diff --git a/effects/demo_wavywindows.cpp b/effects/demo_wavywindows.cpp
index 774af8f3f3..54de587120 100644
--- a/effects/demo_wavywindows.cpp
+++ b/effects/demo_wavywindows.cpp
@@ -66,8 +66,8 @@ void WavyWindowsEffect::paintWindow( EffectWindow* w, int mask, QRegion region,
                  ++j )
                 {
                 WindowVertex& v = data.quads[ i ][ j ];
-                v.move( v.x() + sin(mTimeElapsed + v.textureY() / 60 + 0.5f) * 10,
-                    v.y() + sin(mTimeElapsed + v.textureX() / 80) * 10 );
+                v.move( v.x() + sin(mTimeElapsed + v.originalY() / 60 + 0.5f) * 10,
+                    v.y() + sin(mTimeElapsed + v.originalX() / 80) * 10 );
             }
         }
 
diff --git a/lib/kwineffects.cpp b/lib/kwineffects.cpp
index 29d0bb6eea..494892abdf 100644
--- a/lib/kwineffects.cpp
+++ b/lib/kwineffects.cpp
@@ -452,8 +452,8 @@ void WindowQuadList::makeArrays( float** vertices, float** texcoords ) const
             {
             *vpos++ = at( i )[ j ].x();
             *vpos++ = at( i )[ j ].y();
-            *tpos++ = at( i )[ j ].textureX();
-            *tpos++ = at( i )[ j ].textureY();
+            *tpos++ = at( i )[ j ].tx;
+            *tpos++ = at( i )[ j ].ty;
             }
     }
 
diff --git a/lib/kwineffects.h b/lib/kwineffects.h
index 85b0b7dcd4..d10440c0da 100644
--- a/lib/kwineffects.h
+++ b/lib/kwineffects.h
@@ -368,13 +368,15 @@ class KWIN_EXPORT WindowVertex
         void move( float x, float y );
         void setX( float x );
         void setY( float y );
-        float textureX() const;
-        float textureY() const;
+        float originalX() const;
+        float originalY() const;
         WindowVertex();
         WindowVertex( float x, float y, float tx, float ty );
     private:
         friend class WindowQuad;
+        friend class WindowQuadList;
         float px, py; // position
+        float ox, oy; // origional position
         float tx, ty; // texture coords
     };
 
@@ -507,7 +509,7 @@ WindowVertex::WindowVertex()
 
 inline
 WindowVertex::WindowVertex( float _x, float _y, float _tx, float _ty )
-    : px( _x ), py( _y ), tx( _tx ), ty( _ty )
+    : px( _x ), py( _y ), ox( _x ), oy( _y ), tx( _tx ), ty( _ty )
     {
     }
 
@@ -523,6 +525,18 @@ float WindowVertex::y() const
     return py;
     }
 
+inline
+float WindowVertex::originalX() const
+    {
+    return ox;
+    }
+
+inline
+float WindowVertex::originalY() const
+    {
+    return oy;
+    }
+
 inline
 void WindowVertex::move( float x, float y )
     {
@@ -542,18 +556,6 @@ void WindowVertex::setY( float y )
     py = y;
     }
 
-inline
-float WindowVertex::textureX() const
-    {
-    return tx;
-    }
-
-inline
-float WindowVertex::textureY() const
-    {
-    return ty;
-    }
-
 /***************************************************************
  WindowQuad
 ***************************************************************/
@@ -590,8 +592,6 @@ void WindowQuad::checkUntransformed() const
     {
     assert( verts[ 0 ].py == verts[ 1 ].py && verts[ 2 ].py == verts[ 3 ].py
         && verts[ 0 ].px == verts[ 3 ].px && verts[ 1 ].px == verts[ 2 ].px );
-    assert( verts[ 0 ].ty == verts[ 1 ].ty && verts[ 2 ].ty == verts[ 3 ].ty
-        && verts[ 0 ].tx == verts[ 3 ].tx && verts[ 1 ].tx == verts[ 2 ].tx );
     }
 
 inline