Replace DirectionUtil methods with builtin equivalents

src/main/java/dan200/computercraft/client/render/TileEntityMonitorRenderer.java

@@ -70,7 +70,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
         // Determine orientation
         EnumFacing dir = origin.getDirection();
         EnumFacing front = origin.getFront();
-        float yaw = DirectionUtil.toYawAngle( dir );
+        float yaw = dir.getHorizontalAngle();
         float pitch = DirectionUtil.toPitchAngle( front );
 
         GlStateManager.pushMatrix();

src/main/java/dan200/computercraft/shared/turtle/core/TurtleBrain.java

@@ -610,7 +610,7 @@ public class TurtleBrain implements ITurtleAccess
     @Override
     public float getVisualYaw( float f )
     {
-        float yaw = DirectionUtil.toYawAngle( getDirection() );
+        float yaw = getDirection().getHorizontalAngle();
         switch( m_animation )
         {
             case TurnLeft:

src/main/java/dan200/computercraft/shared/turtle/core/TurtlePlaceCommand.java

@@ -194,12 +194,12 @@ public class TurtlePlaceCommand implements ITurtleCommand
 
         if( direction.getAxis() != EnumFacing.Axis.Y )
         {
-            turtlePlayer.rotationYaw = DirectionUtil.toYawAngle( direction );
+            turtlePlayer.rotationYaw = direction.getHorizontalAngle();
             turtlePlayer.rotationPitch = 0.0f;
         }
         else
         {
-            turtlePlayer.rotationYaw = DirectionUtil.toYawAngle( turtle.getDirection() );
+            turtlePlayer.rotationYaw = turtle.getDirection().getHorizontalAngle();
             turtlePlayer.rotationPitch = DirectionUtil.toPitchAngle( direction );
         }
 

src/main/java/dan200/computercraft/shared/turtle/core/TurtleTurnCommand.java

@@ -12,7 +12,6 @@ import dan200.computercraft.api.turtle.TurtleAnimation;
 import dan200.computercraft.api.turtle.TurtleCommandResult;
 import dan200.computercraft.api.turtle.event.TurtleAction;
 import dan200.computercraft.api.turtle.event.TurtleActionEvent;
-import dan200.computercraft.shared.util.DirectionUtil;
 import net.minecraftforge.common.MinecraftForge;
 
 import javax.annotation.Nonnull;
@@ -40,13 +39,13 @@ public class TurtleTurnCommand implements ITurtleCommand
         {
             case Left:
             {
-                turtle.setDirection( DirectionUtil.rotateLeft( turtle.getDirection() ) );
+                turtle.setDirection( turtle.getDirection().rotateYCCW() );
                 turtle.playAnimation( TurtleAnimation.TurnLeft );
                 return TurtleCommandResult.success();
             }
             case Right:
             {
-                turtle.setDirection( DirectionUtil.rotateRight( turtle.getDirection() ) );
+                turtle.setDirection( turtle.getDirection().rotateY() );
                 turtle.playAnimation( TurtleAnimation.TurnRight );
                 return TurtleCommandResult.success();
             }

src/main/java/dan200/computercraft/shared/util/DirectionUtil.java

@@ -9,57 +9,17 @@ package dan200.computercraft.shared.util;
 import dan200.computercraft.shared.common.IDirectionalTile;
 import net.minecraft.entity.EntityLivingBase;
 import net.minecraft.util.EnumFacing;
-import net.minecraft.util.math.MathHelper;
 
 public class DirectionUtil
 {
-    public static EnumFacing rotateRight( EnumFacing dir )
-    {
-        if( dir.getAxis() != EnumFacing.Axis.Y )
-        {
-            return dir.rotateY();
-        }
-        else
-        {
-            return dir;
-        }
-    }
-
-    public static EnumFacing rotateLeft( EnumFacing dir )
-    {
-        if( dir.getAxis() != EnumFacing.Axis.Y )
-        {
-            return dir.rotateYCCW();
-        }
-        else
-        {
-            return dir;
-        }
-    }
-
-    public static EnumFacing rotate180( EnumFacing dir )
-    {
-        if( dir.getAxis() != EnumFacing.Axis.Y )
-        {
-            return dir.getOpposite();
-        }
-        else
-        {
-            return dir;
-        }
-    }
-
     public static int toLocal( IDirectionalTile directional, EnumFacing dir )
     {
         EnumFacing front = directional.getDirection();
-        if( front.getAxis() == EnumFacing.Axis.Y )
+        if( front.getAxis() == EnumFacing.Axis.Y ) front = EnumFacing.NORTH;
-        {
-            front = EnumFacing.NORTH;
-        }
 
-        EnumFacing back = rotate180( front );
+        EnumFacing back = front.getOpposite();
-        EnumFacing left = rotateLeft( front );
+        EnumFacing left = front.rotateYCCW();
-        EnumFacing right = rotateRight( front );
+        EnumFacing right = front.rotateY();
         if( dir == front )
         {
             return 3;
@@ -88,36 +48,7 @@ public class DirectionUtil
 
     public static EnumFacing fromEntityRot( EntityLivingBase player )
     {
-        int rot = MathHelper.floor( (player.rotationYaw / 90.0f) + 0.5f ) & 0x3;
+        return EnumFacing.fromAngle( player.rotationYaw ).getOpposite();
-        switch( rot )
-        {
-            case 0:
-                return EnumFacing.NORTH;
-            case 1:
-                return EnumFacing.EAST;
-            case 2:
-                return EnumFacing.SOUTH;
-            case 3:
-                return EnumFacing.WEST;
-        }
-        return EnumFacing.NORTH;
-    }
-
-    public static float toYawAngle( EnumFacing dir )
-    {
-        switch( dir )
-        {
-            case NORTH:
-                return 180.0f;
-            case SOUTH:
-                return 0.0f;
-            case WEST:
-                return 90.0f;
-            case EAST:
-                return 270.0f;
-            default:
-                return 0.0f;
-        }
     }
 
     public static float toPitchAngle( EnumFacing dir )