Add SetFontScaleMode(ImFontPtr, FontScaleMode) (#1666)

* Add SetFontScaleMode(ImFontPtr, FontScaleMode)

`IgnoreGlobalScale` was advertised as "excludes the given font from
global scaling", but the intent I had in mind was "excludes the given
font from being scaled in any manner". As the latter functionality is
needed, obsoleted `IgnoreGlobalScale` and added `SetFontScaleMode`.

* Make it correct

* Name consistency

Dalamud/Interface/FontIdentifier/IFontSpec.cs

@@ -31,6 +31,8 @@ public interface IFontSpec
     /// <param name="atlas">The atlas to bind this font handle to.</param>
     /// <param name="callback">Optional callback to be called after creating the font handle.</param>
     /// <returns>The new font handle.</returns>
+    /// <remarks><see cref="IFontAtlasBuildToolkit.Font"/> will be set when <paramref name="callback"/> is invoked.
+    /// </remarks>
     IFontHandle CreateFontHandle(IFontAtlas atlas, FontAtlasBuildStepDelegate? callback = null);
 
     /// <summary>

Dalamud/Interface/FontIdentifier/SingleFontSpec.cs

@@ -109,7 +109,9 @@ public record SingleFontSpec : IFontSpec
         tk.RegisterPostBuild(
             () =>
             {
-                var roundUnit = tk.IsGlobalScaleIgnored(font) ? 1 : 1 / tk.Scale;
+                // Multiplication by scale will be done with global scale, outside of this handling.
+                var scale = tk.GetFontScaleMode(font) == FontScaleMode.UndoGlobalScale ? 1 / tk.Scale : 1;
+                var roundUnit = tk.GetFontScaleMode(font) == FontScaleMode.SkipHandling ? 1 : 1 / tk.Scale;
                 var newAscent = MathF.Round((font.Ascent * this.LineHeight) / roundUnit) * roundUnit;
                 var newFontSize = MathF.Round((font.FontSize * this.LineHeight) / roundUnit) * roundUnit;
                 var shiftDown = MathF.Round((newFontSize - font.FontSize) / 2f / roundUnit) * roundUnit;
@@ -129,13 +131,10 @@ public record SingleFontSpec : IFontSpec
                     }
                 }
 
-                // `/ roundUnit` = `* scale`
+                var dax = MathF.Round((this.LetterSpacing * scale) / roundUnit) * roundUnit;
-                var dax = MathF.Round(this.LetterSpacing / roundUnit / roundUnit) * roundUnit;
+                var dxy0 = this.GlyphOffset * scale;
-                var dxy0 = this.GlyphOffset / roundUnit;
-
                 dxy0 /= roundUnit;
-                dxy0.X = MathF.Round(dxy0.X);
+                dxy0 = new(MathF.Round(dxy0.X), MathF.Round(dxy0.Y));
-                dxy0.Y = MathF.Round(dxy0.Y);
                 dxy0 *= roundUnit;
 
                 dxy0.Y += shiftDown;

Dalamud/Interface/ImGuiFontChooserDialog/SingleFontChooserDialog.cs

@@ -342,9 +342,7 @@ public sealed class SingleFontChooserDialog : IDisposable
         {
             this.fontHandle ??= this.selectedFont.CreateFontHandle(
                 this.atlas,
-                tk =>
+                tk => tk.OnPreBuild(e => e.SetFontScaleMode(e.Font, FontScaleMode.UndoGlobalScale)));
-                    tk.OnPreBuild(e => e.IgnoreGlobalScale(e.Font))
-                      .OnPostBuild(e => e.Font.AdjustGlyphMetrics(1f / e.Scale)));
         }
         else
         {
@@ -837,7 +835,7 @@ public sealed class SingleFontChooserDialog : IDisposable
         var changed = false;
 
         if (!ImGui.BeginTable("##advancedOptions", 4))
-            return changed;
+            return false;
 
         var labelWidth = ImGui.CalcTextSize("Letter Spacing:").X;
         labelWidth = Math.Max(labelWidth, ImGui.CalcTextSize("Offset:").X);

