tailieunhanh - Map-based Mobile Services Design,Interacton and Usability Phần 3

Ngược với các kỹ thuật tích hợp khác như tích hợp chức năng hoặc tích hợp dữ liệu, việc cài đặt từng chức năng riêng lẻ trong kinh doanh không bị thay đổi trong phương án tích hợp ứng dụng doanh nghiệp. | 4 An Incremental Strategy for the Fast Transmission of Multi-Resolution 63 faẹade elements. Three different kinds of structures can be identified for which appropriate reduction methods are defined extrusion or intrusion offset and corner see Fig. . Fig. . Elimination of short facade Sn offset a intrusion extrusion b and corner c based on Sester et al. 2004b These operators are interesting in a client-server context with limited resources by reducing the amount of transferred data. Generalised dataset can be sent before a more detailed one. Furthermore such operators guarantee the sharing of geometries which is essential in an incremental strategy. Consequences on incremental transitions between different levels of detail If we observe results of these operators on different representations of regions and polylines we can deduce the different changes to perform on an object in order to rebuild its more generalised or detailed representation. Case of simplified polylines In consequence of the simplification process eliminated points need to be inserted in the generalised representation of the polyline in a refinement transition and must be removed from the most detailed one during a generalisation transformation. In this last case a choice must be done between conservation of shared points or removal of details. Moreover vertices can be moved between different LoDs for example in order to respect the topological relations with neighboring objects coordinates of these points must be changed during a refinement or generalisation transition. Case of simplified regions In generalisation transition vertices can be either kept for the common points removed for the details or moved for preserving parallelism and rectangularity properties of building . In refinement transition vertices can be either moved or introduced for adding details . These generalisation operators are expected to be performed on the server side and followed by a process of increment creation. A