public override SpriteFontContent Process(FontDescription input,
ContentProcessorContext context)
{
var output = new SpriteFontContent(input);
var font = new Font(input.FontName, input.Size);
// Make sure that this font is installed on the system.
// Creating a font object with a font that's not contained will default to MS Sans Serif:
// http://msdn.microsoft.com/en-us/library/zet4c3fa.aspx
if (font.FontFamily.Name == "Microsoft Sans Serif" && input.FontName != "Microsoft Sans Serif")
{
throw new PipelineException(string.Format("Font {0} is not installed on this computer.", input.FontName));
}
var estimatedSurfaceArea = 0;
var largestHeight = 0;
var widthsAndHeights = new List <Point>();
// Estimate the bounds of each rect to calculate the
// final texture size
var sf = StringFormat.GenericTypographic;
sf.Trimming = StringTrimming.None;
sf.FormatFlags = StringFormatFlags.MeasureTrailingSpaces;
using (var bmp = new Bitmap((int)(font.Size), (int)(font.Size)))
using (var temp = System.Drawing.Graphics.FromImage(bmp))
{
// Calculate and save the size of each character
foreach (var ch in input.Characters)
{
var charSize = temp.MeasureString(ch.ToString(), font, new PointF(0, 0), sf);
var width = (int)charSize.Width;
var height = (int)charSize.Height;
estimatedSurfaceArea += width;
largestHeight = Math.Max(largestHeight, height);
widthsAndHeights.Add(new Point(width, height));
}
// TODO: Using the largest height will give us some empty space
// This can be optimized to pack a smaller texture if necessary
estimatedSurfaceArea *= largestHeight;
}
output.VerticalLineSpacing = largestHeight;
// calculate the best height and width for our output texture.
// TODO: GetMonoGamePlatform()
var texBounds = calculateOutputTextureBounds(estimatedSurfaceArea, true);
// Create our texture
var outputBitmap = new Bitmap(texBounds.X, texBounds.Y);
using (var g = System.Drawing.Graphics.FromImage(outputBitmap))
{
g.FillRectangle(Brushes.Transparent, new System.Drawing.Rectangle(0, 0, outputBitmap.Width, outputBitmap.Height));
int x = 0;
int y = 0;
// Draw each glyph into the image.
for (int i = 0; i < input.Characters.Count; i++)
{
var kernData = FontHelper.GetCharWidthABC(input.Characters[i], font, g);
int charWidth = (int)(Math.Abs(kernData.abcA) + kernData.abcB + kernData.abcC);
if (!input.UseKerning)
{
charWidth = (int)kernData.abcB;
}
if (x + charWidth >= texBounds.X)
{
x = 0;
y += largestHeight;
}
Rectangle rect = new Microsoft.Xna.Framework.Rectangle(x, y, charWidth, widthsAndHeights[i].Y);
output.Glyphs.Add(rect);
// Characters with a negative a kerning value (like j) need to be adjusted,
// so (in the case of j) the bottom curve doesn't render outside our source
// rect.
var renderPoint = new PointF(x, y);
if (kernData.abcA < 0)
{
renderPoint.X += Math.Abs(kernData.abcA);
}
g.DrawString(input.Characters[i].ToString(), font, Brushes.White, renderPoint, sf);
output.Cropping.Add(new Rectangle(0, 0, charWidth, output.Glyphs[i].Height));
if (!input.UseKerning)
{
kernData.abcA = 0;
kernData.abcC = 0;
}
output.Kerning.Add(new Vector3(kernData.abcA, kernData.abcB, kernData.abcC));
// Add a 2 pixel spacing between characters
x += charWidth + 2;
}
// Drawing against a transparent black background blends
// the 'alpha' pixels against black, leaving a black outline.
// Interpolate between black and white
// based on it's intensity to covert this 'outline' to
// it's grayscale equivalent.
var transBlack = Color.TransparentBlack;
for (var i = 0; i < outputBitmap.Width; i++)
{
for (var j = 0; j < outputBitmap.Height; j++)
{
var px = outputBitmap.GetPixel(i, j);
if (px.ColorsEqual(transBlack))
{
continue;
}
var val = (px.R + px.B + px.G) / (255.0f * 3.0f);
var col = Color.Lerp(Color.Transparent, Color.White, val);
px = System.Drawing.Color.FromArgb(col.A, col.R, col.G, col.B);
outputBitmap.SetPixel(i, j, px);
}
}
var bitmapContent = new PixelBitmapContent <Color>(texBounds.X, texBounds.Y);
bitmapContent.SetPixelData(outputBitmap.GetData());
output.Texture.Faces.Add(new MipmapChain(bitmapContent));
}
return(output);
}