Dalamud/Interface/Internal/Windows/Data/Widgets/GamePrebakedFontsTestWidget.cs

@@ -25,12 +25,20 @@ namespace Dalamud.Interface.Internal.Windows.Data.Widgets;
 /// </summary>
 internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
 {
+    private static readonly string[] FontScaleModes =
+    {
+        nameof(FontScaleMode.Default),
+        nameof(FontScaleMode.SkipHandling),
+        nameof(FontScaleMode.UndoGlobalScale),
+    };
+
     private ImVectorWrapper<byte> testStringBuffer;
     private IFontAtlas? privateAtlas;
     private SingleFontSpec fontSpec = new() { FontId = DalamudDefaultFontAndFamilyId.Instance };
     private IFontHandle? fontDialogHandle;
     private IReadOnlyDictionary<GameFontFamily, (GameFontStyle Size, Lazy<IFontHandle> Handle)[]>? fontHandles;
-    private bool useGlobalScale;
+    private bool atlasScaleMode = true;
+    private int fontScaleMode = (int)FontScaleMode.UndoGlobalScale;
     private bool useWordWrap;
     private bool useItalic;
     private bool useBold;
@@ -52,12 +60,14 @@ internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
     public unsafe void Draw()
     {
         ImGui.AlignTextToFramePadding();
-        fixed (byte* labelPtr = "Global Scale"u8)
+        if (ImGui.Combo("Global Scale per Font", ref this.fontScaleMode, FontScaleModes, FontScaleModes.Length))
+            this.ClearAtlas();
+        fixed (byte* labelPtr = "Global Scale for Atlas"u8)
         {
-            var v = (byte)(this.useGlobalScale ? 1 : 0);
+            var v = (byte)(this.atlasScaleMode ? 1 : 0);
             if (ImGuiNative.igCheckbox(labelPtr, &v) != 0)
             {
-                this.useGlobalScale = v != 0;
+                this.atlasScaleMode = v != 0;
                 this.ClearAtlas();
             }
         }
@@ -124,7 +134,7 @@ internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
                     $"{nameof(GamePrebakedFontsTestWidget)}:EditorFont",
                     FontAtlasAutoRebuildMode.Async));
             fcd.SelectedFont = this.fontSpec;
-            fcd.IgnorePreviewGlobalScale = !this.useGlobalScale;
+            fcd.IgnorePreviewGlobalScale = !this.atlasScaleMode;
             Service<InterfaceManager>.Get().Draw += fcd.Draw;
             fcd.ResultTask.ContinueWith(
                 r => Service<Framework>.Get().RunOnFrameworkThread(
@@ -148,12 +158,14 @@ internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
             Service<FontAtlasFactory>.Get().CreateFontAtlas(
                 nameof(GamePrebakedFontsTestWidget),
                 FontAtlasAutoRebuildMode.Async,
-                this.useGlobalScale);
+                this.atlasScaleMode);
-        this.fontDialogHandle ??= this.fontSpec.CreateFontHandle(this.privateAtlas);
+        this.fontDialogHandle ??= this.fontSpec.CreateFontHandle(
+            this.privateAtlas,
+            e => e.OnPreBuild(tk => tk.SetFontScaleMode(tk.Font, (FontScaleMode)this.fontScaleMode)));
 
         fixed (byte* labelPtr = "Test Input"u8)
         {
-            if (!this.useGlobalScale)
+            if (!this.atlasScaleMode)
                 ImGuiNative.igSetWindowFontScale(1 / ImGuiHelpers.GlobalScale);
             using (this.fontDialogHandle.Push())
             {
@@ -180,7 +192,7 @@ internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
                 }
             }
 
-            if (!this.useGlobalScale)
+            if (!this.atlasScaleMode)
                 ImGuiNative.igSetWindowFontScale(1);
         }
 
