osu-lazer/osu.Game/Skinning/LegacySpriteText.cs

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.

using System.Threading.Tasks;
using osu.Framework.Graphics.Sprites;
using osu.Framework.Text;
using osu.Game.Graphics;
using osu.Game.Graphics.Sprites;

namespace osu.Game.Skinning
{
    public class LegacySpriteText : OsuSpriteText
    {
        private readonly LegacyGlyphStore glyphStore;

        public LegacySpriteText(ISkin skin, string font)
        {
            Shadow = false;
            UseFullGlyphHeight = false;

            Font = new FontUsage(font, OsuFont.DEFAULT_FONT_SIZE);
            glyphStore = new LegacyGlyphStore(skin);
        }

        protected override TextBuilder CreateTextBuilder(ITexturedGlyphLookupStore store) => base.CreateTextBuilder(glyphStore);

        private class LegacyGlyphStore : ITexturedGlyphLookupStore
        {
            private readonly ISkin skin;

            public LegacyGlyphStore(ISkin skin)
            {
                this.skin = skin;
            }

            public ITexturedCharacterGlyph Get(string fontName, char character)
            {
                var texture = skin.GetTexture($"{fontName}-{character}");

                if (texture != null)
                    // Approximate value that brings character sizing roughly in-line with stable
                    texture.ScaleAdjust *= 18;

                if (texture == null)
                    return null;

                return new TexturedCharacterGlyph(new CharacterGlyph(character, 0, 0, texture.Width, null), texture, 1f / texture.ScaleAdjust);
            }

            public Task<ITexturedCharacterGlyph> GetAsync(string fontName, char character) => Task.Run(() => Get(fontName, character));
        }
    }
}