HellionChat/HellionChat/FontManager.cs

using Dalamud;
using Dalamud.Bindings.ImGui;
using Dalamud.Interface;
using Dalamud.Interface.FontIdentifier;
using Dalamud.Interface.GameFonts;
using Dalamud.Interface.ManagedFontAtlas;
using Dalamud.Interface.Utility;

namespace HellionChat;

public class FontManager
{
    internal IFontHandle Axis = null!;
    internal IFontHandle AxisItalic = null!;

    internal IFontHandle RegularFont = null!;
    internal IFontHandle? ItalicFont;

    internal IFontHandle FontAwesome = null!;

    private ushort[] Ranges = [];
    private ushort[] JpRange = [];

    public static readonly HashSet<float> AxisFontSizeList =
    [
        9.6f,
        10f,
        12f,
        14f,
        16f,
        18f,
        18.4f,
        20f,
        23f,
        34f,
        36f,
        40f,
        45f,
        46f,
        68f,
        90f,
    ];

    // Hellion font bytes (Exo 2, OFL-1.1); lazily loaded from manifest resources
    private static byte[]? HellionFontBytes;

    private static byte[] GetHellionFontBytes()
    {
        if (HellionFontBytes is not null)
            return HellionFontBytes;

        using var stream =
            typeof(FontManager).Assembly.GetManifestResourceStream("HellionFont.ttf")
            ?? throw new FileNotFoundException(
                "Hellion font resource not embedded in the assembly"
            );
        using var ms = new MemoryStream();
        stream.CopyTo(ms);
        HellionFontBytes = ms.ToArray();
        return HellionFontBytes;
    }

    private unsafe void SetUpRanges()
    {
        ushort[] BuildRange(IReadOnlyList<ushort>? chars, params nint[] ranges)
        {
            var builder = new ImFontGlyphRangesBuilderPtr(ImGuiNative.ImFontGlyphRangesBuilder());
            foreach (var range in ranges)
                builder.AddRanges((ushort*)range);

            if (chars != null)
            {
                for (var i = 0; i < chars.Count; i += 2)
                {
                    if (chars[i] == 0)
                        break;

                    for (var j = (uint)chars[i]; j <= chars[i + 1]; j++)
                        builder.AddChar((ushort)j);
                }
            }

            // Ingame supported ranges
            var reader = new FdtReader(Plugin.DataManager.GetFile("common/font/axis_12.fdt")!.Data);
            foreach (var c in reader.Glyphs)
                builder.AddChar(c.Char);

            // various symbols
            // French
            // Romanian
            // builder.AddText("←→↑↓《》■※☀★★☆♥♡ヅツッシ☀☁☂℃℉°♀♂♠♣♦♣♧®©™€$£♯♭♪✓√◎◆◇♦■□〇●△▽▼▲‹›≤≥<«“”─＼～");
            builder.AddText("Œœ");
            builder.AddText("ĂăÂâÎîȘșȚț");

            // "Enclosed Alphanumerics" (partial) https://www.compart.com/en/unicode/block/U+2460
            for (var i = 0x2460; i <= 0x24B5; i++)
                builder.AddChar((char)i);

            builder.AddChar('⓪');
            return builder.BuildRangesToArray();
        }

        var ranges = new List<nint> { (nint)ImGui.GetIO().Fonts.GetGlyphRangesDefault() };
        foreach (var extraRange in Enum.GetValues<ExtraGlyphRanges>())
            if (Plugin.Config.ExtraGlyphRanges.HasFlag(extraRange))
                ranges.Add(extraRange.Range());

        Ranges = BuildRange(null, ranges.ToArray());
        JpRange = BuildRange(GlyphRangesJapanese.GlyphRanges);
    }

    // CPU-bound build offloaded to Task.Run; runs parallel with theme init
    public async Task BuildFontsAsync(CancellationToken cancellationToken)
    {
        cancellationToken.ThrowIfCancellationRequested();
        await Task.Run(BuildFonts, cancellationToken).ConfigureAwait(false);
    }

    public void BuildFonts()
    {
        SetUpRanges();