@@ -192,17 +204,29 @@ internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
                 .ToImmutableDictionary(
                     x => x.Key,
                     x => x.Select(
-                              y => (y, new Lazy<IFontHandle>(
+                              y =>
-                                           () => this.useMinimumBuild
+                              {
-                                                     ? this.privateAtlas.NewDelegateFontHandle(
+                                  var range = Encoding.UTF8.GetString(this.testStringBuffer.DataSpan).ToGlyphRange();
-                                                         e =>
+
-                                                             e.OnPreBuild(
+                                  Lazy<IFontHandle> l;
-                                                                 tk => tk.AddGameGlyphs(
+                                  if (this.useMinimumBuild
-                                                                     y,
+                                      || (this.atlasScaleMode && this.fontScaleMode != (int)FontScaleMode.Default))
-                                                                     Encoding.UTF8.GetString(
+                                  {
-                                                                         this.testStringBuffer.DataSpan).ToGlyphRange(),
+                                      l = new(
-                                                                     default)))
+                                          () => this.privateAtlas!.NewDelegateFontHandle(
-                                                     : this.privateAtlas.NewGameFontHandle(y))))
+                                              e =>
+                                                  e.OnPreBuild(
+                                                      tk => tk.SetFontScaleMode(
+                                                          tk.AddGameGlyphs(y, range, default),
+                                                          (FontScaleMode)this.fontScaleMode))));
+                                  }
+                                  else
+                                  {
+                                      l = new(() => this.privateAtlas!.NewGameFontHandle(y));
+                                  }
+
+                                  return (y, l);
+                              })
                           .ToArray());
 
         var offsetX = ImGui.CalcTextSize("99.9pt").X + (ImGui.GetStyle().FramePadding.X * 2);
@@ -230,7 +254,7 @@ internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
                     }
                     else
                     {
-                        if (!this.useGlobalScale)
+                        if (!this.atlasScaleMode)
                             ImGuiNative.igSetWindowFontScale(1 / ImGuiHelpers.GlobalScale);
                         if (counter++ % 2 == 0)
                         {
@@ -251,8 +275,8 @@ internal class GamePrebakedFontsTestWidget : IDataWindowWidget, IDisposable
                 }
                 finally
                 {
-                    ImGuiNative.igPopTextWrapPos();
                     ImGuiNative.igSetWindowFontScale(1);
+                    ImGuiNative.igPopTextWrapPos();
                 }
             }
         }

Dalamud/Interface/ManagedFontAtlas/FontScaleMode.cs

@@ -0,0 +1,33 @@
+using Dalamud.Interface.Utility;
+
+using ImGuiNET;
+
+namespace Dalamud.Interface.ManagedFontAtlas;
+
+/// <summary>
+/// Specifies how should global font scale affect a font.
+/// </summary>
+public enum FontScaleMode
+{
+    /// <summary>
+    /// Do the default handling. Dalamud will load the sufficienty large font that will accomodate the global scale,
+    /// and stretch the loaded glyphs so that they look pixel-perfect after applying global scale on drawing.
+    /// Note that bitmap fonts and game fonts will always look blurry if they're not in their original sizes.
+    /// </summary>
+    Default,
+    
+    /// <summary>
+    /// Do nothing with the font. Dalamud will load the font with the size that is exactly as specified.
+    /// On drawing, the font will look blurry due to stretching.
+    /// Intended for use with custom scale handling.
+    /// </summary>
+    SkipHandling,
+    
+    /// <summary>
+    /// Stretch the glyphs of the loaded font by the inverse of the global scale.
+    /// On drawing, the font will always render exactly as the requested size without blurring, as long as
+    /// <see cref="ImGuiHelpers.GlobalScale"/> and <see cref="ImGui.SetWindowFontScale"/> do not affect the scale any
+    /// further. Note that bitmap fonts and game fonts will always look blurry if they're not in their original sizes.
+    /// </summary>
+    UndoGlobalScale,
+}

