Infolod and landmark: Spatial presentation of attribute information and computing representative objects for spatial data

In this paper, we will propose a way of visualizing attribute information f or spatial objects in the three-dimensional space and a calculation method for extracting a representative object from objects in a given region. In c onventional three-dimensional visualizations such as architectural simulati ons, most of the attention has been paid to image data such as colors, shap es, and textures of spatial objects. In this research, we will focus on the attribute information of spatial objects including image data. We propose InfoLOD concept which introduces the notion of level of detail (LOD) to att ribute information as well as image data such as photographs and computer g raphics for controlling the visualization of attribute information in a thr ee-dimensional space. The visualization is controlled based on distance and orientation, and we will also discuss the differentiation factor which vis ualizes the differences among the objects. In addition to visualization con trol, we will propose the LandMark algorithm for extracting a representativ e object from the objects in a given region based on their spatial occupanc y ratio and the uniqueness of the attribute data. The region for browsing m ay be specified manually by the user or may be automatically specified by s ome algorithm. Here, we discuss the spatial glue operation which dynamicall y retrieves regions containing objects with user-specified attribute inform ation unlike conventional method based on static mesh which are often used in GIS(Geographic Information System). We will also introduce some of our i mplementations in order to illustrate our ideas.