        Axis = Plugin.Interface.UiBuilder.FontAtlas.NewGameFontHandle(
            new GameFontStyle(GameFontFamily.Axis, SizeInPx(Plugin.Config.FontSizeV2))
        );
        AxisItalic = Plugin.Interface.UiBuilder.FontAtlas.NewGameFontHandle(
            new GameFontStyle(GameFontFamily.Axis, SizeInPx(Plugin.Config.FontSizeV2))
            {
                SkewStrength = SizeInPx(Plugin.Config.FontSizeV2) / 6,
            }
        );

        FontAwesome = Plugin.Interface.UiBuilder.FontAtlas.NewDelegateFontHandle(e =>
        {
            e.OnPreBuild(tk =>
                tk.AddFontAwesomeIconFont(new SafeFontConfig { SizePx = GetFontSize() })
            );
            e.OnPostBuild(tk => tk.FitRatio(tk.Font));
        });

        RegularFont = Plugin.Interface.UiBuilder.FontAtlas.NewDelegateFontHandle(e =>
            e.OnPreBuild(tk =>
            {
                // v1.2.0: UseHellionFont controls font size selection
                var basePt = Plugin.Config.UseHellionFont
                    ? Plugin.Config.FontSizeV2
                    : Plugin.Config.GlobalFontV2.SizePt;
                var config = new SafeFontConfig { SizePt = basePt, GlyphRanges = Ranges };
                config.MergeFont = Plugin.Config.UseHellionFont
                    ? tk.AddFontFromMemory(GetHellionFontBytes(), config, "Hellion-Exo2")
                    : AddFontWithFallback(tk, Plugin.Config.GlobalFontV2.FontId, config, "global");

                config.SizePt = Plugin.Config.JapaneseFontV2.SizePt;
                config.GlyphRanges = JpRange;
                AddFontWithFallback(tk, Plugin.Config.JapaneseFontV2.FontId, config, "japanese");

                config.SizePt = Plugin.Config.SymbolsFontSizeV2;
                tk.AddGameSymbol(config);

                tk.Font = config.MergeFont;
            })
        );

        if (Plugin.Config.ItalicEnabled)
        {
            ItalicFont = Plugin.Interface.UiBuilder.FontAtlas.NewDelegateFontHandle(e =>
                e.OnPreBuild(tk =>
                {
                    var config = new SafeFontConfig
                    {
                        SizePt = Plugin.Config.ItalicFontV2.SizePt,
                        GlyphRanges = Ranges,
                    };
                    config.MergeFont = AddFontWithFallback(
                        tk,
                        Plugin.Config.ItalicFontV2.FontId,
                        config,
                        "italic"
                    );

                    config.SizePt = Plugin.Config.JapaneseFontV2.SizePt;
                    config.GlyphRanges = JpRange;
                    AddFontWithFallback(
                        tk,
                        Plugin.Config.JapaneseFontV2.FontId,
                        config,
                        "japanese"
                    );

                    config.SizePt = Plugin.Config.SymbolsFontSizeV2;
                    tk.AddGameSymbol(config);

                    tk.Font = config.MergeFont;
                })
            );
        }
        else
        {
            ItalicFont = null;
        }
    }

    // Add font with fallback to NotoSansCjkRegular if unavailable
    private static ImFontPtr AddFontWithFallback(
        IFontAtlasBuildToolkitPreBuild tk,
        IFontId fontId,
        SafeFontConfig config,
        string slot
    )
    {
        try
        {
            return fontId.AddToBuildToolkit(tk, config);
        }
        catch (Exception e)
            when (e is FileNotFoundException or DirectoryNotFoundException or IOException)
        {
            Plugin.Log.Warning(
                e,
                $"Configured {slot} font unavailable, falling back to NotoSansCjkRegular"
            );
            var fallback = new DalamudAssetFontAndFamilyId(DalamudAsset.NotoSansCjkRegular);
            return fallback.AddToBuildToolkit(tk, config);
        }
    }

    public static float SizeInPt(float px) => (float)(px * 3.0 / 4.0);

    public static float SizeInPx(float pt) => (float)(pt * 4.0 / 3.0);

    public static float GetFontSize() =>
        Plugin.Config.FontsEnabled
            ? Plugin.Config.GlobalFontV2.SizePx
            : SizeInPx(Plugin.Config.FontSizeV2);
}