Dalamud/Interface/ManagedFontAtlas/IFontAtlasBuildToolkitPostBuild.cs

@@ -1,4 +1,5 @@
 using Dalamud.Interface.Internal;
+using Dalamud.Utility;
 
 using ImGuiNET;
 
@@ -10,12 +11,13 @@ namespace Dalamud.Interface.ManagedFontAtlas;
 /// </summary>
 public interface IFontAtlasBuildToolkitPostBuild : IFontAtlasBuildToolkit
 {
-    /// <summary>
+    /// <inheritdoc cref="IFontAtlasBuildToolkitPreBuild.IsGlobalScaleIgnored"/>
-    /// Gets whether global scaling is ignored for the given font.
+    [Obsolete($"Use {nameof(this.GetFontScaleMode)}")]
-    /// </summary>
+    [Api10ToDo(Api10ToDoAttribute.DeleteCompatBehavior)]
-    /// <param name="fontPtr">The font.</param>
+    bool IsGlobalScaleIgnored(ImFontPtr fontPtr) => this.GetFontScaleMode(fontPtr) == FontScaleMode.UndoGlobalScale;
-    /// <returns>True if ignored.</returns>
+
-    bool IsGlobalScaleIgnored(ImFontPtr fontPtr);
+    /// <inheritdoc cref="IFontAtlasBuildToolkitPreBuild.GetFontScaleMode"/>
+    FontScaleMode GetFontScaleMode(ImFontPtr fontPtr);
 
     /// <summary>
     /// Stores a texture to be managed with the atlas.

Dalamud/Interface/ManagedFontAtlas/IFontAtlasBuildToolkitPreBuild.cs

@@ -4,6 +4,7 @@ using System.Runtime.InteropServices;
 using Dalamud.Interface.FontIdentifier;
 using Dalamud.Interface.GameFonts;
 using Dalamud.Interface.Utility;
+using Dalamud.Utility;
 
 using ImGuiNET;
 
@@ -45,14 +46,37 @@ public interface IFontAtlasBuildToolkitPreBuild : IFontAtlasBuildToolkit
     /// </summary>
     /// <param name="fontPtr">The font.</param>
     /// <returns>Same <see cref="ImFontPtr"/> with <paramref name="fontPtr"/>.</returns>
-    ImFontPtr IgnoreGlobalScale(ImFontPtr fontPtr);
+    [Obsolete(
+        $"Use {nameof(this.SetFontScaleMode)} with {nameof(FontScaleMode)}.{nameof(FontScaleMode.UndoGlobalScale)}")]
+    [Api10ToDo(Api10ToDoAttribute.DeleteCompatBehavior)]
+    ImFontPtr IgnoreGlobalScale(ImFontPtr fontPtr) => this.SetFontScaleMode(fontPtr, FontScaleMode.UndoGlobalScale);
 
     /// <summary>
     /// Gets whether global scaling is ignored for the given font.
     /// </summary>
     /// <param name="fontPtr">The font.</param>
     /// <returns>True if ignored.</returns>
-    bool IsGlobalScaleIgnored(ImFontPtr fontPtr);
+    [Obsolete($"Use {nameof(this.GetFontScaleMode)}")]
+    [Api10ToDo(Api10ToDoAttribute.DeleteCompatBehavior)]
+    bool IsGlobalScaleIgnored(ImFontPtr fontPtr) => this.GetFontScaleMode(fontPtr) == FontScaleMode.UndoGlobalScale;
+
+    /// <summary>
+    /// Sets the scaling mode for the given font.
+    /// </summary>
+    /// <param name="fontPtr">The font, returned from <see cref="AddFontFromFile"/> and alike.
+    /// Note that <see cref="IFontAtlasBuildToolkit.Font"/> property is not guaranteed to be automatically updated upon
+    /// calling font adding functions. Pass the return value from font adding functions, not
+    /// <see cref="IFontAtlasBuildToolkit.Font"/> property.</param>
+    /// <param name="mode">The scaling mode.</param>
+    /// <returns><paramref name="fontPtr"/>.</returns>
+    ImFontPtr SetFontScaleMode(ImFontPtr fontPtr, FontScaleMode mode);
+
+    /// <summary>
+    /// Gets the scaling mode for the given font.
+    /// </summary>
+    /// <param name="fontPtr">The font.</param>
+    /// <returns>The scaling mode.</returns>
+    FontScaleMode GetFontScaleMode(ImFontPtr fontPtr);
 
     /// <summary>
     /// Registers a function to be run after build.

