diff --git a/dlls/d3dx9_36/d3dx9_36.spec b/dlls/d3dx9_36/d3dx9_36.spec
index 64ebd58fa3a..2534acfab05 100644
--- a/dlls/d3dx9_36/d3dx9_36.spec
+++ b/dlls/d3dx9_36/d3dx9_36.spec
@@ -16,7 +16,7 @@
 @ stub D3DXCompileShaderFromFileW
 @ stub D3DXCompileShaderFromResourceA
 @ stub D3DXCompileShaderFromResourceW
-@ stub D3DXComputeBoundingBox
+@ stdcall D3DXComputeBoundingBox(ptr long long ptr ptr)
 @ stub D3DXComputeBoundingSphere
 @ stub D3DXComputeIMTFromPerTexelSignal
 @ stub D3DXComputeIMTFromPerVertexSignal
diff --git a/dlls/d3dx9_36/mesh.c b/dlls/d3dx9_36/mesh.c
index c8637d89f87..08d6e2f7d47 100644
--- a/dlls/d3dx9_36/mesh.c
+++ b/dlls/d3dx9_36/mesh.c
@@ -24,6 +24,36 @@
 #include "d3dx9.h"
 
 
+/*************************************************************************
+ * D3DXComputeBoundingBox
+ */
+HRESULT WINAPI D3DXComputeBoundingBox(CONST D3DXVECTOR3 *pfirstposition, DWORD numvertices, DWORD dwstride, D3DXVECTOR3 *pmin, D3DXVECTOR3 *pmax)
+{
+    D3DXVECTOR3 vec;
+    unsigned int i;
+
+    if( !pfirstposition || !pmin || !pmax ) return D3DERR_INVALIDCALL;
+
+    *pmin = *pfirstposition;
+    *pmax = *pmin;
+
+    for(i=0; i<numvertices; i++)
+    {
+        vec = *( (D3DXVECTOR3*)((char*)pfirstposition + dwstride * i) );
+
+        if ( vec.x < pmin->x ) pmin->x = vec.x;
+        if ( vec.x > pmax->x ) pmax->x = vec.x;
+
+        if ( vec.y < pmin->y ) pmin->y = vec.y;
+        if ( vec.y > pmax->y ) pmax->y = vec.y;
+
+        if ( vec.z < pmin->z ) pmin->z = vec.z;
+        if ( vec.z > pmax->z ) pmax->z = vec.z;
+    }
+
+    return D3D_OK;
+}
+
 /*************************************************************************
  * D3DXIntersectTri
  */
diff --git a/include/d3dx9.h b/include/d3dx9.h
index b551eba4f2c..6b3bdf6c19d 100644
--- a/include/d3dx9.h
+++ b/include/d3dx9.h
@@ -24,6 +24,7 @@
 #include "d3d9.h"
 #include "d3dx9math.h"
 #include "d3dx9core.h"
+#include "d3dx9mesh.h"
 #include "d3dx9shader.h"
 #include "d3dx9tex.h"
 
diff --git a/include/d3dx9mesh.h b/include/d3dx9mesh.h
index c337ad249c5..5cfc25ee0e3 100644
--- a/include/d3dx9mesh.h
+++ b/include/d3dx9mesh.h
@@ -29,6 +29,7 @@ HRESULT WINAPI D3DXCreateBuffer(DWORD, LPD3DXBUFFER*);
 UINT    WINAPI D3DXGetFVFVertexSize(DWORD);
 BOOL    WINAPI D3DXBoxBoundProbe(CONST D3DXVECTOR3 *, CONST D3DXVECTOR3 *, CONST D3DXVECTOR3 *, CONST D3DXVECTOR3 *);
 BOOL    WINAPI D3DXSphereBoundProbe(CONST D3DXVECTOR3 *,FLOAT,CONST D3DXVECTOR3 *,CONST D3DXVECTOR3 *);
+HRESULT WINAPI D3DXComputeBoundingBox(CONST D3DXVECTOR3 *, DWORD, DWORD, D3DXVECTOR3 *, D3DXVECTOR3 *);
 BOOL    WINAPI D3DXIntersectTri(CONST D3DXVECTOR3 *, CONST D3DXVECTOR3 *, CONST D3DXVECTOR3 *, CONST D3DXVECTOR3 *, CONST D3DXVECTOR3*, FLOAT *, FLOAT *, FLOAT *);
 
 #ifdef __cplusplus