Using a square aspect ratio for the map, the maximum latitude shown is approximately 85.05 degrees. Since the Mercator projection goes to infinity at the poles, it doesn’t actually show the entire world. It’s a cylindrical projection, which means that north and south are always straight up and down, and west and east are always straight left and right. Square buildings should appear square, not rectangular. This is especially important when showing aerial imagery, because we want to avoid distorting the shape of buildings. It’s a conformal projection, which means that it preserves the shape of relatively small objects. We chose to use the Mercator projection, which looks like this:Īlthough the Mercator projection significantly distorts scale and area (particularly near the poles), it has two important properties that outweigh the scale distortion: To make the map seamless, and to ensure that aerial images from different sources line up properly, we have to use a single projection for the entire world. This document describes the projection, coordinate systems, and addressing scheme of the map tiles, which collectively are called the Bing Maps Tile System. To make this interaction as fast and responsive as possible, we chose to pre-render the map at many different levels of detail, and to cut each map into tiles for quick retrieval and display.
Bing Maps provides a world map that users can directly manipulate to pan and zoom.
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