Add frost barrier spell

src/main/java/electroblob/wizardry/util/GeometryUtils.java

@@ -100,6 +100,13 @@ public final class GeometryUtils {
 		return new Vec3i(components[0], components[1], components[2]);
 	}
 
+	/**
+	 * Returns a normalised {@link Vec3d} with the same yaw angle as the given vector, but with a y component of zero.
+	 */
+	public static Vec3d horizontalise(Vec3d vec){
+		return replaceComponent(vec, Axis.Y, 0).normalize();
+	}
+
 	/**
 	 * Returns an array of {@code Vec3d} objects representing the vertices of the given bounding box.
 	 * @param box The bounding box whose vertices are to be returned.

src/main/java/electroblob/wizardry/util/SpellModifiers.java

@@ -58,20 +58,15 @@ public final class SpellModifiers {
 		syncedMultiplierMap = new HashMap<>();
 	}
 
-//	/** Returns a deep copy of this {@code SpellModifiers} object. */
-//	@Override
-//	public SpellModifiers clone(){
-//		SpellModifiers clone;
-//		try {
-//			clone = (SpellModifiers)super.clone();
-//		}catch(CloneNotSupportedException e){
-//			Wizardry.logger.error("Whaaaaat?!", e);
-//			return null;
-//		}
-//		clone.multiplierMap = new HashMap<>(this.multiplierMap);
-//		clone.syncedMultiplierMap = new HashMap<>(this.syncedMultiplierMap);
-//		return clone;
-//	}
+	private SpellModifiers(Map<String, Float> multiplierMap, Map<String, Float> syncedMultiplierMap){
+		this.multiplierMap = multiplierMap;
+		this.syncedMultiplierMap = syncedMultiplierMap;
+	}
+
+	/** Returns a deep copy (with copies of the underlying maps) of this {@code SpellModifiers} object. */
+	public SpellModifiers copy(){
+		return new SpellModifiers(new HashMap<>(this.multiplierMap), new HashMap<>(this.syncedMultiplierMap));
+	}
 
 	/**
 	 * Adds the given multiplier to this SpellModifiers object, using the string identifier that the given wand upgrade