diff --git a/src/common.pri b/src/common.pri
index d6543680..6b53b816 100644
--- a/src/common.pri
+++ b/src/common.pri
@@ -14,10 +14,10 @@ HEADERS += \
     $$PWD/XCAssert.h
 
 DEFINES += "AE_MAJOR_VERSION=1"
-DEFINES += "AE_MINOR_VERSION=2"
+DEFINES += "AE_MINOR_VERSION=3"
 
 DEFINES += "AE_PROJECT_FORMAT_MAJOR_VERSION=0"
-DEFINES += "AE_PROJECT_FORMAT_MINOR_VERSION=4"
+DEFINES += "AE_PROJECT_FORMAT_MINOR_VERSION=5"
 
 DEFINES += "AE_PROJECT_FORMAT_OLDEST_MAJOR_VERSION=0"
 DEFINES += "AE_PROJECT_FORMAT_OLDEST_MINOR_VERSION=4"
diff --git a/src/core/Deserializer.cpp b/src/core/Deserializer.cpp
index cca6fc9f..69926fdd 100644
--- a/src/core/Deserializer.cpp
+++ b/src/core/Deserializer.cpp
@@ -9,6 +9,7 @@ Deserializer::Deserializer(
         util::LEStreamReader& aIn,
         IDSolverType& aSolver,
         size_t aMaxFileSize,
+        QVersionNumber aVersion,
         const gl::DeviceInfo& aGLDeviceInfo,
         util::IProgressReporter& aReporter,
         int aRShiftCount)
@@ -19,6 +20,7 @@ Deserializer::Deserializer(
     , mLog()
     , mValue()
     , mMaxFileSize(aMaxFileSize)
+    , mVersion(aVersion)
     , mGLDeviceInfo(aGLDeviceInfo)
     , mReporter(aReporter)
     , mRShiftCount(aRShiftCount)
diff --git a/src/core/Deserializer.h b/src/core/Deserializer.h
index 8a8528b5..891a3c10 100644
--- a/src/core/Deserializer.h
+++ b/src/core/Deserializer.h
@@ -12,6 +12,7 @@
 #include <QMatrix4x4>
 #include <QPolygonF>
 #include <QGL>
+#include <QVersionNumber>
 #include "XC.h"
 #include "util/Segment2D.h"
 #include "util/Easing.h"
@@ -37,10 +38,13 @@ class Deserializer
             util::LEStreamReader& aIn,
             IDSolverType& aSolver,
             size_t aMaxFileSize,
+            QVersionNumber aVersion,
             const gl::DeviceInfo& aGLDeviceInfo,
             util::IProgressReporter& aRepoter,
             int aRShiftCount);
 
+    QVersionNumber version() const { return mVersion; }
+
     void read(bool& aValue);
     void read(int& aValue);
     void read(float& aValue);
@@ -124,6 +128,7 @@ class Deserializer
     QStringList mLog;
     QString mValue;
     size_t mMaxFileSize;
+    QVersionNumber mVersion;
     gl::DeviceInfo mGLDeviceInfo;
     util::IProgressReporter& mReporter;
     int mRShiftCount;
diff --git a/src/core/GridMesh.cpp b/src/core/GridMesh.cpp
index 91046d0e..068eadf7 100644
--- a/src/core/GridMesh.cpp
+++ b/src/core/GridMesh.cpp
@@ -547,6 +547,9 @@ bool GridMesh::serialize(Serializer& aOut) const
         aOut.write(XCMemBlock((uint8*)mHexaConnections.data(), connectSize));
     }
 
+    // vertex rect
+    aOut.write(mVertexRect);
+
     aOut.endBlock(pos);
 
     return !aOut.failure();
@@ -611,6 +614,28 @@ bool GridMesh::deserialize(Deserializer& aIn)
             return aIn.errored("failed to read connections");
         }
     }
+
+    // vertex rect
+    if (aIn.version() >= QVersionNumber(0, 5))
+    {
+        aIn.read(mVertexRect);
+    }
+    else
+    {
+        // note: the bug on version 0.4 or lower. mVertexRect doesn't be serialized.
+        auto positions = mPositions.data();
+        float l, t, r, b = 0.0f;
+        for (int i = 0; i < mVertexCount; ++i)
+        {
+            auto pos = positions[i];
+            l = std::min(l, pos.x - 1);
+            t = std::min(t, pos.y - 1);
+            r = std::max(r, pos.x + 1);
+            b = std::max(b, pos.y + 1);
+        }
+        mVertexRect = QRect(l, t, r - l, b - t);
+    }
+
     // initialize mesh buffer
     getMeshBuffer();
 
diff --git a/src/ctrl/ProjectLoader.cpp b/src/ctrl/ProjectLoader.cpp
index 143cab2c..18d3bad5 100644
--- a/src/ctrl/ProjectLoader.cpp
+++ b/src/ctrl/ProjectLoader.cpp
@@ -8,6 +8,7 @@ namespace ctrl
 
 ProjectLoader::ProjectLoader()
     : mLog()
+    , mVersion()
 {
 }
 
@@ -60,8 +61,8 @@ bool ProjectLoader::load(
 
     core::Deserializer::IDSolverType idSolver;
     core::Deserializer deserializer(
-                in, idSolver, maxFileSize, aGLDeviceInfo,
-                aReporter, rShiftCount);
+                in, idSolver, maxFileSize, mVersion,
+                aGLDeviceInfo, aReporter, rShiftCount);
     deserializer.reportCurrent();
 
     // resources block
@@ -144,6 +145,8 @@ bool ProjectLoader::readHeader(util::LEStreamReader& aIn)
         return false;
     }
 
+    mVersion = QVersionNumber(majorVersion, minorVersion);
+
     // reserved
     if (!aIn.skipZeroArea(16)) return false;
 
diff --git a/src/ctrl/ProjectLoader.h b/src/ctrl/ProjectLoader.h
index cb709337..7aaeeb6c 100644
--- a/src/ctrl/ProjectLoader.h
+++ b/src/ctrl/ProjectLoader.h
@@ -2,6 +2,7 @@
 #define CTRL_PROJECTLOADER_H
 
 #include <QStringList>
+#include <QVersionNumber>
 #include "util/StreamReader.h"
 #include "util/IProgressReporter.h"
 #include "gl/DeviceInfo.h"
@@ -26,6 +27,7 @@ class ProjectLoader
     bool readHeader(util::LEStreamReader& aReader);
     bool readGlobalBlock(util::LEStreamReader& aReader, core::Project& aProject);
     QStringList mLog;
+    QVersionNumber mVersion;
 };
 
 } // namespace ctrl