feat: Dynamic Runtime Rasterized MSDF Sprite Font

sources/Directory.Packages.props

@@ -14,7 +14,9 @@
     <PackageVersion Include="Microsoft.Management.Infrastructure" Version="3.0.0-preview.4" />
     <PackageVersion Include="Microsoft.NETCore.Platforms" Version="7.0.4" />
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
+    <PackageVersion Include="MSDF-Sharp.Core" Version="1.0.2" />
     <PackageVersion Include="PolySharp" Version="1.15.0" />
+    <PackageVersion Include="Remora.MSDFGen" Version="1.0.0" />
     <PackageVersion Include="ServiceWire" Version="5.6.0" />
     <PackageVersion Include="SharpDX" Version="4.2.0" />
     <PackageVersion Include="SharpDX.D3DCompiler" Version="4.2.0" />
@@ -123,4 +125,4 @@
     <PackageVersion Include="Microsoft.CodeAnalysis.Analyzers" Version="3.11.0" PrivateAssets="all" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.14.0" PrivateAssets="all" />
   </ItemGroup>
-</Project>
+</Project>

sources/engine/Stride.Assets/SpriteFont/RuntimeSignedDistanceFieldSpriteFontType.cs

@@ -0,0 +1,40 @@
+// Copyright (c) .NET Foundation and Contributors (https://dotnetfoundation.org/ & https://stride3d.net)
+// Distributed under the MIT license. See the LICENSE.md file in the project root for more information.
+
+using System.ComponentModel;
+using Stride.Core;
+using Stride.Core.Annotations;
+using Stride.Core.Mathematics;
+
+namespace Stride.Assets.SpriteFont
+{
+    [DataContract("RuntimeSignedDistanceFieldSpriteFontType")]
+    [Display("Runtime SDF")]
+    public class RuntimeSignedDistanceFieldSpriteFontType : SpriteFontTypeBase
+    {
+        /// <inheritdoc/>
+        [DataMember(30)]
+        [DataMemberRange(MathUtil.ZeroTolerance, 2)]
+        [DefaultValue(20)]
+        [Display("Default Size")]
+        public override float Size { get; set; } = 64;
+
+        /// <summary>
+        /// Distance field range/spread (in pixels) used during MSDF generation.
+        /// </summary>
+        [DataMember(40)]
+        [DefaultValue(8)]
+        [DataMemberRange(1, 64, 1, 4, 0)]
+        [Display("Pixel Range")]
+        public int PixelRange { get; set; } = 8;
+
+        /// <summary>
+        /// Extra padding around each glyph inside the atlas (in pixels).
+        /// </summary>
+        [DataMember(50)]
+        [DefaultValue(2)]
+        [DataMemberRange(0, 16, 1, 2, 0)]
+        [Display("Padding")]
+        public int Padding { get; set; } = 2;
+    }
+}

sources/engine/Stride.Assets/SpriteFont/SpriteFontAssetCompiler.cs

@@ -28,8 +28,7 @@ protected override void Prepare(AssetCompilerContext context, AssetItem assetIte
             UFile assetAbsolutePath = assetItem.FullPath;
             var colorSpace = context.GetColorSpace();
 
-            var fontTypeSdf = asset.FontType as SignedDistanceFieldSpriteFontType;
-            if (fontTypeSdf != null)
+            if (asset.FontType is SignedDistanceFieldSpriteFontType fontTypeSdf)
             {
                 // copy the asset and transform the source and character set file path to absolute paths
                 var assetClone = AssetCloner.Clone(asset);
@@ -40,39 +39,54 @@ protected override void Prepare(AssetCompilerContext context, AssetItem assetIte
                 result.BuildSteps = new AssetBuildStep(assetItem);
                 result.BuildSteps.Add(new SignedDistanceFieldFontCommand(targetUrlInStorage, assetClone, assetItem.Package));
             }
-            else
-                if (asset.FontType is RuntimeRasterizedSpriteFontType)
+            else if (asset.FontType is RuntimeRasterizedSpriteFontType)
+            {
+                UFile fontPathOnDisk = asset.FontSource.GetFontPath(result);
+                if (fontPathOnDisk == null)
                 {
-                    UFile fontPathOnDisk = asset.FontSource.GetFontPath(result);
-                    if (fontPathOnDisk == null)
-                    {
-                        result.Error($"Runtime rasterized font compilation failed. Font {asset.FontSource.GetFontName()} was not found on this machine.");
-                        result.BuildSteps = new AssetBuildStep(assetItem);
-                        result.BuildSteps.Add(new FailedFontCommand());
-                        return;
-                    }
-
-                    var fontImportLocation = FontHelper.GetFontPath(asset.FontSource.GetFontName(), asset.FontSource.Style);
-
+                    result.Error($"Runtime rasterized font compilation failed. Font {asset.FontSource.GetFontName()} was not found on this machine.");
                     result.BuildSteps = new AssetBuildStep(assetItem);
-                    result.BuildSteps.Add(new ImportStreamCommand { SourcePath = fontPathOnDisk, Location = fontImportLocation });
-                    result.BuildSteps.Add(new RuntimeRasterizedFontCommand(targetUrlInStorage, asset, assetItem.Package));
+                    result.BuildSteps.Add(new FailedFontCommand());
+                    return;
                 }
-                else
-                {
-                    var fontTypeStatic = asset.FontType as OfflineRasterizedSpriteFontType;
-                    if (fontTypeStatic == null)
-                        throw new ArgumentException("Tried to compile a non-offline rasterized sprite font with the compiler for offline resterized fonts!");
 
