math/box2.h: normalize on construction, minor compilation warning fix

include/math/box2.h

@@ -66,7 +66,9 @@ public:
     BOX2( const Vec& aPos, const Vec& aSize ) :
         m_Pos( aPos ),
         m_Size( aSize )
-    { }
+    { 
+        Normalize();
+	}
 
     void SetMaximum()
     {
@@ -416,8 +418,8 @@ public:
     {
         ecoord_type x2 = m_Pos.x + m_Size.x;
         ecoord_type y2 = m_Pos.y + m_Size.y;
-        ecoord_type xdiff = std::max( aP.x < m_Pos.x ? m_Pos.x - aP.x : m_Pos.x - x2, 0 );
-        ecoord_type ydiff = std::max( aP.y < m_Pos.y ? m_Pos.y - aP.y : m_Pos.y - y2, 0 );
+        ecoord_type xdiff = std::max(aP.x < m_Pos.x ? m_Pos.x - aP.x : m_Pos.x - x2, (ecoord_type)0);
+        ecoord_type ydiff = std::max(aP.y < m_Pos.y ? m_Pos.y - aP.y : m_Pos.y - y2, (ecoord_type)0);
         return xdiff * xdiff + ydiff * ydiff;    
 	}