diff --git a/binding/miniffi-binding.cpp b/binding/miniffi-binding.cpp
index c543318f..084b9d96 100644
--- a/binding/miniffi-binding.cpp
+++ b/binding/miniffi-binding.cpp
@@ -44,6 +44,7 @@ MiniFFI_GetFunctionHandle(void *lib, const char *func)
     CAPTURE(GetWindowThreadProcessId);
     CAPTURE(FindWindowEx);
     CAPTURE(GetForegroundWindow);
+    CAPTURE(GetClientRect);
     CAPTURE(GetCursorPos);
     CAPTURE(ScreenToClient);
     CAPTURE(SetWindowPos);
diff --git a/src/fake-api.cpp b/src/fake-api.cpp
index 86e9b426..8976cf4e 100644
--- a/src/fake-api.cpp
+++ b/src/fake-api.cpp
@@ -6,6 +6,7 @@
 
 #include "sharedstate.h"
 #include "fake-api.h"
+#include "debugwriter.h"
 
 
 // Essentials, without edits, needs Win32API. Two problems with that:
@@ -65,6 +66,16 @@ MKXP_GetForegroundWindow(void)
     return 0;
 }
 
+BOOL __stdcall
+MKXP_GetClientRect(HWND hWnd, LPRECT lpRect)
+{
+    SDL_GetWindowSize(shState->sdlWindow(),
+                      (int*)&lpRect->right,
+                      (int*)&lpRect->bottom);
+    return true;
+}
+
+
 
 // FIXME: Mouse stuff doesn't work right now,
 // but at least it's not causing any Ruby exceptions
@@ -82,7 +93,6 @@ MKXP_ScreenToClient(HWND hWnd, LPPOINT lpPoint)
     return true;
 }
 
-
 BOOL __stdcall
 MKXP_SetWindowPos(HWND hWnd,
                   HWND hWndInsertAfter,
diff --git a/src/fake-api.h b/src/fake-api.h
index de334f6f..92d155d2 100644
--- a/src/fake-api.h
+++ b/src/fake-api.h
@@ -45,6 +45,9 @@ MKXP_FindWindowEx(HWND hWnd,
 DWORD __stdcall
 MKXP_GetForegroundWindow(void);
 
+BOOL __stdcall
+MKXP_GetClientRect(HWND hWnd, LPRECT lpRect);
+
 BOOL __stdcall
 MKXP_GetCursorPos(LPPOINT lpPoint);