diff --git a/Assets/Shaders/SnapGrid3D.shader b/Assets/Shaders/SnapGrid3D.shader
index a43ce07c0b..1c5984e3a0 100644
--- a/Assets/Shaders/SnapGrid3D.shader
+++ b/Assets/Shaders/SnapGrid3D.shader
@@ -1,4 +1,4 @@
-// Upgrade NOTE: replaced '_Object2World' with 'unity_ObjectToWorld'
+// Upgrade NOTE: replaced '_Object2World' with 'unity_ObjectToWorld'
 // MIT License
 //
 // Copyright (c) 2020 fuqunaga
@@ -148,16 +148,16 @@ Shader "Custom/Grid3D"
                 float3 _Pointer_CS = mul(_WorldToCanvasMatrix, _Pointer_GS);
                 
                 float3 quantizedPointer_CS = float3(
-                    round(_Pointer_CS.x / _GridInterval) * _GridInterval,
-                    round(_Pointer_CS.y / _GridInterval) * _GridInterval,
-                    round(_Pointer_CS.z / _GridInterval) * _GridInterval
+                    round((_Pointer_CS.x + _GridInterval * 0.5) / _GridInterval) * _GridInterval,
+                    round((_Pointer_CS.y + _GridInterval * 0.5) / _GridInterval) * _GridInterval,
+                    round((_Pointer_CS.z + _GridInterval * 0.5) / _GridInterval) * _GridInterval
                 );
 
                 float3 _CanvasOrigin_CS = mul(_WorldToCanvasMatrix, _CanvasOrigin_GS);
                 float3 quantizedCanvasOrigin_CS = float3(
-                    round(_CanvasOrigin_CS.x / _GridInterval) * _GridInterval,
-                    round(_CanvasOrigin_CS.y / _GridInterval) * _GridInterval,
-                    round(_CanvasOrigin_CS.z / _GridInterval) * _GridInterval
+                    round((_CanvasOrigin_CS.x + _GridInterval * 0.5) / _GridInterval) * _GridInterval,
+                    round((_CanvasOrigin_CS.y + _GridInterval * 0.5) / _GridInterval) * _GridInterval,
+                    round((_CanvasOrigin_CS.z + _GridInterval * 0.5) / _GridInterval) * _GridInterval
                 );
                 float3 canvasOffsetFix_CS = quantizedCanvasOrigin_CS - _CanvasOrigin_CS;
                 float3 canvasOffsetFix_GS = mul(_CanvasToWorldMatrix, canvasOffsetFix_CS);