-                    // copy the asset and transform the source and character set file path to absolute paths
-                    var assetClone = AssetCloner.Clone(asset);
-                    var assetDirectory = assetAbsolutePath.GetParent();
-                    assetClone.FontSource = asset.FontSource;
-                    fontTypeStatic.CharacterSet = !string.IsNullOrEmpty(fontTypeStatic.CharacterSet) ? UPath.Combine(assetDirectory, fontTypeStatic.CharacterSet): null;
+                var fontImportLocation = FontHelper.GetFontPath(asset.FontSource.GetFontName(), asset.FontSource.Style);
 
+                result.BuildSteps = new AssetBuildStep(assetItem);
+                result.BuildSteps.Add(new ImportStreamCommand { SourcePath = fontPathOnDisk, Location = fontImportLocation });
+                result.BuildSteps.Add(new RuntimeRasterizedFontCommand(targetUrlInStorage, asset, assetItem.Package));
+            }
+            else if (asset.FontType is RuntimeSignedDistanceFieldSpriteFontType)
+            {
+                UFile fontPathOnDisk = asset.FontSource.GetFontPath(result);
+                if (fontPathOnDisk == null)
+                {
+                    result.Error($"Runtime SDF font compilation failed. Font {asset.FontSource.GetFontName()} was not found on this machine.");
                     result.BuildSteps = new AssetBuildStep(assetItem);
-                    result.BuildSteps.Add(new OfflineRasterizedFontCommand(targetUrlInStorage, assetClone, colorSpace, assetItem.Package));
+                    result.BuildSteps.Add(new FailedFontCommand());
+                    return;
                 }
+
+                var fontImportLocation = FontHelper.GetFontPath(asset.FontSource.GetFontName(), asset.FontSource.Style);
+
+                result.BuildSteps = new AssetBuildStep(assetItem);
+                result.BuildSteps.Add(new ImportStreamCommand { SourcePath = fontPathOnDisk, Location = fontImportLocation });
+                result.BuildSteps.Add(new RuntimeSignedDistanceFieldFontCommand(targetUrlInStorage, asset, assetItem.Package));
+            }
+            else
+            {
+                if (asset.FontType is not OfflineRasterizedSpriteFontType fontTypeStatic)
+                    throw new ArgumentException("Tried to compile a non-offline rasterized sprite font with the compiler for offline resterized fonts!");
+
+                // copy the asset and transform the source and character set file path to absolute paths
+                var assetClone = AssetCloner.Clone(asset);
+                var assetDirectory = assetAbsolutePath.GetParent();
+                assetClone.FontSource = asset.FontSource;
+                fontTypeStatic.CharacterSet = !string.IsNullOrEmpty(fontTypeStatic.CharacterSet) ? UPath.Combine(assetDirectory, fontTypeStatic.CharacterSet) : null;
+
+                result.BuildSteps = new AssetBuildStep(assetItem);
+                result.BuildSteps.Add(new OfflineRasterizedFontCommand(targetUrlInStorage, assetClone, colorSpace, assetItem.Package));
+            }
         }
 
         internal class OfflineRasterizedFontCommand : AssetCommand<SpriteFontAsset>
@@ -88,15 +102,13 @@ public OfflineRasterizedFontCommand(string url, SpriteFontAsset description, Col
             public override IEnumerable<ObjectUrl> GetInputFiles()
             {
                 var asset = Parameters;
-                var fontTypeStatic = asset.FontType as OfflineRasterizedSpriteFontType;
-                if (fontTypeStatic != null)
+                if (asset.FontType is OfflineRasterizedSpriteFontType fontTypeStatic)
                 {
                     if (File.Exists(fontTypeStatic.CharacterSet))
                         yield return new ObjectUrl(UrlType.File, fontTypeStatic.CharacterSet);
                 }
 
