Probabilistic Surfaces: Point Based Primitives to Show Surface Uncertainty

Gevorg Grigoryan                                   Penny Rheingans             
University of Maryland Baltimore County            University of Maryland Baltimore County  


Abstract                                                          
Eficient and informative visualization of surfaces with uncertainties 
is an important topic with many applications in science and    
engineering. Examples include environmental pollution border line       
identification, identification of the limits of anoil basin, or discrimination
between contaminated and healthy tissue in medicine. This       
paper presents an approach for such visualization using points as      
display primitives. Our approach is to render each polygon as a collection
of points and to displace each point from the surface in the     
direction of the surface normal by an amount proportional to some       
random number multiplied by the uncertainty level at that point.      
This approach can be used in combination with other techniques      
such as pseudo-coloring and shading to give rise to eficient and    
revealing visualizations. The method is used to visualize real and  
simulated tumor formations with uncertainty of tumor boundaries.        



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