Implementation of the map split component (I)-component for converting map numbers and longitude and latitude

There are two ways to split the current graph: latitude and longitude split and rectangular split. The domestic drawing standards adopt latitude and longitude split. For details, refer to the national standard "national basic scale Topographic Map split and No. GB/T 13989-92".

The main feature of the latitude and longitude split is that the row and longitude numbers are subdivided Based on the millions of parts and the row and column methods to obtain the row and column numbers at different scales, get the score number based on the millions of shards and the row and column numbers. The positions between 0.5 million and are 10-bit encoded. The first three digits are the number of millions of images, the fourth digit is the current scale, and the last six digits are the row and column. Less than three digits of the row and column numbers are filled with three digits, which are aligned before the row and column numbers. For details, refer to the national standard.

The main consideration here is how to write components for application in the project. For plotting, the split is used to facilitate output and printing. As a matter of fact, the range is used more in China, especially in surveying and mapping, with more large-scale applications.

Generally, the split has two requirements in the GIS system. One is to obtain the image range through the split number. For example, we need to automatically output a series of images in a region, then, you need to obtain the output range based on the Image number before the output can be made. Second, in a typical GIS system, it is often necessary to determine the image frame and its range based on the current coordinate point. How can we implement the demand?

Because it is commonly used, you can consider writing it as a component. According to the national standard, the 0.5 million-split is based on one million split. Therefore, you can achieve one million split before other split. For example. I have designed a million-frame splitting interface, in which I can query the row and column numbers of millions of images by longitude and latitude, the query range of millions of image numbers, and the coordinate check map number.

 

Next, on the basis of millions, I continue to design similar methods, such

I500kto5ksheetline is an interface I wrote to process other scales. The methods in the interface reuse the millions of split methods.

The above interfaces basically meet the requirements for split. The following is a test case.

Reprinted Please note: http://blog.csdn.net/jx1228/archive/2011/04/08/6308863.aspx