Mass-Spring Systems Versatile Visualization Techniques Flexible Surfaces to Multidimensional Scaling Brian Duffy MSIM 742: Visualization II
Brian Duffy MSIM 742: Visualization II 2 May 7, 2008 Mass-Spring Construction Masses Bound by Springs Surface Vertices Individual Objects Relative Resistance Values Springs Push & Pull Masses Use Hooke’s Law for Tension Spring Coefficients Drive Alignment Impose Chain Reactions Iterative Adjustments Drive Proper Placement of Masses
Brian Duffy MSIM 742: Visualization II 3 May 7, 2008 Diverse Uses Fabric Simulation Human Tissue Simulation Simulating Hair Multidimensional Scaling Large Datasets with Many Variables Natural Clustering of Similar Entities
Brian Duffy MSIM 742: Visualization II 4 May 7, 2008 Fabric Simulation Springs Between Vertices Rectangular for Basic Shape Diagonals Prevent Shearing Bend Springs Control Folding Collisions Cause Draping Vertex-level Collisions Springs Control Fabric Shape Forces Applied to Vertices Gravity, Wind, Mechanical
Brian Duffy MSIM 742: Visualization II 5 May 7, 2008 Human Tissue Simulation Critical Vertices Move Based on Muscles Skin Surface Follows Critical Vertices Skeletal Structure Imposes Limitations on Movements
Brian Duffy MSIM 742: Visualization II 6 May 7, 2008 Simulating Hair Wisp Skeletons Use Both Linear and Angular Springs Between Rigid Bodies Implicit Backward Euler Method Improves Speed and Supports Torsional Motion
Brian Duffy MSIM 742: Visualization II 7 May 7, 2008 Multidimensional Scaling Project N-Dimensions in 2D or 3D Views Calculate Proximity Between Points Springs Between Points Proximity is Relaxed Spring Length N 2 – N Springs Required Large Data Sets Present Challenges
Brian Duffy MSIM 742: Visualization II 8 May 7, 2008 Multidimensional Scaling Improved Processing Time Sample √N Points as Parents Position Parents Assign Each Point to a Parent via Nearest Neighbor Process Place Springs Within Clusters and Between Parent Nodes Reduced from N√N to N 5/4 Calculations 100,000+ Items with 14+ Dimensions are Now Possible
Brian Duffy MSIM 742: Visualization II 9 May 7, 2008 Future Work Cross-Culture Historical Time Cluster Replaces Traditional Timelines Focuses on Similarities of Events and Conditions Interactive Humans Convey Details of the Events Personalize Event Causes and Consequences Realistic Expressions and Gestures
Brian Duffy MSIM 742: Visualization II 10 May 7, 2008 Conclusions Mass-Spring Systems are Versatile Visualization Tools Relatively Simple Iterative Implementations Best Effects on Small to Medium Sized Datasets Powerful Tool for All Graphics Software Developers