Get point at length, tangent angle and segment 
            
            
                
            
            Point at length
            
            
            Accuracy
            
            Tangent
            
            Segment at length
            
                
            
            
            Quality
            
                
            
            Path data conversions
            
                
                
            
            
            Orange point= point calculated from pathpata; black point= calculated from getPointAtlength. Both point
                should be as congruent as possible.
            Input you pathdata