To estimate the quality of a media operation, various metrics for the different media types are available. Although there are metrics that value the visual quality of operations on 3D data as well as on 2D data, there is no metric for the mapping of 2D data on 3D data, such as the mapping of texture images on 3D mesh models. In order to provide a metric that weighs the quality of textured 3D objects with respect on the human visual perception after the 2D and 3D data is watermarked independently, this work combines a mapping operation, a 2D metric and a 3D metric. The resulting approach allows measuring the visual impact of modifications of the texture as well as the 3D model on the final 3D object with all its textures mapped. Common application scenarios for that metric are video games, where 2D textures watermarked independent form the 3D model, but during the game play the textured 3D model is displayed.