Visual attention is a key feature to optimize visual experience of many multimedia applications. 2D visual attention computational modeling is an active research area considering the visualization of natural images on a conventional display. In this paper, we question the ability of such models to be applicable to single computer-generated objects rendered at different sizes (on a conventional display). We benchmark state of art visual attention models and investigate the influence of the viewpoint on those computational models applied on volumetric data and this to get a better understanding of how viewpoint information could be integrated into view-based approaches. To do so, a subjective experiment was conducted and a fine analysis was led using the variance analysis statistical method.