Merge pull request #32 from SixLabors/js/remove-inner-join

Remove InnerJoin and InnerMiterLimit support

Author: JimBobSquarePants

README.md

@@ -61,7 +61,6 @@ StrokeOptions options = new()
     LineJoin = LineJoin.Round,
     LineCap = LineCap.Round,
     MiterLimit = 4,
-    InnerMiterLimit = 1.01,
     ArcDetailScale = 1
 };
 

src/PolygonClipper/InnerJoin.cs

@@ -36,6 +36,9 @@ public sealed class PolygonStroker
     private const double Pi = Math.PI;
     private const double PiMul2 = Math.PI * 2D;
 
+    // The inner miter limit used to clamp joins on acute interior angles.
+    private const double InnerMiterLimit = 1.01D;
+
     // Keep at most 2 warm instances per option-set (one active shape and one spare)
     // to reduce churn without retaining many rarely reused configurations.
     private const int MaxPooledStrokersPerOptions = 2;
@@ -79,10 +82,8 @@ public PolygonStroker(StrokeOptions options)
         ArgumentNullException.ThrowIfNull(options);
         this.NormalizeOutput = options.NormalizeOutput;
         this.LineJoin = options.LineJoin;
-        this.InnerJoin = options.InnerJoin;
         this.LineCap = options.LineCap;
         this.MiterLimit = options.MiterLimit;
-        this.InnerMiterLimit = options.InnerMiterLimit;
         this.ArcDetailScale = options.ArcDetailScale;
     }
 
@@ -131,34 +132,26 @@ public StrokeOptionsKey(StrokeOptions options)
         {
             this.NormalizeOutput = options.NormalizeOutput;
             this.LineJoin = options.LineJoin;
-            this.InnerJoin = options.InnerJoin;
             this.LineCap = options.LineCap;
             this.MiterLimit = options.MiterLimit;
-            this.InnerMiterLimit = options.InnerMiterLimit;
             this.ArcDetailScale = options.ArcDetailScale;
         }
 
         public bool NormalizeOutput { get; }
 
         public LineJoin LineJoin { get; }
 
-        public InnerJoin InnerJoin { get; }
-
         public LineCap LineCap { get; }
 
         public double MiterLimit { get; }
 
-        public double InnerMiterLimit { get; }
-
         public double ArcDetailScale { get; }
 
         public bool Equals(StrokeOptionsKey other)
             => this.NormalizeOutput == other.NormalizeOutput &&
                this.LineJoin == other.LineJoin &&
-               this.InnerJoin == other.InnerJoin &&
                this.LineCap == other.LineCap &&
                this.MiterLimit == other.MiterLimit &&
-               this.InnerMiterLimit == other.InnerMiterLimit &&
                this.ArcDetailScale == other.ArcDetailScale;
 
         public override bool Equals(object? obj) => obj is StrokeOptionsKey other && this.Equals(other);
@@ -167,10 +160,8 @@ public override int GetHashCode()
             => HashCode.Combine(
                 this.NormalizeOutput,
                 this.LineJoin,
-                this.InnerJoin,
                 this.LineCap,
                 this.MiterLimit,
-                this.InnerMiterLimit,
                 this.ArcDetailScale);
     }
 
@@ -266,11 +257,6 @@ public Polygon Stroke(Polygon polygon, double width)
     /// </summary>
     public double MiterLimit { get; }
 
-    /// <summary>
-    /// Gets the inner miter limit used to clamp joins on acute interior angles.
-    /// </summary>
-    public double InnerMiterLimit { get; }
-
     /// <summary>
     /// Gets the tessellation detail scale used for round joins and round caps.
     /// Higher values produce more vertices and smoother curves.
@@ -287,11 +273,6 @@ public Polygon Stroke(Polygon polygon, double width)
     /// </summary>
     public LineCap LineCap { get; }
 
-    /// <summary>
-    /// Gets the join style used for sharp interior angles.
-    /// </summary>
-    public InnerJoin InnerJoin { get; }
-
     /// <summary>
     /// Gets a value indicating whether generated contours should be normalized by resolving
     /// self-intersections and overlaps.
@@ -1123,52 +1104,12 @@ private void CalcJoin(ref StrokeVertexDistance v0, ref StrokeVertexDistance v1,
         if (Math.Abs(cp) > double.Epsilon && (cp > 0D) == (strokeWidth > 0D))
         {
             double limit = Math.Min(len1, len2) / widthAbs;
-            if (limit < this.InnerMiterLimit)
+            if (limit < InnerMiterLimit)
             {
-                limit = this.InnerMiterLimit;
+                limit = InnerMiterLimit;
             }
 
