Here are the different types of shape that are supported by blur modifiers.
      These shapes are configurable in the 
                    
                      Parameters
                     editor:
      
                    
                      
                      
                      
                      
                        
                          |   Gaussian Blur set as "Normal" Blending mode with varying luminosity threshold 
 |   Gaussian Blur set as "Screen" Blending mode with varying luminosity threshold 
 |   Gaussian in "Normal" Blending mode and cycle through all aggregator types 
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                          |   Box Blur 
 |   Circle Blur 
 |   Ring Blur 
 | 
                        
                          |   Hexagonal Blue 
 |   Hexagonal Blur in "Screen" mode with "Maximum" aggregator type and varying luminosity threshold 
 |   Zoom Blur 
 | 
                        
                          |   Spin Blur 
 |   Directional Blur 
 |   4 Star Blur 
 | 
                        
                          |   8 Star Blur 
 |   Random Box Blur 
 |   Random Circle Blur 
 | 
                        
                          |   Random Triangle Blur 
 |   Random Triangle with "Smoothing" parameter variation 
 |   Diffuse Blur 
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                          |   Custom : Multi-Pass algorithm with 2 directional blur (one still and one rotating) 
 |   Custom : Combine algorithm with 2 directional blur (one still and one rotating) 
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