This volume presents the proceedings of COMPUTER GRAPHICS INTERNATIONAL '93 (COl '93), the Eleventh International Conference of the Computer Graphics Society (CGS), COl '93 has been held in Lausanne, Switzerland from June 21-25,1993 under the theme Communicating with Virtual Worlds.

I: User Interface and Virtual Reality.- Future Directions in Advanced User Interface Design aron Marcus.- Using the Whole Hand in the Human-Computer Interface.- Communicating with Virtual Worlds: Accessing Data, Information and Knowledge by Multimedia Technologies.- Distributed, Multi-Person, Physically-Based Interaction in Virtual Worlds.- User Guidance in Virtual Worlds.- Computer Aided Color Coding.- II: Rendering Techniques.- Solving the Radiosity Linear System.- Lighting Model on Gas and Liquid.- Display of Multi-isosurfaces by the Volume Rendering Technique from Data Sets in 3D Space.- Shadow Volume Generation from Free Form Surfaces.- Fast Analytic Rendering with Adaptive Tables.- A Generation Model for Human Skin Texture.- A Context Sensitive Texture Nib.- III: Geometric Modelling.- Geometric Reasoning for the Extraction of Surface Shape Properties.- Representation of Geophysical Maps with Uncertainty.- Reconstruction of an Object Shape from Multiple Incomplete Range Data Sets Using Convex Hulls.- A New Shape Control and Classification for Cubic Bézier Curves.- Local and Global Control of Cao En Surfaces.- Interactive Surface Design Using Recursive Subdivision.- A Display Algorithm of Brush Strokes Using Bézier Functions.- Interpolating Solid Orientations with Circular Blanding Quaternion Curves.- G2 Continuous Interpolation over Rational Curve Meshes.- Blending Polyhedra with NURBS.- Direct Manipulation Devices for the Design of Geometric Constraint Networks.- A Methodology for Geometric Algorithm Development.- A Fast Incremental Algorithm for Computing the Voronoi Diagram of a Planar Shape.- IV: Modelling and Animation.- Abstract and Natural Forms from Iterated Function Systems.- Verification of Visual Characteristics of Complex Functions fa,c(z) = z?+c.-Creating Virtual Fur and Hair Styles for Synthetic Actors.- Modeling Blades of Simple Leaves.- A Model of Hands and Arms Based on Manyfold Mappings.- The Elastic Surface Layer Model for Animated Character Construction.- The GATI Client/Server Animation Toolkit.- Combined Visualization of Contour Levels and 3D Volumes in Molecular Graphics.- Manufacturing Simulation for Turning Machine Centers.- V: Hardware and Parallel Processing.- PROOF II: A Scalable Architecture for Future Highperformance Graphics Systems.- Realtime Synthesis of Super-Realistic Moving Goldfish Using Small-Scale Parallel Transputers.- Parallel Volume Rendering Finite Element Data.- Parallel Processing in Radiosity Calculations.- A Massively Parallel Processing Approach to Fast Photo-Realistic Image Synthesis.- Real-Time Hardware for Image Edge-Thinning Using a New 11-Pixel Window.- Parallel Creation of Linear Octrees from Quadtree Slices.- A Graphical Hierarchical Flowchart Generator for Parallel Fortan Programs.- VI: Image Processing.- A Fast Algorithm for Digital Image Scaling.- A Method of Dynamic Image Montage and Simple Scene Model Construction for Landscape Simulation.- A Necessary Condition of Block Edge Detection and Hierarchical Representations of the Kernel Form of the Hexagonal Grid.- Partial Surface Identification Based on 3-D Multiple Spatial Filtering.- Analysis and Recognition of Medical Images: 1. Elastic Deformation Transformation.- Image Segmentation Using Colour Information and its Application in Colonscopy.- A Multi-Processor Vision System.- Conference Organization.- Author Index.- Keyword Index.