-                var fontTypeSdf = asset.FontType as SignedDistanceFieldSpriteFontType;
-                if (fontTypeSdf != null)
+                if (asset.FontType is SignedDistanceFieldSpriteFontType fontTypeSdf)
                 {
                     if (File.Exists(fontTypeSdf.CharacterSet))
                         yield return new ObjectUrl(UrlType.File, fontTypeSdf.CharacterSet);
@@ -118,7 +130,7 @@ protected override Task<ResultStatus> DoCommandOverride(ICommandContext commandC
                 {
                     staticFont = OfflineRasterizedFontCompiler.Compile(FontDataFactory, Parameters, colorspace == ColorSpace.Linear);
                 }
-                catch (FontNotFoundException ex) 
+                catch (FontNotFoundException ex)
                 {
                     commandContext.Logger.Error($"Font [{ex.FontName}] was not found on this machine.", ex);
                     return Task.FromResult(ResultStatus.Failed);
@@ -190,9 +202,9 @@ public RuntimeRasterizedFontCommand(string url, SpriteFontAsset description, IAs
             protected override Task<ResultStatus> DoCommandOverride(ICommandContext commandContext)
             {
                 var dynamicFont = FontDataFactory.NewDynamic(
-                    Parameters.FontType.Size, Parameters.FontSource.GetFontName(), Parameters.FontSource.Style, 
-                    Parameters.FontType.AntiAlias, useKerning:false, extraSpacing:Parameters.Spacing, extraLineSpacing:Parameters.LineSpacing, 
-                    defaultCharacter:Parameters.DefaultCharacter);
+                    Parameters.FontType.Size, Parameters.FontSource.GetFontName(), Parameters.FontSource.Style,
+                    Parameters.FontType.AntiAlias, useKerning: false, extraSpacing: Parameters.Spacing, extraLineSpacing: Parameters.LineSpacing,
+                    defaultCharacter: Parameters.DefaultCharacter);
 
                 var assetManager = new ContentManager(MicrothreadLocalDatabases.ProviderService);
                 assetManager.Save(Url, dynamicFont);
@@ -201,6 +213,37 @@ protected override Task<ResultStatus> DoCommandOverride(ICommandContext commandC
             }
         }
 
+        internal class RuntimeSignedDistanceFieldFontCommand : AssetCommand<SpriteFontAsset>
+        {
+            public RuntimeSignedDistanceFieldFontCommand(string url, SpriteFontAsset description, IAssetFinder assetFinder)
+                : base(url, description, assetFinder)
+            {
+            }
+
+            protected override Task<ResultStatus> DoCommandOverride(ICommandContext commandContext)
+            {
+                commandContext.Logger.Warning("Runtime SDF font is currently an experimental feature.");
+
+                var runtimeSdfType = (RuntimeSignedDistanceFieldSpriteFontType)Parameters.FontType;
+
+                var sdfFont = FontDataFactory.NewRuntimeSignedDistanceField(
+                    runtimeSdfType.Size,
+                    Parameters.FontSource.GetFontName(),
+                    Parameters.FontSource.Style,
+                    runtimeSdfType.PixelRange,
+                    runtimeSdfType.Padding,
+                    useKerning: false,
+                    extraSpacing: Parameters.Spacing,
+                    extraLineSpacing: Parameters.LineSpacing,
+                    defaultCharacter: Parameters.DefaultCharacter);
+
+                var assetManager = new ContentManager(MicrothreadLocalDatabases.ProviderService);
+                assetManager.Save(Url, sdfFont);
+
+                return Task.FromResult(ResultStatus.Successful);
+            }
+        }
+
         /// <summary>
         /// Proxy command which always fails, called when font is compiled with the wrong assets
         /// </summary>

sources/engine/Stride.Assets/SpriteFont/SpriteFontAssetFactories.cs

@@ -14,7 +14,7 @@ public static SpriteFontAsset Create()
                 FontSource = new SystemFontProvider(),
                 FontType = new OfflineRasterizedSpriteFontType()
                 {
-                    CharacterRegions = { new CharacterRegion(' ', (char)127) }                 
+                    CharacterRegions = { new CharacterRegion(' ', (char)127) }
                 },
             };
         }
@@ -42,7 +42,7 @@ public override SpriteFontAsset New()
         }
     }
 
-    public class SignedDistanceFieldSpriteFontFactory: AssetFactory<SpriteFontAsset>
+    public class SignedDistanceFieldSpriteFontFactory : AssetFactory<SpriteFontAsset>
     {
         public static SpriteFontAsset Create()
         {
@@ -61,4 +61,21 @@ public override SpriteFontAsset New()
             return Create();
         }
     }
+
+    public class RuntimeSignedDistanceFieldSpriteFontFactory : AssetFactory<SpriteFontAsset>
+    {
+        public static SpriteFontAsset Create()
+        {
+            return new SpriteFontAsset
+            {
+                FontSource = new SystemFontProvider(),
+                FontType = new RuntimeSignedDistanceFieldSpriteFontType(),
+            };
+        }
+
+        public override SpriteFontAsset New()
+        {
+            return Create();
+        }
+    }
 }