Fix build, more cleanup

Author: JimBobSquarePants

src/ImageSharp.Drawing/Shapes/PolygonGeometry/Clipper.cs

@@ -6,7 +6,7 @@ namespace SixLabors.ImageSharp.Drawing.Shapes.PolygonGeometry;
 /// <summary>
 /// Defines the polygon clipping type.
 /// </summary>
-public enum ClippingType
+internal enum ClippingType
 {
     /// <summary>
     /// Represents a shape to act as a subject which will be clipped or merged.

src/ImageSharp.Drawing/Shapes/PolygonGeometry/ClippingType.cs

@@ -3,27 +3,23 @@
 
 namespace SixLabors.ImageSharp.Drawing.Shapes.PolygonGeometry;
 
+/// <summary>
+/// Specifies how a vertex should be joined with adjacent paths during polygon operations.
+/// </summary>
 internal enum JoinWith
 {
+    /// <summary>
+    /// No joining operation.
+    /// </summary>
     None,
-    Left,
-    Right
-}
 
-internal enum HorzPosition
-{
-    Bottom,
-    Middle,
-    Top
-}
+    /// <summary>
+    /// Join with the left adjacent path.
+    /// </summary>
+    Left,
 
-// Vertex: a pre-clipping data structure. It is used to separate polygons
-// into ascending and descending 'bounds' (or sides) that start at local
-// minima and ascend to a local maxima, before descending again.
-[Flags]
-internal enum PointInPolygonResult
-{
-    IsOn = 0,
-    IsInside = 1,
-    IsOutside = 2
+    /// <summary>
+    /// Join with the right adjacent path.
+    /// </summary>
+    Right
 }

src/ImageSharp.Drawing/Shapes/PolygonGeometry/JoinWith.cs

@@ -1024,7 +1024,7 @@ private void DoSplitOp(OutRec outrec, OutPt splitOp)
         OutPt nextNextOp = splitOp.Next.Next;
         outrec.Pts = prevOp;
 
-        PolygonClipperUtilities.GetIntersectPoint(
+        _ = PolygonClipperUtilities.GetLineIntersectPoint(
             prevOp.Point, splitOp.Point, splitOp.Next.Point, nextNextOp.Point, out Vector2 ip);
 
         float area1 = Area(prevOp);