diff --git a/effects/invert/invert.cpp b/effects/invert/invert.cpp
index c90ec4eba3..c8aa4828e0 100644
--- a/effects/invert/invert.cpp
+++ b/effects/invert/invert.cpp
@@ -106,8 +106,8 @@ void InvertEffect::paintWindow( EffectWindow* w, int mask, QRegion region, Windo
             texw = nearestPowerOfTwo(texw);
             texh = nearestPowerOfTwo(texh);
             }
-        m_shader->setUniform("textureWidth", (float)texw);
-        m_shader->setUniform("textureHeight", (float)texh);
+        m_shader->setTextureWidth( (float)texw );
+        m_shader->setTextureHeight( (float)texh );
 
         data.shader = m_shader;
         }
diff --git a/lib/kwinglutils.cpp b/lib/kwinglutils.cpp
index 97ed83fafe..8a52a4ba07 100644
--- a/lib/kwinglutils.cpp
+++ b/lib/kwinglutils.cpp
@@ -734,6 +734,8 @@ GLShader::GLShader(const QString& vertexfile, const QString& fragmentfile)
     mValid = false;
     mVariableLocations = 0;
     mProgram = 0;
+    mTextureWidth = -1.0f;
+    mTextureHeight = -1.0f;
 
     loadFromFiles(vertexfile, fragmentfile);
     }
@@ -950,6 +952,25 @@ bool GLShader::setAttribute(const QString& name, float value)
     return (location >= 0);
     }
 
+void GLShader::setTextureHeight(float height)
+    {
+    mTextureHeight = height;
+    }
+
+void GLShader::setTextureWidth(float width)
+    {
+    mTextureWidth = width;
+    }
+
+float GLShader::textureHeight()
+    {
+    return mTextureHeight;
+    }
+
+float GLShader::textureWidth()
+    {
+    return mTextureWidth;
+    }
 
 
 /***  GLRenderTarget  ***/
diff --git a/lib/kwinglutils.h b/lib/kwinglutils.h
index 82d09e904e..b4c70ac7f6 100644
--- a/lib/kwinglutils.h
+++ b/lib/kwinglutils.h
@@ -219,6 +219,10 @@ class KWIN_EXPORT GLShader
         int attributeLocation(const QString& name);
         bool setAttribute(const QString& name, float value);
 
+        void setTextureWidth( float width );
+        void setTextureHeight( float height );
+        float textureWidth();
+        float textureHeight();
 
         static void initStatic();
         static bool fragmentShaderSupported()  { return mFragmentShaderSupported; }
@@ -236,6 +240,8 @@ class KWIN_EXPORT GLShader
         QHash< QString, int >* mVariableLocations;
         static bool mFragmentShaderSupported;
         static bool mVertexShaderSupported;
+        float mTextureWidth;
+        float mTextureHeight;
     };
 
 /**
diff --git a/scene_opengl.cpp b/scene_opengl.cpp
index 6bd9c2b5b9..3240ff3f0f 100644
--- a/scene_opengl.cpp
+++ b/scene_opengl.cpp
@@ -1650,6 +1650,15 @@ void SceneOpenGL::Window::prepareShaderRenderStates( TextureType type, double op
     shader->setUniform("opacity", (float)opacity);
     shader->setUniform("saturation", (float)saturation);
     shader->setUniform("brightness", (float)brightness);
+
+    // setting texture width and heiht stored in shader
+    // only set if it is set by an effect that is not negative
+    float texw = shader->textureWidth();
+    if( texw >= 0.0f )
+        shader->setUniform("textureWidth", texw);
+    float texh = shader->textureHeight();
+    if( texh >= 0.0f )
+        shader->setUniform("textureHeight", texh);
     }
 
 void SceneOpenGL::Window::prepareRenderStates( TextureType type, double opacity, double brightness, double saturation )