Dalamud/Interface/ManagedFontAtlas/Internals/FontAtlasFactory.BuildToolkit.cs

@@ -83,9 +83,9 @@ internal sealed partial class FontAtlasFactory
         public ImVectorWrapper<ImFontPtr> Fonts => this.data.Fonts;
 
         /// <summary>
-        /// Gets the list of fonts to ignore global scale.
+        /// Gets the font scale modes.
         /// </summary>
-        public List<ImFontPtr> GlobalScaleExclusions { get; } = new();
+        private Dictionary<ImFontPtr, FontScaleMode> FontScaleModes { get; } = new();
 
         /// <inheritdoc/>
         public void Dispose() => this.disposeAfterBuild.Dispose();
@@ -151,15 +151,15 @@ internal sealed partial class FontAtlasFactory
         }
 
         /// <inheritdoc/>
-        public ImFontPtr IgnoreGlobalScale(ImFontPtr fontPtr)
+        public ImFontPtr SetFontScaleMode(ImFontPtr fontPtr, FontScaleMode scaleMode)
         {
-            this.GlobalScaleExclusions.Add(fontPtr);
+            this.FontScaleModes[fontPtr] = scaleMode;
             return fontPtr;
         }
 
-        /// <inheritdoc cref="IFontAtlasBuildToolkitPreBuild.IsGlobalScaleIgnored"/>
+        /// <inheritdoc cref="IFontAtlasBuildToolkitPreBuild.GetFontScaleMode"/>
-        public bool IsGlobalScaleIgnored(ImFontPtr fontPtr) =>
+        public FontScaleMode GetFontScaleMode(ImFontPtr fontPtr) =>
-            this.GlobalScaleExclusions.Contains(fontPtr);
+            this.FontScaleModes.GetValueOrDefault(fontPtr, FontScaleMode.Default);
 
         /// <inheritdoc/>
         public int StoreTexture(IDalamudTextureWrap textureWrap, bool disposeOnError) =>
@@ -496,17 +496,17 @@ internal sealed partial class FontAtlasFactory
             var configData = this.data.ConfigData;
             foreach (ref var config in configData.DataSpan)
             {
-                if (this.GlobalScaleExclusions.Contains(new(config.DstFont)))
+                if (this.GetFontScaleMode(config.DstFont) != FontScaleMode.Default)
                     continue;
 
                 config.SizePixels *= this.Scale;
 
                 config.GlyphMaxAdvanceX *= this.Scale;
-                if (float.IsInfinity(config.GlyphMaxAdvanceX))
+                if (float.IsInfinity(config.GlyphMaxAdvanceX) || float.IsNaN(config.GlyphMaxAdvanceX))
                     config.GlyphMaxAdvanceX = config.GlyphMaxAdvanceX > 0 ? float.MaxValue : -float.MaxValue;
 
                 config.GlyphMinAdvanceX *= this.Scale;
-                if (float.IsInfinity(config.GlyphMinAdvanceX))
+                if (float.IsInfinity(config.GlyphMinAdvanceX) || float.IsNaN(config.GlyphMinAdvanceX))
                     config.GlyphMinAdvanceX = config.GlyphMinAdvanceX > 0 ? float.MaxValue : -float.MaxValue;
 
                 config.GlyphOffset *= this.Scale;
@@ -536,7 +536,7 @@ internal sealed partial class FontAtlasFactory
             var scale = this.Scale;
             foreach (ref var font in this.Fonts.DataSpan)
             {
-                if (!this.GlobalScaleExclusions.Contains(font))
+                if (this.GetFontScaleMode(font) != FontScaleMode.SkipHandling)
                     font.AdjustGlyphMetrics(1 / scale, 1 / scale);
 
                 foreach (var c in FallbackCodepoints)