-            switch (this.InnerJoin)
-            {
-                default:
-                    // Bevel-like fallback for inner corners.
-                    this.AddPoint(v1.X + dx1, v1.Y - dy1);
-                    this.AddPoint(v1.X + dx2, v1.Y - dy2);
-                    break;
-
-                case InnerJoin.Miter:
-                    this.CalcMiter(ref v0, ref v1, ref v2, dx1, dy1, dx2, dy2, LineJoin.MiterRevert, limit, 0D);
-                    break;
-
-                case InnerJoin.Jag:
-                case InnerJoin.Round:
-                    // If offsets are close enough, miter produces cleaner inner-corner output.
-                    Vertex offset1 = new(dx1, dy1);
-                    Vertex offset2 = new(dx2, dy2);
-                    double offsetDeltaSquared = Vertex.DistanceSquared(offset1, offset2);
-                    if (offsetDeltaSquared < len1 * len1 && offsetDeltaSquared < len2 * len2)
-                    {
-                        this.CalcMiter(ref v0, ref v1, ref v2, dx1, dy1, dx2, dy2, LineJoin.MiterRevert, limit, 0D);
-                    }
-                    else if (this.InnerJoin == InnerJoin.Jag)
-                    {
-                        // Jagged inner join inserts center vertex to preserve cusp.
-                        this.AddPoint(v1.X + dx1, v1.Y - dy1);
-                        this.AddPoint(v1.X, v1.Y);
-                        this.AddPoint(v1.X + dx2, v1.Y - dy2);
-                    }
-                    else
-                    {
-                        // Rounded inner join bridges via arc passing through the corner.
-                        this.AddPoint(v1.X + dx1, v1.Y - dy1);
-                        this.AddPoint(v1.X, v1.Y);
-                        this.CalcArc(v1.X, v1.Y, dx2, -dy2, dx1, -dy1);
-                        this.AddPoint(v1.X, v1.Y);
-                        this.AddPoint(v1.X + dx2, v1.Y - dy2);
-                    }
-
-                    break;
-            }
+            this.CalcMiter(ref v0, ref v1, ref v2, dx1, dy1, dx2, dy2, LineJoin.MiterRevert, limit, 0D);
         }
         else
         {

src/PolygonClipper/PolygonStroker.cs

@@ -23,11 +23,6 @@ public sealed class StrokeOptions : IEquatable<StrokeOptions?>
     /// </summary>
     public double MiterLimit { get; set; } = 4D;
 
-    /// <summary>
-    /// Gets or sets the inner miter limit used to clamp joins on acute interior angles.
-    /// </summary>
-    public double InnerMiterLimit { get; set; } = 1.01D;
-
     /// <summary>
     /// Gets or sets the tessellation detail scale for round joins and round caps.
     /// Higher values produce more vertices (smoother curves, more work).
@@ -45,11 +40,6 @@ public sealed class StrokeOptions : IEquatable<StrokeOptions?>
     /// </summary>
     public LineCap LineCap { get; set; } = LineCap.Butt;
 
-    /// <summary>
-    /// Gets or sets the join style used for sharp interior angles.
-    /// </summary>
-    public InnerJoin InnerJoin { get; set; } = InnerJoin.Miter;
-
     /// <inheritdoc/>
     public override bool Equals(object? obj) => this.Equals(obj as StrokeOptions);
 
@@ -58,20 +48,16 @@ public bool Equals(StrokeOptions? other)
         => other is not null &&
            this.NormalizeOutput == other.NormalizeOutput &&
            this.MiterLimit == other.MiterLimit &&
-           this.InnerMiterLimit == other.InnerMiterLimit &&
            this.ArcDetailScale == other.ArcDetailScale &&
            this.LineJoin == other.LineJoin &&
-           this.LineCap == other.LineCap &&
-           this.InnerJoin == other.InnerJoin;
+           this.LineCap == other.LineCap;
 
     /// <inheritdoc/>
     public override int GetHashCode()
         => HashCode.Combine(
             this.NormalizeOutput,
             this.MiterLimit,
-            this.InnerMiterLimit,
             this.ArcDetailScale,
             this.LineJoin,
-            this.LineCap,
-            this.InnerJoin);
+            this.LineCap);
 }

src/PolygonClipper/StrokeOptions.cs

@@ -68,8 +68,7 @@ public void Stroke_OpenPolylineWithThreeVertices_IsNotForcedClosed()
         StrokeOptions options = new()
         {
             LineCap = LineCap.Butt,
-            LineJoin = LineJoin.Miter,
-            InnerJoin = InnerJoin.Miter
+            LineJoin = LineJoin.Miter
         };
 
         Polygon open =
@@ -138,7 +137,7 @@ public void ProcessPolygonAndClip_FigureNinePath_ProducesValidStroke()
         AssertStrokeCoversInputCenterline(input, actual, samplesPerSegment: 3);
     }
 
-    [Theory (Skip = "For profiling only.")]
+    [Theory(Skip = "For profiling only.")]
     [InlineData(101)]
     [InlineData(301)]
     [InlineData(1001)]