Popular WebGIS experience

• Microsoft Virtual Earth

Of course, Microsoft's Virtual Earth is the first place! Look at Los Angeles, 3D view, and can be rotated, up and down adjusted from the distance, supporting keyboard arrow keys, very suitable for fine-tuning. This 3D extension must be installed and supported only when the operating system is in English.

Let's see how Microsoft arranges its own home:

We can see that every building is clearly marked and marked in red.

• Google Map

I believe everyone has used Google Earth, which is better than sticking your wings on your shoulders! Anybody, everywhere, anytime! Compared with the magical fat client such as Google Earth, Google map is far from being able to achieve smooth visual enjoyment, without any angle of view. Of course, this is also a flaw in the current HTML, Ajax, and so on. Compared with Microsoft Virtual Earth, Google map is a pile of dishes. From this point of view, Microsoft's WebGIS is indeed one step ahead of Google!

• Eemap

I remember when I started playing eemap last year. At that time, I thought it was really a wiki and a new idea. No wonder many domestic "players" are also very keen on it. I just think that the map data of eemap is limited, and there is no result for searching Los Angeles. Her data is mainly from China, but not all major cities in China have satisfactory precision data. Look at the following: I tag a "Chongqing University" on it last year, and the accuracy is only here, the images of baodi, including Microsoft and Google, which are regarded as a gold mine by the central government in Chongqing, are vague and disappointing.

• Sougou

Sougou's service is also good. Although it is only 2D visual, it also looks real. After all, when you need something, you can search for it. Below is the "Holiday Inn Chongqing Changdu" I searched in sougou. I found the hotel on this map for a tour:

Indeed, the current "Electronic Map Heat" has been hot like an egg roasting on the fire. You can all ask about its fragrance. Now, the problems faced by various WebGIS service providers may not be due to these two:

Access speed problems caused by rich data sources and large data volumes

However, the access speed above is good, that is, image data in some regions (major cities) is still insufficient. A computer newspaper once reported that civil society organizations in the UK were measuring geographic data. A group of volunteers carried GPS measuring instruments to various places in the city to map geographic data, this is indeed a feasible and good method. After all, the above big companies' geographic data was bought from some satellite data providers by money.

Electronic Map brings convenience to all aspects of life, and also enables a group of curious online worms to find and dig on it.