added Direction2Helper.RotateBy

CHANGELOG.md

@@ -7,11 +7,15 @@ Jump to version:
 
 ## 5.1.0 (Unreleased)
 ### MLEM
+Additions
+- Added RotateBy to Direction2Helper
+
 Fixes
 - Set default values for InputHandler held and pressed keys to avoid an exception if buttons are held in the very first frame
 
 Improvements
 - Improved NinePatch memory performance
+- Moved sound-related classes into Sound namespace
 
 ### MLEM.Ui
 Fixes

MLEM/Misc/Direction2.cs

@@ -85,6 +85,9 @@ namespace MLEM.Misc {
         /// </summary>
         public static readonly Direction2[] AllExceptNone = All.Where(dir => dir != Direction2.None).ToArray();
 
+        private static readonly Direction2[] Clockwise = {Direction2.Up, Direction2.UpRight, Direction2.Right, Direction2.DownRight, Direction2.Down, Direction2.DownLeft, Direction2.Left, Direction2.UpLeft};
+        private static readonly Dictionary<Direction2, int> ClockwiseLookup = Clockwise.Select((d, i) => (d, i)).ToDictionary(kv => kv.d, kv => kv.i);
+
         /// <summary>
         /// Returns if the given direction is considered an "adjacent" direction.
         /// An adjacent direction is one that is not a diagonal.
@@ -190,26 +193,7 @@ namespace MLEM.Misc {
         /// <param name="fortyFiveDegrees">Whether to rotate by 45 degrees. If this is false, the rotation is 90 degrees instead.</param>
         /// <returns>The rotated direction</returns>
         public static Direction2 RotateCw(this Direction2 dir, bool fortyFiveDegrees = false) {
-            switch (dir) {
-                case Direction2.Up:
-                    return fortyFiveDegrees ? Direction2.UpRight : Direction2.Right;
-                case Direction2.Right:
-                    return fortyFiveDegrees ? Direction2.DownRight : Direction2.Down;
-                case Direction2.Down:
-                    return fortyFiveDegrees ? Direction2.DownLeft : Direction2.Left;
-                case Direction2.Left:
-                    return fortyFiveDegrees ? Direction2.UpLeft : Direction2.Up;
-                case Direction2.UpRight:
-                    return fortyFiveDegrees ? Direction2.Right : Direction2.DownRight;
-                case Direction2.DownRight:
-                    return fortyFiveDegrees ? Direction2.Down : Direction2.DownLeft;
-                case Direction2.DownLeft:
-                    return fortyFiveDegrees ? Direction2.Left : Direction2.UpLeft;
-                case Direction2.UpLeft:
-                    return fortyFiveDegrees ? Direction2.Up : Direction2.UpRight;
-                default:
-                    return Direction2.None;
-            }
+            return Clockwise[(ClockwiseLookup[dir] + (fortyFiveDegrees ? 1 : 2)) % Clockwise.Length];
         }
 
         /// <summary>
@@ -219,26 +203,10 @@ namespace MLEM.Misc {
         /// <param name="fortyFiveDegrees">Whether to rotate by 45 degrees. If this is false, the rotation is 90 degrees instead.</param>
         /// <returns>The rotated direction</returns>
         public static Direction2 RotateCcw(this Direction2 dir, bool fortyFiveDegrees = false) {
-            switch (dir) {
-                case Direction2.Up:
-                    return fortyFiveDegrees ? Direction2.UpLeft : Direction2.Left;
-                case Direction2.Right:
-                    return fortyFiveDegrees ? Direction2.UpRight : Direction2.Up;
-                case Direction2.Down:
-                    return fortyFiveDegrees ? Direction2.DownRight : Direction2.Right;
-                case Direction2.Left:
-                    return fortyFiveDegrees ? Direction2.DownLeft : Direction2.Down;
-                case Direction2.UpRight:
-                    return fortyFiveDegrees ? Direction2.Up : Direction2.UpLeft;
-                case Direction2.DownRight:
-                    return fortyFiveDegrees ? Direction2.Right : Direction2.UpRight;
-                case Direction2.DownLeft:
-                    return fortyFiveDegrees ? Direction2.Down : Direction2.DownRight;
-                case Direction2.UpLeft:
-                    return fortyFiveDegrees ? Direction2.Left : Direction2.DownLeft;
-                default:
-                    return Direction2.None;
-            }
+            var index = ClockwiseLookup[dir] - (fortyFiveDegrees ? 1 : 2);
+            if (index < 0)
+                index += Clockwise.Length;
+            return Clockwise[index % Clockwise.Length];
         }
 
         /// <summary>
@@ -269,5 +237,19 @@ namespace MLEM.Misc {
             return offset.Y > 0 ? Direction2.Down : Direction2.Up;
         }
 
