public void Import(CommandLineOptions options)
{
// Load the source bitmap.
Bitmap bitmap;
try
{
bitmap = new Bitmap(options.SourceFont);
}
catch
{
throw new Exception(string.Format("Unable to load '{0}'.", options.SourceFont));
}
// Convert to our desired pixel format.
bitmap = BitmapUtils.ChangePixelFormat(bitmap, PixelFormat.Format32bppArgb);
// What characters are included in this font?
var characters = CharacterRegion.Flatten(options.CharacterRegions).ToArray();
int characterIndex = 0;
char currentCharacter = '\0';
// Split the source image into a list of individual glyphs.
var glyphList = new List<Glyph>();
Glyphs = glyphList;
LineSpacing = 0;
foreach (Rectangle rectangle in FindGlyphs(bitmap))
{
if (characterIndex < characters.Length)
currentCharacter = characters[characterIndex++];
else
currentCharacter++;
glyphList.Add(new Glyph(currentCharacter, bitmap, rectangle));
LineSpacing = Math.Max(LineSpacing, rectangle.Height);
}
// If the bitmap doesn't already have an alpha channel, create one now.
if (BitmapUtils.IsAlphaEntirely(255, bitmap))
{
BitmapUtils.ConvertGreyToAlpha(bitmap);
}
}
public static void Main(string[] args)
{
var options = new CommandLineOptions();
if (!ConsoleProgram.ParseCommandLine(options, args, 32))
{
Environment.Exit(-1);
}
MakeSpriteFont(options);
}
static void MakeSpriteFont(CommandLineOptions options)
{
// Import.
Console.WriteLine("Importing {0}", options.SourceFont);
float lineSpacing;
Glyph[] glyphs = ImportFont(options, out lineSpacing);
// Optimize.
Console.WriteLine("Cropping glyph borders");
foreach (Glyph glyph in glyphs)
{
GlyphCropper.Crop(glyph);
}
Console.WriteLine("Packing glyphs into sprite sheet");
Bitmap bitmap = GlyphPacker.ArrangeGlyphs(glyphs);
// Adjust line and character spacing.
lineSpacing += options.LineSpacing;
foreach (Glyph glyph in glyphs)
{
glyph.XAdvance += options.CharacterSpacing;
}
// Automatically detect whether this is a monochromatic or color font?
if (options.TextureFormat == TextureFormat.Auto)
{
bool isMono = BitmapUtils.IsRgbEntirely(Color.White, bitmap);
options.TextureFormat = isMono ? TextureFormat.CompressedMono :
TextureFormat.Rgba32;
}
// Convert to premultiplied alpha format.
if (!options.NoPremultiply)
{
Console.WriteLine("Premultiplying alpha");
BitmapUtils.PremultiplyAlpha(bitmap);
}
// Save output files.
if (!string.IsNullOrEmpty(options.DebugOutputSpriteSheet))
{
Console.WriteLine("Saving debug output spritesheet {0}", options.DebugOutputSpriteSheet);
bitmap.Save(options.DebugOutputSpriteSheet);
}
Console.WriteLine("Writing {0} ({1} format)", options.OutputFile, options.TextureFormat);
SpriteFontWriter.WriteSpriteFont(options, glyphs, lineSpacing, bitmap);
}
public void Import(CommandLineOptions options)
{
// Create a bunch of GDI+ objects.
using (Font font = CreateFont(options))
using (Brush brush = new SolidBrush(Color.White))
using (StringFormat stringFormat = new StringFormat(StringFormatFlags.NoFontFallback))
using (Bitmap bitmap = new Bitmap(MaxGlyphSize, MaxGlyphSize, PixelFormat.Format32bppArgb))
using (System.Drawing.Graphics graphics = System.Drawing.Graphics.FromImage(bitmap))
{
graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;
graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
graphics.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;
// Which characters do we want to include?
var characters = CharacterRegion.Flatten(options.CharacterRegions);
var glyphList = new List<Glyph>();
// Rasterize each character in turn.
foreach (char character in characters)
{
Glyph glyph = ImportGlyph(character, font, brush, stringFormat, bitmap, graphics);
glyphList.Add(glyph);
}
Glyphs = glyphList;
// Store the font height.
LineSpacing = font.GetHeight();
}
}
static Glyph[] ImportFont(CommandLineOptions options, out float lineSpacing)
{
// Which importer knows how to read this source font?
IFontImporter importer;
string fileExtension = Path.GetExtension(options.SourceFont).ToLowerInvariant();
string[] BitmapFileExtensions = { ".bmp", ".png", ".gif" };
if (BitmapFileExtensions.Contains(fileExtension))
{
importer = new BitmapImporter();
}
else
{
importer = new TrueTypeImporter();
}
// Import the source font data.
importer.Import(options);
lineSpacing = importer.LineSpacing;
var glyphs = importer.Glyphs
.OrderBy(glyph => glyph.Character)
.ToArray();
// Validate.
if (glyphs.Length == 0)
{
throw new Exception("Font does not contain any glyphs.");
}
if ((options.DefaultCharacter != 0) && !glyphs.Any(glyph => glyph.Character == options.DefaultCharacter))
{
throw new Exception("The specified DefaultCharacter is not part of this font.");
}
return glyphs;
}
// Attempts to instantiate the requested GDI+ font object.
static Font CreateFont(CommandLineOptions options)
{
Font font = new Font(options.SourceFont, PointsToPixels(options.FontSize), options.FontStyle, GraphicsUnit.Pixel);
try
{
// The font constructor automatically substitutes fonts if it can't find the one requested.
