/// <summary>
/// Function to build out the font data.
/// </summary>
/// <param name="graphics">The graphics context to use.</param>
/// <param name="fontInfo">The information used to generate the font.</param>
/// <param name="externalFonts">The external fonts provided by an application.</param>
/// <returns>A new <see cref="GdiFontData"/> object.</returns>
public static GdiFontData GetFontData(System.Drawing.Graphics graphics, IGorgonFontInfo fontInfo, IEnumerable <PrivateFontCollection> externalFonts)
{
var result = new GdiFontData();
CharacterRange[] range =
{
new CharacterRange(0, 1)
};
System.Drawing.FontStyle style = System.Drawing.FontStyle.Regular;
switch (fontInfo.FontStyle)
{
case FontStyle.Bold:
style = System.Drawing.FontStyle.Bold;
break;
case FontStyle.Italics:
style = System.Drawing.FontStyle.Italic;
break;
case FontStyle.BoldItalics:
style = System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic;
break;
}
FontFamily fontFamily = (externalFonts != null ? (externalFonts.SelectMany(item => item.Families).Concat(FontFamily.Families)) : FontFamily.Families)
.FirstOrDefault(item => string.Equals(fontInfo.FontFamilyName, item.Name, StringComparison.InvariantCultureIgnoreCase));
// If we cannot locate the font family by name, then fall back.
if (fontFamily == null)
{
fontFamily = FontFamily.GenericSerif;
}
// Scale the font appropriately.
if (fontInfo.FontHeightMode == FontHeightMode.Points)
{
// Convert the internal font to pixel size.
result.Font = new Font(fontFamily,
(fontInfo.Size * graphics.DpiY) / 72.0f,
style,
GraphicsUnit.Pixel);
}
else
{
result.Font = new Font(fontFamily, fontInfo.Size, style, GraphicsUnit.Pixel);
}
result.FontHeight = result.Font.GetHeight(graphics);
result.StringFormat = new StringFormat(StringFormat.GenericTypographic)
{
FormatFlags = StringFormatFlags.NoFontFallback | StringFormatFlags.MeasureTrailingSpaces,
Alignment = StringAlignment.Near,
LineAlignment = StringAlignment.Near
};
result.StringFormat.SetMeasurableCharacterRanges(range);
// Create a separate drawing format because some glyphs are being clipped when they have overhang
// on the left boundary.
result.DrawFormat = new StringFormat(StringFormat.GenericDefault)
{
FormatFlags = StringFormatFlags.NoFontFallback | StringFormatFlags.MeasureTrailingSpaces,
Alignment = StringAlignment.Near,
LineAlignment = StringAlignment.Near
};
result.DrawFormat.SetMeasurableCharacterRanges(range);
return(result);
}
/// <summary>
/// Initializes a new instance of the <see cref="GlyphDraw"/> class.
/// </summary>
/// <param name="fontInfo">The font information used to create the font.</param>
/// <param name="fontData">The font data for the glyphs.</param>
public GlyphDraw(IGorgonFontInfo fontInfo, GdiFontData fontData)
{
_fontInfo = fontInfo;
_fontData = fontData;
}
/// <summary>
/// Function to create or update the font.
/// </summary>
/// <param name="externalFontCollections">The external font collections from the application.</param>
/// <remarks>
/// <para>
/// This is used to generate a new set of font textures, and essentially "create" the font object.
/// </para>
/// <para>
/// This method will clear all the glyphs and textures in the font and rebuild the font with the specified parameters. This means that any custom glyphs, texture mapping, and/or kerning will be lost.
/// Users must find a way to remember and restore any custom font info when updating.
/// </para>
/// <para>
/// Internal textures used by the glyph will be destroyed. However, if there's a user defined texture or glyph using a user defined texture, then it will not be destroyed and clean up will be the
/// responsibility of the user.
/// </para>
/// </remarks>
/// <exception cref="GorgonException">Thrown when the texture size in the settings exceeds that of the capabilities of the feature level.
/// <para>-or-</para>
/// <para>Thrown when the font family name is <b>null</b> or Empty.</para>
/// </exception>
internal void GenerateFont(IEnumerable <System.Drawing.Text.PrivateFontCollection> externalFontCollections)
{
Bitmap setupBitmap = null;
System.Drawing.Graphics graphics = null;
GdiFontData fontData = default;
Dictionary <Bitmap, IEnumerable <GlyphInfo> > groupedByBitmap = null;
try
{
// Temporary bitmap used to gather a graphics context.
setupBitmap = new Bitmap(2, 2, PixelFormat.Format32bppArgb);
// Get a context for the rasterizing surface.
graphics = System.Drawing.Graphics.FromImage(setupBitmap);
graphics.PageUnit = GraphicsUnit.Pixel;
// Build up the information using a GDI+ font.
fontData = GdiFontData.GetFontData(graphics, Info, externalFontCollections);
// Remove control characters and anything below a space.
List <char> availableCharacters = GetAvailableCharacters();
// Set up the code to draw glyphs to bitmaps.
var glyphDraw = new GlyphDraw(Info, fontData);
// Gather the boundaries for each glyph character.
Dictionary <char, GlyphRegions> glyphBounds = glyphDraw.GetGlyphRegions(availableCharacters, HasOutline);
// Because the dictionary above remaps characters (if they don't have a glyph or their rects are empty),
// we'll need to drop these from our main list of characters.
availableCharacters.RemoveAll(item => !glyphBounds.ContainsKey(item));
// Get kerning and glyph advancement information.
Dictionary <char, ABC> abcAdvances = GetKerningInformation(graphics, fontData.Font, availableCharacters);
// Put the glyphs on packed bitmaps.
Dictionary <char, GlyphInfo> glyphBitmaps = glyphDraw.DrawToPackedBitmaps(availableCharacters, glyphBounds, HasOutline);
groupedByBitmap = (from glyphBitmap in glyphBitmaps
where glyphBitmap.Value.GlyphBitmap != null
group glyphBitmap.Value by glyphBitmap.Value.GlyphBitmap).ToDictionary(k => k.Key, v => v.Select(item => item));
// Generate textures from the bitmaps.
// We will pack each bitmap into a single arrayed texture up to the maximum number of array indices allowed.
// Once that limit is reached a new texture will be used. This should help performance a little, although it
// is much better to resize the texture so that it has a single array index and single texture.
GenerateTextures(groupedByBitmap);
// Finally, generate our glyphs.
GenerateGlyphs(glyphBitmaps, abcAdvances);
FontHeight = fontData.FontHeight;
Ascent = fontData.Ascent;
Descent = fontData.Descent;
LineHeight = fontData.LineHeight;
}
finally
{
graphics?.Dispose();
setupBitmap?.Dispose();
fontData?.Dispose();
if (groupedByBitmap != null)
{
foreach (Bitmap glyphBitmap in groupedByBitmap.Keys)
{
glyphBitmap.Dispose();
}
}
}
}
