextY > 0 && nextY < db.Height && !visited[nextX, nextY];
if (!isSafe)
{
continue;
}
visited[nextX, nextY] = true;
if (IsNotBlank(db, nextX, nextY))
{
VisitChar(nextX, nextY, visited, db, data);
}
}
return(data);
}
private static void VisitVertical(CoordsData coordsData, bool[,] visited, DirectBitmap db)
{
for (int i = coordsData.MinX; i <= coordsData.MaxX; i++)
{
for (int j = 0; j < db.Height; j++)
{
if (!visited[i, j] && IsNotBlank(db, i, j))
{
coordsData.Add(i, j);
}
visited[i, j] = true;
}
}
}
/// <summary>
/// Adds set pixels of all columns of the pattern that are not part of another pattern.
/// </summary>
private static void VisitVertical(CoordsData coordsData, bool[,] visited, bool[,] image)
{
var h = image.GetLength(1);
for (int x = coordsData.MinX; x <= coordsData.MaxX; x++)
{
for (int y = 0; y < h; y++)
{
if (visited[x, y])
{
continue;
}
if (image[x, y])
{
VisitChar(x, y, visited, image, coordsData);
}
visited[x, y] = true;
}
}
}
///// <summary>
///// Collect all neighboring pixels of a character (region growing with recursive calls).
///// </summary>
//private static CoordsData VisitCharRecursively(int x, int y, bool[,] visited, bool[,] image, CoordsData data = null)
//{
// if (data == null)
// data = new CoordsData(x, x, y, y);
// var w = image.GetLength(0);
// var h = image.GetLength(1);
// data.Add(x, y);
// for (int i = 0; i < OffsetX.Length; i++)
// {
// var nextX = OffsetX[i] + x;
// var nextY = OffsetY[i] + y;
// var isSafe = nextX >= 0 && nextX < w && nextY >= 0 && nextY < h && !visited[nextX, nextY];
// if (!isSafe)
// {
// continue;
// }
// visited[nextX, nextY] = true;
// if (image[nextX, nextY])
// {
// VisitCharRecursively(nextX, nextY, visited, image, data);
// }
// }
// // debug
// //data.ToDebugConsole();
// return data;
//}
/// <summary>
/// Collect all neighboring pixels of a character (region growing with a stack).
/// </summary>
private static CoordsData VisitChar(int x, int y, bool[,] visited, bool[,] image, CoordsData data = null)
{
if (data == null)
{
data = new CoordsData(x, x, y, y);
}
var w = image.GetLength(0);
var h = image.GetLength(1);
var stackToCheck = new Stack <(int x, int y)>(image.GetLength(1) * 2);
stackToCheck.Push((-1, -1));
stackToCheck.Push((x, y));
do
{
var(cx, cy) = stackToCheck.Pop();
data.Add(cx, cy);
visited[cx, cy] = true;
for (int i = 0; i < OffsetX.Length; i++)
{
var nextX = OffsetX[i] + cx;
var nextY = OffsetY[i] + cy;
// add neighbors that are set
if (nextX >= 0 && nextX < w && nextY >= 0 && nextY < h &&
!visited[nextX, nextY] &&
image[nextX, nextY])
{
visited[nextX, nextY] = true;
stackToCheck.Push((nextX, nextY));
}
}
}while (stackToCheck.Peek().x != -1);
return(data);
}
