RoundToCardinalAngle

Robust.Client/GameObjects/Components/Renderable/SpriteComponent.cs

@@ -480,6 +480,8 @@ public bool SnapCardinals
         [DataField("noRot")]
         public bool NoRotation;
 
+        // TODO SPRITE
+        // When refactoring, make this nullable and remove EnableDirectionOverride
         [DataField("overrideDir")]
         public Direction DirectionOverride = Direction.East;
 

Robust.Client/GameObjects/EntitySystems/SpriteSystem.Render.cs

@@ -53,7 +53,7 @@ public void RenderSprite(
 
         // If we have a 1-directional sprite then snap it to try and always face it south if applicable.
         if (sprite.Comp is {NoRotation: false, SnapCardinals: true})
-            cardinal = angle.GetCardinalDir().ToAngle();
+            cardinal = angle.RoundToCardinalAngle();
 
         // worldRotation + eyeRotation should be the angle of the entity on-screen. If no-rot is enabled this is just set to zero.
         // However, at some point later the eye-matrix is applied separately, so we subtract -eye rotation for now:
@@ -70,14 +70,12 @@ public void RenderSprite(
             return;
         }
 
-        // TODO sprite optimize angle.GetCardinalDir().ToAngle()
-
         //Default rendering (NoRotation = false)
         entityMatrix = Matrix3Helpers.CreateTransform(worldPosition, worldRotation);
         var transformDefault = Matrix3x2.Multiply(sprite.Comp.LocalMatrix, entityMatrix);
 
         //Snap to cardinals
-        entityMatrix = Matrix3Helpers.CreateTransform(worldPosition, worldRotation - angle.GetCardinalDir().ToAngle());
+        entityMatrix = Matrix3Helpers.CreateTransform(worldPosition, worldRotation - angle.RoundToCardinalAngle());
         var transformSnap = Matrix3x2.Multiply(sprite.Comp.LocalMatrix, entityMatrix);
 
         //No rotation

Robust.Shared.Maths/Angle.cs

@@ -104,6 +104,16 @@ public readonly Direction GetCardinalDir()
             return (Direction) (Math.Floor((ang + CardinalOffset) / CardinalSegment) * 2 % 8);
         }
 
+        /// <summary>
+        /// Rounds the angle to the nearest cardinal direction. This behaves similarly to a combination of
+        /// <see cref="GetCardinalDir"/> and Direction.ToAngle(), however this may return an angle outside of the range
+        /// returned by those methods (-pi to pi).
+        /// </summary>
+        public Angle RoundToCardinalAngle()
+        {
+            return new Angle(CardinalSegment * Math.Floor((Theta + CardinalOffset) / CardinalSegment));
+        }
+
         /// <summary>
         ///     Rotates the vector counter-clockwise around its origin by the value of Theta.
         /// </summary>