| Abstrakt: |
The release of the Google Maps API has contributed significantly to the ubiquity of web maps. Nowadays, the most widely utilized tile pyramid technology has promoted more and more mashup visualization and web interaction. However, the multi-temporal, multi-source, and multi-scale characteristics of varied-level tile map data lead to inconsistencies between mashup cross-layer data (Goodchild and Li, 2012). The main reasons exist in: (1) the rapid change of landscapes and the different production periods from map sectors; (2) the diversified data-intensive web maps and various geographic standards from mapping agencies; and (3) the complexity of the dimensional and morphological changes in the geospatial data at different scales. The inconsistent visualization of these cross-layer tile maps may not only result in cognitive confusion to understand geospatial features but also lead to matching conflicts during the integration of web maps. In the case of river rendering over cross-layer tile maps, for example, some inappropriate rendering services visualize rivers that should be orderly distributed at different levels, in a misaligned way. Narrow rivers may be fractured at low levels of representation, or even exist as intertwined and overlapped rivers at higher levels. [ABSTRACT FROM AUTHOR] |
