public static string Generate(Graphics graphics, Bitmap bitmap, Font font, HashSet<char> char_set)
{
Size char_size = GetCharSize(font);
var dict_char = new Dictionary<char, int>();
int min_char = int.MaxValue, max_char = int.MinValue;
using (Bitmap char_bitmap = new Bitmap(char_size.Width, char_size.Height))
{
using (Graphics char_graphics = Graphics.FromImage(char_bitmap))
{
foreach (var ch in char_set)
{
char_graphics.Clear(Color.White);
char_graphics.DrawString(ch.ToString(), font, black_brush, 0.0f, 0.0f);
int sum = 0;
for (int i = 0; i < char_bitmap.Width; i++)
{
for (int j = 0; j < char_bitmap.Height; j++)
{
Color color = char_bitmap.GetPixel(i, j);
sum += color.R + color.G + color.B;
}
}
dict_char[ch] = sum;
if (sum < min_char)
{
min_char = sum;
}
if (sum > max_char)
{
max_char = sum;
}
}
}
}
foreach (var key in char_set)
{
dict_char[key] -= min_char;
}
max_char -= min_char;
var dict_char_ordered = dict_char.OrderBy(kvp => kvp.Value);
var bitmap_matrix = new int[bitmap.Width, bitmap.Height];
int min_bitmap = int.MaxValue, max_bitmap = int.MinValue;
for (int i = 0; i < bitmap.Width; i++)
{
for (int j = 0; j < bitmap.Height; j++)
{
Color color = bitmap.GetPixel(i, j);
int sum = color.A * (color.R + color.G + color.B) + (255 - color.A) * 765;
bitmap_matrix[i, j] = sum;
if (sum < min_bitmap)
{
min_bitmap = sum;
}
if (sum > max_bitmap)
{
max_bitmap = sum;
}
}
}
for (int i = 0; i < bitmap.Width; i++)
{
for (int j = 0; j < bitmap.Height; j++)
{
bitmap_matrix[i, j] -= min_bitmap;
}
}
max_bitmap -= min_bitmap;
Random random = new Random();
StringBuilder sb = new StringBuilder();
for (int j = 0; j < bitmap.Height; j++)
{
for (int i = 0; i < bitmap.Width; i++)
{
double position = (double)((long)bitmap_matrix[i, j] * max_char) / max_bitmap;
var kvp1 = dict_char_ordered.Last(kvp => kvp.Value <= position);
var kvp2 = dict_char_ordered.First(kvp => kvp.Value >= position);
if (kvp1.Value == kvp2.Value || random.NextDouble() >= (position - kvp1.Value) / (kvp2.Value - kvp1.Value))
{
sb.Append(kvp1.Key);
}
else
{
sb.Append(kvp2.Key);
}
}
sb.AppendLine();
}
return sb.ToString();
}
