Add TransformationMatrix.Transform(double, double)

src/UglyToad.PdfPig.Core/TransformationMatrix.cs

@@ -28,7 +28,8 @@ public readonly struct TransformationMatrix
         /// <summary>
         /// Create a new <see cref="TransformationMatrix"/> with the X and Y scaling values set.
         /// </summary>
-        public static TransformationMatrix GetScaleMatrix(double scaleX, double scaleY) => new TransformationMatrix(scaleX, 0, 0,
+        public static TransformationMatrix GetScaleMatrix(double scaleX, double scaleY) => new TransformationMatrix(
+            scaleX, 0, 0,
             0, scaleY, 0,
             0, 0, 1);
 
@@ -84,22 +85,27 @@ public static TransformationMatrix GetRotationMatrix(double degreesCounterclockw
         /// The value at (0, 0) - The scale for the X dimension.
         /// </summary>
         public readonly double A;
+
         /// <summary>
         /// The value at (0, 1).
         /// </summary>
         public readonly double B;
+
         /// <summary>
         /// The value at (1, 0).
         /// </summary>
         public readonly double C;
+
         /// <summary>
         /// The value at (1, 1) - The scale for the Y dimension.
         /// </summary>
         public readonly double D;
+
         /// <summary>
         /// The value at (2, 0) - translation in X.
         /// </summary>
         public readonly double E;
+
         /// <summary>
         /// The value at (2, 1) - translation in Y.
         /// </summary>
@@ -223,10 +229,20 @@ public TransformationMatrix(double a, double b, double r1, double c, double d, d
         [Pure]
         public PdfPoint Transform(PdfPoint original)
         {
-            var x = A * original.X + C * original.Y + E;
-            var y = B * original.X + D * original.Y + F;
+            (double x, double y) xy = Transform(original.X, original.Y);
+            return new PdfPoint(xy.x, xy.y);
+        }
 
-            return new PdfPoint(x, y);
+        /// <summary>
+        /// Transform a point using this transformation matrix.
+        /// </summary>
+        /// <param name="x">The original point X coordinate.</param>
+        /// <param name="y">The original point Y coordinate.</param>
+        /// <returns>A new point which is the result of applying this transformation matrix.</returns>
+        [Pure]
+        public (double x, double y) Transform(double x, double y)
+        {
+            return (A * x + C * y + E, B * x + D * y + F);
         }
 
         /// <summary>
@@ -404,7 +420,7 @@ public TransformationMatrix Multiply(TransformationMatrix matrix)
             var r3 = (E * matrix.row1) + (F * matrix.row2) + (row3 * matrix.row3);
 
             return new TransformationMatrix(a, b, r1,
-                c, d, r2, 
+                c, d, r2,
                 e, f, r3);
         }