Computer Graphics Tokyo, now in its fourth year, has established a world-wide reputation as an international technical conference, presenting work of high quality in the field of computer graphics. Each conference has been attended by a couple of thousand partiCipants from all over the world and tens of thousands have visited the exhibition. After strict peer review, 34 papers were accepted this year, of which about 40% were from the USA, 30% from Japan, 20% from Europe, and 10% from Canada. A good balance of papers on advanced research results, industrial/marketing surveys, and computer art technology has made Computer Graphics Tokyo an indispensable forum for researchers, engineers, and administrators working in this field. Computer graphics is a rapidly developing and expanding area and it is not easy to keep abreast of all the progress that has been made. This volume contains the proceedings of Computer Graphics Tokyo '86 and provides the reader with a comprehensive survey of the state of the art in computer graphics. Computational geometry (Chapter 1) is one of the fastest growing areas in computer graphics. This is well recognized as the basis of shape modeling. After shapes are modeled, they are displayed for visual observation. Chapter 2 on rendering presents various novel methods and technological innovations for visualizing shapes. To make display systems more acces­ sible to users, rich visual interfaces and languages are being designed, as shown in Chapter 3. Visual data bases for sharing graphics-and image-data are handled in Chapter 4.