relax comparison on .NET Framework

Author: antonfirsov

tests/ImageSharp.Drawing.Tests/Drawing/DrawingRobustnessTests.cs

@@ -108,8 +108,10 @@ public void LargeGeoJson_Lines(TestImageProvider<Rgba32> provider, string geoJso
         public void LargeGeoJson_States_Fill(TestImageProvider<Rgba32> provider)
         {
             using Image<Rgba32> image = FillGeoJsonPolygons(provider, TestImages.GeoJson.States, 16, new Vector2(60), new Vector2(0, -1000));
+            ImageComparer comparer = ImageComparer.TolerantPercentage(0.001f);
+
             image.DebugSave(provider, appendPixelTypeToFileName: false, appendSourceFileOrDescription: false);
-            image.CompareToReferenceOutput(provider, appendPixelTypeToFileName: false, appendSourceFileOrDescription: false);
+            image.CompareToReferenceOutput(comparer, provider, appendPixelTypeToFileName: false, appendSourceFileOrDescription: false);
         }
 
         private Image<Rgba32> FillGeoJsonPolygons(TestImageProvider<Rgba32> provider, string geoJsonFile, int aa, Vector2 scale, Vector2 pixelOffset)
@@ -159,12 +161,17 @@ public void LargeGeoJson_Mississippi_Lines(TestImageProvider<Rgba32> provider, i
                 image.Mutate(c => c.DrawLines(Color.White, 1.0f, loop));
             }
 
-            // Very strict tolerance, since the image is sparse:
-            ImageComparer comparer = ImageComparer.TolerantPercentage(1e-7f);
+            // Very strict tolerance, since the image is sparse (relaxed on .NET Framework)
+            ImageComparer comparer = TestEnvironment.IsFramework
+                ? ImageComparer.TolerantPercentage(1e-3f)
+                : ImageComparer.TolerantPercentage(1e-7f);
+
             string details = $"PixelOffset({pixelOffset})";
             image.DebugSave(provider, details, appendPixelTypeToFileName: false, appendSourceFileOrDescription: false);
             image.CompareToReferenceOutput(comparer, provider, testOutputDetails: details, appendPixelTypeToFileName: false, appendSourceFileOrDescription: false);
         }
+        
+        
 
         [Theory(Skip = "For local experiments only")]
         [InlineData(0)]

tests/ImageSharp.Drawing.Tests/Drawing/Text/DrawTextOnImageTests.cs

@@ -25,10 +25,11 @@ public class DrawTextOnImageTests
 
         private const string TestText = "Sphinx of black quartz, judge my vow\n0123456789";
 
-        public static ImageComparer TextDrawingComparer = ImageComparer.TolerantPercentage(1e-5f);
+        public static ImageComparer TextDrawingComparer = TestEnvironment.IsFramework
+            ? ImageComparer.TolerantPercentage(1e-3f) // Relax comparison on .NET Framework 
+            : ImageComparer.TolerantPercentage(1e-5f);
+
         public static ImageComparer OutlinedTextDrawingComparer = ImageComparer.TolerantPercentage(5e-4f);
-        // public static ImageComparer TextDrawingComparer = ImageComparer.TolerantPercentage(0.1f);
-        // public static ImageComparer OutlinedTextDrawingComparer = ImageComparer.TolerantPercentage(0.2f);
 
         public DrawTextOnImageTests(ITestOutputHelper output)
         {
@@ -155,7 +156,7 @@ public void FontShapesAreRenderedCorrectly<TPixel>(
         {
             Font font = CreateFont(fontName, fontSize);
             var color = Color.Black;
-            
+
             provider.RunValidatingProcessorTest(
                 c =>
                 {

tests/ImageSharp.Drawing.Tests/Shapes/Scan/PolygonScannerTests.cs

@@ -451,7 +451,8 @@ public void NegativeOrientation01(IntersectionRule intersectionRule)
                     {
                         Empty(4f),
 
-                        (4.25f, new FuzzyFloat[] {13, 13}),
+                        // Eps = 0.01 to address inaccuracies on .NET Framework 
+                        (4.25f, new FuzzyFloat[] { F(13, 0.01f), F(13, 0.01f)}),
                         (4.5f, new FuzzyFloat[] {F(12.714286f, 0.5f), F(13.444444f, 0.5f), 16, 16}),
                         (4.75f, new FuzzyFloat[] {F(12.357143f, 0.5f), 14, 14, 16}),
                         (5f, new FuzzyFloat[] {12, 16}),
@@ -529,7 +530,6 @@ public void NumericCornerCases_Offset(float offset, string name, (float y, Fuzzy
             TestScan(poly, min, max, 4, expectedIntersections.Select(i => i.x).ToArray());
         }
 
-        
         private static (float y, FuzzyFloat[] x)[] TranslateIntersections(
             (float y, FuzzyFloat[] x)[] ex, float dx, float dy)
         {

tests/ImageSharp.Drawing.Tests/TestUtilities/FuzzyFloat.cs

@@ -11,7 +11,7 @@ namespace SixLabors.ImageSharp.Drawing.Tests.TestUtilities
     /// </summary>
     public struct FuzzyFloat : IEquatable<float>, IXunitSerializable
     {
-        public const float DefaultEpsilon = 1e-5f;
+        public static readonly float DefaultEpsilon = 1e-5f;
 
         private float value;
         private float min;

tests/ImageSharp.Drawing.Tests/TestUtilities/TestEnvironment.cs

@@ -31,12 +31,7 @@ public static partial class TestEnvironment
                     return bool.TryParse(Environment.GetEnvironmentVariable("CI"), out isCi) && isCi;
                 });
 
-        private static readonly Lazy<string> NetCoreVersionLazy = new Lazy<string>(GetNetCoreVersion);
-
-        /// <summary>
-        /// Gets the .NET Core version, if running on .NET Core, otherwise returns an empty string.
-        /// </summary>
-        internal static string NetCoreVersion => NetCoreVersionLazy.Value;
+        internal static bool IsFramework => RuntimeInformation.FrameworkDescription.StartsWith(".NET Framework");
 
         // ReSharper disable once InconsistentNaming
         /// <summary>
@@ -132,19 +127,5 @@ internal static string CreateOutputDirectory(string path, params string[] pathPa
 
             return path;
         }
-
-        /// <summary>
-        /// Solution borrowed from:
-        /// https://github.com/dotnet/BenchmarkDotNet/issues/448#issuecomment-308424100
-        /// </summary>
-        private static string GetNetCoreVersion()
-        {
-            Assembly assembly = typeof(System.Runtime.GCSettings).GetTypeInfo().Assembly;
-            string[] assemblyPath = assembly.CodeBase.Split(new[] { '/', '\\' }, StringSplitOptions.RemoveEmptyEntries);
-            int netCoreAppIndex = Array.IndexOf(assemblyPath, "Microsoft.NETCore.App");
-            if (netCoreAppIndex > 0 && netCoreAppIndex < assemblyPath.Length - 2)
-                return assemblyPath[netCoreAppIndex + 1];
-            return "";
-        }
     }
 }