Small fixes: typo, spacing and using ::ScreenToClient() instead of ::GetWindowRect()

modules/highgui/include/opencv2/highgui.hpp

@@ -76,9 +76,9 @@ enum { EVENT_MOUSEMOVE      = 0,
        EVENT_MBUTTONUP      = 6,
        EVENT_LBUTTONDBLCLK  = 7,
        EVENT_RBUTTONDBLCLK  = 8,
-       EVENT_MBUTTONDBLCLK  =9,
+       EVENT_MBUTTONDBLCLK  = 9,
-       EVENT_MOUSEWHEEL     =10,
+       EVENT_MOUSEWHEEL     = 10,
-       EVENT_MOUSEHWHEEL    =11
+       EVENT_MOUSEHWHEEL    = 11
      };
 
 enum { EVENT_FLAG_LBUTTON   = 1,

modules/highgui/src/window_w32.cpp

@@ -40,7 +40,7 @@
 //M*/
 
 #include "precomp.hpp"
-#include <windowsx.h> // required for GET_X_LPARAM() and GET_Y_LPARAM() marco
+#include <windowsx.h> // required for GET_X_LPARAM() and GET_Y_LPARAM() macros
 
 #if defined WIN32 || defined _WIN32
 
@@ -1395,13 +1395,9 @@ MainWindowProc( HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam )
           flags |= (delta << 16);
 
           POINT pt;
-          {
+          pt.x = GET_X_LPARAM( lParam );
-             // since The coordinates are relative to screen so get screen size.
+          pt.y = GET_Y_LPARAM( lParam );
-             RECT windowRect;
+          ::ScreenToClient(hwnd, &pt); // Convert screen coordinates to client coordinates.
-             ::GetWindowRect( window->hwnd, &windowRect );
-             pt.x = GET_X_LPARAM( lParam ) - windowRect.left;
-             pt.y = GET_Y_LPARAM( lParam ) - windowRect.top;
-          }
 
           RECT rect;
           GetClientRect( window->hwnd, &rect );