+        /// <summary>
+        /// Rotates the given direction by a given reference direction
+        /// </summary>
+        /// <param name="dir">The direction to rotate</param>
+        /// <param name="reference">The direction to rotate by</param>
+        /// <param name="start">The direction to use as the default direction</param>
+        /// <returns>The direction, rotated by the reference direction</returns>
+        public static Direction2 RotateBy(this Direction2 dir, Direction2 reference, Direction2 start = Direction2.Up) {
+            var diff = ClockwiseLookup[reference] - ClockwiseLookup[start];
+            if (diff < 0)
+                diff += Clockwise.Length;
+            return Clockwise[(ClockwiseLookup[dir] + diff) % Clockwise.Length];
+        }
+
     }
 }

Tests/DirectionTests.cs

@@ -1,22 +1,64 @@
 using Microsoft.Xna.Framework;
 using MLEM.Misc;
 using NUnit.Framework;
+using static MLEM.Misc.Direction2;
 
 namespace Tests {
     public class DirectionTests {
 
         [Test]
         public void TestDirections() {
-            Assert.AreEqual(new Vector2(0.5F, 0.5F).ToDirection(), Direction2.DownRight);
-            Assert.AreEqual(new Vector2(0.25F, 0.5F).ToDirection(), Direction2.DownRight);
-            Assert.AreEqual(new Vector2(0.15F, 0.5F).ToDirection(), Direction2.Down);
+            Assert.AreEqual(new Vector2(0.5F, 0.5F).ToDirection(), DownRight);
+            Assert.AreEqual(new Vector2(0.25F, 0.5F).ToDirection(), DownRight);
+            Assert.AreEqual(new Vector2(0.15F, 0.5F).ToDirection(), Down);
         }
 
         [Test]
         public void Test90Directions() {
-            Assert.AreEqual(new Vector2(0.75F, 0.5F).To90Direction(), Direction2.Right);
-            Assert.AreEqual(new Vector2(0.5F, 0.5F).To90Direction(), Direction2.Down);
-            Assert.AreEqual(new Vector2(0.25F, 0.5F).To90Direction(), Direction2.Down);
+            Assert.AreEqual(new Vector2(0.75F, 0.5F).To90Direction(), Right);
+            Assert.AreEqual(new Vector2(0.5F, 0.5F).To90Direction(), Down);
+            Assert.AreEqual(new Vector2(0.25F, 0.5F).To90Direction(), Down);
+        }
+
+        [Test]
+        public void TestRotations() {
+            // rotate cw
+            Assert.AreEqual(Up.RotateCw(), Right);
+            Assert.AreEqual(Up.RotateCw(true), UpRight);
+            Assert.AreEqual(Left.RotateCw(), Up);
+            Assert.AreEqual(UpLeft.RotateCw(), UpRight);
+
+            // rotate ccw
+            Assert.AreEqual(Up.RotateCcw(), Left);
+            Assert.AreEqual(Up.RotateCcw(true), UpLeft);
+            Assert.AreEqual(Left.RotateCcw(), Down);
+            Assert.AreEqual(UpLeft.RotateCcw(), DownLeft);
+
+            // rotate 360 degrees
+            foreach (var dir in Direction2Helper.AllExceptNone) {
+                Assert.AreEqual(RotateMultipleTimes(dir, true, false, 4), dir);
+                Assert.AreEqual(RotateMultipleTimes(dir, true, true, 8), dir);
+                Assert.AreEqual(RotateMultipleTimes(dir, false, false, 4), dir);
+                Assert.AreEqual(RotateMultipleTimes(dir, false, true, 8), dir);
+            }
+
+            // rotate by with start Up
+            Assert.AreEqual(Right.RotateBy(Right), Down);
+            Assert.AreEqual(Right.RotateBy(Down), Left);
+            Assert.AreEqual(Right.RotateBy(Left), Up);
+            Assert.AreEqual(Right.RotateBy(Up), Right);
+
+            // rotate by with start Left
+            Assert.AreEqual(Up.RotateBy(Right, Left), Down);
+            Assert.AreEqual(Up.RotateBy(Down, Left), Left);
+            Assert.AreEqual(Up.RotateBy(Left, Left), Up);
+            Assert.AreEqual(Up.RotateBy(Up, Left), Right);
+        }
+
+        private static Direction2 RotateMultipleTimes(Direction2 dir, bool clockwise, bool fortyFiveDegrees, int times) {
+            for (var i = 0; i < times; i++)
+                dir = clockwise ? dir.RotateCw(fortyFiveDegrees) : dir.RotateCcw(fortyFiveDegrees);
+            return dir;
         }
 
     }