/// <summary>
/// Function to register a font within the font cache.
/// </summary>
/// <param name="font">The font to register.</param>
/// <exception cref="ArgumentNullException">Thrown when the <paramref name="font"/> parameter is <b>null</b>.</exception>
/// <exception cref="ArgumentException">Thrown if the <paramref name="font"/> is already registered in the factory cache.</exception>
internal void RegisterFont(GorgonFont font)
{
if (font == null)
{
throw new ArgumentNullException(nameof(font));
}
if (font.Factory != this)
{
throw new ArgumentException(string.Format(Resources.GORGFX_ERR_FONT_ALREADY_REGISTERED, font.Name), nameof(font));
}
lock (_syncLock)
{
if (_fontCache.TryGetValue(font.Name, out GorgonFont existing))
{
// This is the exact same reference, so do nothing.
if (existing == font)
{
return;
}
throw new ArgumentException(string.Format(Resources.GORGFX_ERR_FONT_ALREADY_REGISTERED, font.Name), nameof(font));
}
_fontCache[font.Name] = font;
}
}
/// <summary>
/// Function to unregister a font from the factory cache.
/// </summary>
/// <param name="font">The font to unregister.</param>
/// <exception cref="ArgumentNullException">Thrown when the <paramref name="font"/> parameter is <b>null</b>.</exception>
/// <remarks>
/// <para>
/// This will remove the specified <paramref name="font"/> from the cache, but it will not destroy the font. If a font with the same name exists, but the font is not the same reference as the font passed in
/// then nothing is done and the function will exit, the same happens when the font does not exist in the cache.
/// </para>
/// </remarks>
internal void UnregisterFont(GorgonFont font)
{
if (font == null)
{
throw new ArgumentException(nameof(font));
}
// Don't allow fonts not registered with this factory to be removed from the cache.
if (font.Factory != this)
{
return;
}
lock (_syncLock)
{
if (!_fontCache.TryGetValue(font.Name, out GorgonFont existing))
{
return;
}
// If this font is not the same as the one we want, then do nothing.
if (existing != font)
{
return;
}
_fontCache.Remove(font.Name);
}
}
/// <summary>
/// Function to return or create a new <see cref="GorgonFont"/>.
/// </summary>
/// <param name="fontInfo">The information used to create the font.</param>
/// <returns>A new or existing <see cref="GorgonFont"/>.</returns>
/// <exception cref="ArgumentNullException">Thrown when the <paramref name="fontInfo"/> parameter is <b>null</b>.</exception>
/// <exception cref="ArgumentException">Thrown when the <see cref="IGorgonFontInfo.TextureWidth"/> or <see cref="IGorgonFontInfo.TextureHeight"/> parameters exceed the <see cref="IGorgonVideoAdapterInfo.MaxTextureWidth"/> or
/// <see cref="IGorgonVideoAdapterInfo.MaxTextureHeight"/> available for the current <see cref="FeatureSet"/>.
/// <para>-or-</para>
/// <para>Thrown if the <see cref="IGorgonFontInfo.Characters"/> list does not contain the <see cref="IGorgonFontInfo.DefaultCharacter"/> character.</para>
/// <para>-or-</para>
/// <para>A font with the same name was already created by the factory, but does not have the same parameters.</para>
/// </exception>
/// <remarks>
/// <para>
/// This method creates an object that contains a group of textures with font glyphs. These textures can be used by another application to display text (or symbols) on the screen.
/// Kerning information (the proper spacing for a glyph), advances, etc... are all included for the glyphs with font.
/// </para>
/// <para>
/// The <see cref="IGorgonNamedObject.Name"/> value on the <paramref name="fontInfo"/> parameter is used in caching, and is user defined. It is not necessary to have it share the same name as the
/// font family name in the <paramref name="fontInfo"/> parameter, however it is best practice to indicate the font family name in the name for ease of use. By default, this parameter is set to the
/// font family, height and unit of measure.
/// </para>
/// <para>
/// If a font with the same name was previously created by this factory, then that font will be returned if the <paramref name="fontInfo"/> is the same as the cached version. If the font was not
/// found by its name, then a new font will be created. Otherwise, if a cached font with the same name exists, but its <see cref="IGorgonFontInfo"/> is different from the <paramref name="fontInfo"/>
/// passed in, then an exception will be thrown.
/// </para>
/// </remarks>
public GorgonFont GetFont(IGorgonFontInfo fontInfo)
{
if (fontInfo == null)
{
throw new ArgumentNullException(nameof(fontInfo));
}
lock (_syncLock)
{
// Check the cache for a font with the same name.
if ((_fontCache.TryGetValue(fontInfo.Name, out GorgonFont result)) &&
(!IsFontDifferent(fontInfo, result.Info)))
{
return(result);
}
if (result != null)
{
throw new ArgumentException(string.Format(Resources.GORGFX_ERR_FONT_EXISTS, fontInfo.Name), nameof(fontInfo));
}
if ((fontInfo.TextureWidth > Graphics.VideoAdapter.MaxTextureWidth) ||
(fontInfo.TextureHeight > Graphics.VideoAdapter.MaxTextureHeight))
{
throw new ArgumentException(string.Format(Resources.GORGFX_ERR_FONT_TEXTURE_SIZE_TOO_LARGE,
fontInfo.TextureWidth,
fontInfo.TextureHeight),
nameof(fontInfo));
}
if (!fontInfo.Characters.Contains(fontInfo.DefaultCharacter))
{
throw new ArgumentException(string.Format(Resources.GORGFX_ERR_FONT_DEFAULT_CHAR_DOES_NOT_EXIST, fontInfo.DefaultCharacter));
}
if (Convert.ToInt32(fontInfo.DefaultCharacter) < 32)
{
throw new ArgumentException(string.Format(Resources.GORGFX_ERR_FONT_DEFAULT_CHAR_NOT_VALID, Convert.ToInt32(fontInfo.DefaultCharacter)));
}
// Destroy the previous font if one exists with the same name.
result?.Dispose();
// If not found, then create a new font and cache it.
_fontCache[fontInfo.Name] = result = new GorgonFont(fontInfo.Name, this, fontInfo);
result.GenerateFont(new[] { _externalFonts });
return(result);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="GorgonFontFactory"/> class.
/// </summary>
/// <param name="graphics">The graphics interface used to create the font data.</param>
/// <exception cref="ArgumentNullException">Thrown when the <paramref name="graphics"/> parameter is <b>null</b>.</exception>
public GorgonFontFactory(GorgonGraphics graphics)
{
Graphics = graphics ?? throw new ArgumentNullException(nameof(graphics));
_defaultFont = new Lazy <GorgonFont>(() =>
{
// Create the default font.
var result = new GorgonFont("Gorgon.Font.Default.SegoeUI_9pt",
this,
new GorgonFontInfo("Segoe UI", 9, FontHeightMode.Points)
{
AntiAliasingMode = FontAntiAliasMode.AntiAlias,
FontStyle = FontStyle.Bold,
OutlineSize = 0
});
result.GenerateFont(new[]
{
_externalFonts
});
return(result);
},
true);
}