// But we prefer the caller to know if anything is wrong with their data. A simple string compare
// isn't sufficient because some fonts (eg. MS Mincho) change names depending on the locale.
// Early out: in most cases the name will match the current or invariant culture.
if (options.SourceFont.Equals(font.FontFamily.GetName(CultureInfo.CurrentCulture.LCID), StringComparison.OrdinalIgnoreCase) ||
options.SourceFont.Equals(font.FontFamily.GetName(CultureInfo.InvariantCulture.LCID), StringComparison.OrdinalIgnoreCase))
{
return font;
}
// Check the font name in every culture.
foreach (CultureInfo culture in CultureInfo.GetCultures(CultureTypes.SpecificCultures))
{
if (options.SourceFont.Equals(font.FontFamily.GetName(culture.LCID), StringComparison.OrdinalIgnoreCase))
{
return font;
}
}
// A font substitution must have occurred.
throw new Exception(string.Format("Can't find font '{0}'.", options.SourceFont));
}
catch
{
font.Dispose();
throw;
}
}
public static void WriteSpriteFont(CommandLineOptions options, Glyph[] glyphs, float lineSpacing, Bitmap bitmap)
{
using (FileStream file = File.OpenWrite(options.OutputFile))
using (BinaryWriter writer = new BinaryWriter(file))
{
WriteMagic(writer);
WriteGlyphs(writer, glyphs);
writer.Write(lineSpacing);
writer.Write(options.DefaultCharacter);
WriteBitmap(writer, options, bitmap);
}
}
// We want to compress our font textures, because, like, smaller is better,
// right? But a standard DXT compressor doesn't do a great job with fonts that
// are in premultiplied alpha format. Our font data is greyscale, so all of the
// RGBA channels have the same value. If one channel is compressed differently
// to another, this causes an ugly variation in brightness of the rendered text.
// Also, fonts are mostly either black or white, with grey values only used for
// antialiasing along their edges. It is very important that the black and white
// areas be accurately represented, while the precise value of grey is less
// important.
//
// Trouble is, your average DXT compressor knows nothing about these
// requirements. It will optimize to minimize a generic error metric such as
// RMS, but this will often sacrifice crisp black and white in exchange for
// needless accuracy of the antialiasing pixels, or encode RGB differently to
// alpha. UGLY!
//
// Fortunately, encoding monochrome fonts turns out to be trivial. Using DXT3,
// we can fix the end colors as black and white, which gives guaranteed exact
// encoding of the font inside and outside, plus two fractional values for edge
// antialiasing. Also, these RGB values (0, 1/3, 2/3, 1) map exactly to four of
// the possible 16 alpha values available in DXT3, so we can ensure the RGB and
// alpha channels always exactly match.
static void CompressBlock(BinaryWriter writer, BitmapUtils.PixelAccessor bitmapData, int blockX, int blockY, CommandLineOptions options)
{
long alphaBits = 0;
int rgbBits = 0;
int pixelCount = 0;
for (int y = 0; y < 4; y++)
{
for (int x = 0; x < 4; x++)
{
long alpha;
int rgb;
int value = bitmapData[blockX + x, blockY + y].A;
if (options.NoPremultiply)
{
// If we are not premultiplied, RGB is always white and we have 4 bit alpha.
alpha = value >> 4;
rgb = 0;
}
else
{
// For premultiplied encoding, quantize the source value to 2 bit precision.
if (value < 256 / 6)
{
alpha = 0;
rgb = 1;
}
else if (value < 256 / 2)
{
alpha = 5;
rgb = 3;
}
else if (value < 256 * 5 / 6)
{
alpha = 10;
rgb = 2;
}
else
{
alpha = 15;
rgb = 0;
}
}
// Add this pixel to the alpha and RGB bit masks.
alphaBits |= alpha << (pixelCount * 4);
rgbBits |= rgb << (pixelCount * 2);
pixelCount++;
}
}
// Output the alpha bit mask.
writer.Write(alphaBits);
// Output the two endpoint colors (black and white in 5.6.5 format).
writer.Write((ushort)0xFFFF);
writer.Write((ushort)0);
// Output the RGB bit mask.
writer.Write(rgbBits);
}
// Writes a block compressed monochromatic font texture.
static void WriteCompressedMono(BinaryWriter writer, Bitmap bitmap, CommandLineOptions options)
{
if ((bitmap.Width & 3) != 0 ||
(bitmap.Height & 3) != 0)
{
throw new ArgumentException("Block compression requires texture size to be a multiple of 4.");
}
writer.Write(DXGI_FORMAT_BC2_UNORM);
writer.Write(bitmap.Width * 4);
writer.Write(bitmap.Height / 4);
using (var bitmapData = new BitmapUtils.PixelAccessor(bitmap, ImageLockMode.ReadOnly))
{
for (int y = 0; y < bitmap.Height; y += 4)
{
for (int x = 0; x < bitmap.Width; x += 4)
{
CompressBlock(writer, bitmapData, x, y, options);
}
}
}
}
static void WriteBitmap(BinaryWriter writer, CommandLineOptions options, Bitmap bitmap)
{
writer.Write(bitmap.Width);
writer.Write(bitmap.Height);
switch (options.TextureFormat)
{
case TextureFormat.Rgba32:
WriteRgba32(writer, bitmap);
break;
case TextureFormat.Bgra4444:
WriteBgra4444(writer, bitmap);
break;
case TextureFormat.CompressedMono:
WriteCompressedMono(writer, bitmap, options);
break;
default:
throw new NotSupportedException();
}
}
