From 11776870c4cf0c2c9d0a423a4cc597c9d0927a94 Mon Sep 17 00:00:00 2001
From: aozhiwei <aozhiwe@kingsome.cn>
Date: Wed, 10 Aug 2022 10:12:20 +0800
Subject: [PATCH] 1

---
 a8/vec2.cc | 2 +-
 a8/vec2.h  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/a8/vec2.cc b/a8/vec2.cc
index 40c064f..56ed45a 100644
--- a/a8/vec2.cc
+++ b/a8/vec2.cc
@@ -119,7 +119,7 @@ namespace a8
         return fabs(sqrt(x*x + y*y));
     }
 
-    bool Vec2::IsZero()
+    bool Vec2::IsZero() const
     {
         return fabs(x) < 0.00001f && fabs(y) < 0.00001f;
     }
diff --git a/a8/vec2.h b/a8/vec2.h
index b9ed1c8..4e6bcde 100644
--- a/a8/vec2.h
+++ b/a8/vec2.h
@@ -26,7 +26,7 @@ namespace a8
         Vec2 Perp();
         float Dot(const Vec2& v) const;
         float Norm() const;
-        bool IsZero();
+        bool IsZero() const;
 
         static const Vec2 UP;
         static const Vec2 DOWN;