Dalamud/Interface/ManagedFontAtlas/Internals/GamePrebakedFontHandle.cs

@@ -345,17 +345,36 @@ internal class GamePrebakedFontHandle : FontHandle
         {
             foreach (var (font, style, ranges) in this.attachments)
             {
-                var effectiveStyle =
-                    toolkitPreBuild.IsGlobalScaleIgnored(font)
-                        ? style.Scale(1 / toolkitPreBuild.Scale)
-                        : style;
                 if (!this.fonts.TryGetValue(style, out var plan))
                 {
-                    plan = new(
+                    switch (toolkitPreBuild.GetFontScaleMode(font))
-                        effectiveStyle,
+                    {
-                        toolkitPreBuild.Scale,
+                        case FontScaleMode.Default:
-                        this.handleManager.GameFontTextureProvider,
+                        default:
-                        this.CreateTemplateFont(toolkitPreBuild, style.SizePx));
+                            plan = new(
+                                style,
+                                toolkitPreBuild.Scale,
+                                this.handleManager.GameFontTextureProvider,
+                                this.CreateTemplateFont(toolkitPreBuild, style.SizePx));
+                            break;
+
+                        case FontScaleMode.SkipHandling:
+                            plan = new(
+                                style,
+                                1f,
+                                this.handleManager.GameFontTextureProvider,
+                                this.CreateTemplateFont(toolkitPreBuild, style.SizePx));
+                            break;
+
+                        case FontScaleMode.UndoGlobalScale:
+                            plan = new(
+                                style.Scale(1 / toolkitPreBuild.Scale),
+                                toolkitPreBuild.Scale,
+                                this.handleManager.GameFontTextureProvider,
+                                this.CreateTemplateFont(toolkitPreBuild, style.SizePx));
+                            break;
+                    }
+
                     this.fonts[style] = plan;
                 }
 
@@ -620,15 +639,14 @@ internal class GamePrebakedFontHandle : FontHandle
         public unsafe void CopyGlyphsToRanges(IFontAtlasBuildToolkitPostBuild toolkitPostBuild)
         {
             var scale = this.Style.SizePt / this.Fdt.FontHeader.Size;
-            var atlasScale = toolkitPostBuild.Scale;
-            var round = 1 / atlasScale;
 
             foreach (var (font, rangeBits) in this.Ranges)
             {
                 if (font.NativePtr == this.FullRangeFont.NativePtr)
                     continue;
 
-                var noGlobalScale = toolkitPostBuild.IsGlobalScaleIgnored(font);
+                var fontScaleMode = toolkitPostBuild.GetFontScaleMode(font);
+                var round = fontScaleMode == FontScaleMode.SkipHandling ? 1 : 1 / toolkitPostBuild.Scale;
 
                 var lookup = font.IndexLookupWrapped();
                 var glyphs = font.GlyphsWrapped();
@@ -649,7 +667,7 @@ internal class GamePrebakedFontHandle : FontHandle
                     
                     ref var g = ref glyphs[glyphIndex];
                     g = sourceGlyph;
-                    if (noGlobalScale)
+                    if (fontScaleMode == FontScaleMode.SkipHandling)
                     {
                         g.XY *= scale;
                         g.AdvanceX *= scale;
@@ -673,7 +691,7 @@ internal class GamePrebakedFontHandle : FontHandle
                         continue;
                     if (!rangeBits[leftInt] || !rangeBits[rightInt])
                         continue;
-                    if (noGlobalScale)
+                    if (fontScaleMode == FontScaleMode.SkipHandling)
                     {
                         font.AddKerningPair((ushort)leftInt, (ushort)rightInt, k.RightOffset * scale);
                     }