Since last 90s, our country began to research and develop the digital image map cartography technology, which is applied in mapping, land, agriculture, ocean, etc more or less.

The Ricci map gained the nickname the "Impossible Black Tulip of Cartography" because it was so hard to find.

Map projection in cartography is a way to present a two-dimensional curved surface on a plane, such as a normal map. Figure 2 shows a Traverse Mercator projection.