diff --git a/src/main/java/cactusServer/entities/Area.java b/src/main/java/cactusServer/entities/Area.java
index 3dc0ee4..20496b4 100644
--- a/src/main/java/cactusServer/entities/Area.java
+++ b/src/main/java/cactusServer/entities/Area.java
@@ -2,25 +2,30 @@
 
 import java.util.HashSet;
 
-public class Area extends Entity{
+import framework.model3D.Position3D;
+import net.arnx.jsonic.JSONHint;
+
+public class Area extends Entity {
 	private String name;
 	private Plain[] region; // �C�ӌ‚̕��ʂ̕�����
 	private HashSet<Allowed> permissions; // �G���A���ʼn”\�Ȃ��Ƃ̗���
+	@JSONHint(ignore = true)
+	public static final int UNIQUE_ID_LENGTH = 12;
 
 	private Area() {
 		// JSONDecode���̌Ăяo���p
 	}
-	
+
 	public Area(String name, Plain[] region, HashSet<Allowed> permissions) {
 		setName(name);
 		setRegion(region);
 		setPermissions(permissions);
 	}
-	
+
 	public String getName() {
 		return name;
 	}
-	
+
 	public Plain[] getRegion() {
 		return region;
 	}
@@ -28,35 +33,47 @@
 	public Plain getRegion(int index) {
 		return region[index];
 	}
-	
+
 	public HashSet<Allowed> getPermissions() {
 		return permissions;
 	}
-	
+
 	public boolean isPermission(Allowed allowed) {
 		return permissions.contains(allowed);
 	}
 
+	public boolean isSurroundingPosition(Position3D position) {
+		for (Plain plain : region) {
+			// ������ Plain��a,b,c,d �� Character��x,y,z ��p����, �L�����N�^�[�����ʂ̗��ɂ��邩�ǂ����̔�����s��
+			double equation = (plain.getA() * position.getX()) + (plain.getB() * position.getY())
+					+ (plain.getC() * position.getZ()) + plain.getD();
+			if (equation > 0) {
+				return false;
+			}
+		}
+		return true;
+	}
+
 	public void setName(String name) {
 		this.name = name;
 	}
-	
+
 	public void setRegion(Plain[] region) {
 		this.region = region;
 	}
-	
+
 	public void setPermissions(HashSet<Allowed> permissions) {
 		this.permissions = permissions;
 	}
-	
+
 	public void addPermission(Allowed allowed) {
 		permissions.add(allowed);
 	}
-	
+
 	public void removePermission(Allowed allowed) {
 		permissions.remove(allowed);
 	}
-	
+
 	public static enum Allowed {
 		SHOOT, KILL;
 	}