From Grid Control to GIS software

The story begins in 1993 a long time ago. This year, Uncle Gates's Microsoft released Visual Basic 3.0 and VB 3.0 added the latest support for odbc2.0 and the support for the jet Data Engine, use the Grid Control and Data Control to create outstanding data window applications Program Since then, VB has become the most popular language in the world.

The topic is more distant. In 1970 of June, Edgar Frank codd, a senior researcher at the IBM St. Joseph research laboratory) the article "relational model of large shared database data" was published on communications of ACM. It is doomed that data in the Information Age is stored in two-dimensional data tables one by one, in this era, these relational databases will all run around, just like the heart.

To display the relational data, a grid control must be available. The grid control becomes the standard for all rad development tools. Such as VB, such as Delphi, and numerous third-party controls.

The above is gossip. To display data in the grid, the simplest way is to useCodeDraw the grid. For example, in VB, many people use textbox or label controls to simulate the grid (heaven knows who taught them to do that ), or use GDI to draw a grid in the painting method of VC. These are the practices of Prehistoric humans, although there are still many people doing this.

Finally, the programmer said that to use a grid, there were countless grid controls. All controls are satisfied. The data source or a database connection, such as ADO recordset; or the grid exposure interface, the program fills in as needed; or the original method is used for a 2-for loop, fill one cell with one cell. The first method is simple. The second method is flexible without sacrificing efficiency. The program can obtain the required data and fill the grid as needed. If a grid control says that to use me, you must convert the data to my private format, then it will be ugly and become a discussion after dinner, even if the control is highly efficient.

Back to the GIS world, if someone says that the display efficiency of MapX is relatively high and the effect is relatively good, can we use the underlying analysis function of ArcGIS to display maps through MapX.

Yes?

No?

The answer is, This is not impossible. However, to use a prehistoric human practice, we need to traverse ArcGIS data N times and dynamically add it to MapX through code, similar to the third method of using the Grid Control mentioned above, the grid control usually displays hundreds of data records.

Space technology-related fields have always been a special world. In this world, it is difficult for people to communicate with each other, and some people have been busy with each other. For example, a map is congested. It's like you have a relative in the United States. To tell you how to use ArcGIS, you must fly to the United States and then fly back after listening to him. No phone, no letter, no QQ or MSN.

Finally, in the great ArcGIS 9.2, the data interoperability function is enhanced. This function allows ArcGIS to directly read (or write) hundreds of other data formats without the need to convert the format, finally, a huge step forward towards the open world.

The so-called no love for no reason, no hate for no reason, the GIS will not be such an idiot or asshole for no reason. So what has caused the current situation? The only answer is probably only the particularity of spatial data. GIS is not the only thing that can express spatial data. CAD is an ancient concept and is better than GIS. With such a predecessor, GIS focuses more on massive data management and spatial analysis. In turn, the advantages of CAD in drawing and drawing lead to a lot of GIS data being made by CAD, then convert to GIS format.

In the CAD field, I don't know when to start, Autodesk is a big family, and the AutoCAD format has become something similar to industry standards (is the AutoCAD format open ?). It is the same as the current MS Office standard in the office market.

GIS in earlier years was an academic research tool or a special tool in a special department, similar to MATLAB or SPSS, GIS is used by experts. As a result, write a program to convert the binary file to another file format. Such a master, then simply do gdal, OGR. However, with the development of the industry, the demand for spatial information has also increased. GIS is more used to build so-called information systems than as tools like office or AutoCAD. However, without other information technology fields, GIS chose another principle: an integrated solution for underlying databases, intermediate analysis engines, and upper-layer display.

If one is an independent company, this road may still be accessible. previously mentioned ArcGIS reader will become an industry standard, but no one in this market can become the dominant. There is a conflict between demand and supply. The focus of the conflict lies in data and interoperability.

As a result, people say that the industry needs standards and the OGC specification is in place.

There are well-executed regulations in this world, such as the traffic rules in Beijing, and how they are implemented, such as the traffic rules in Wuhan and the OGC rules. The specifications are put in that way. Many people look pity and have the ability to add these things to open-source GIS.

Now, we can see that postgis is getting better and better. We can see that mainstream database systems are starting to support their own spatial data. We can see JTs and tops with specialized spatial data operations and geoserver with data release, openlayers with data display, so we have reason to believe that grid controls in this industry will become increasingly useful.

For traditional GIS software providers, there may be two ways ahead, either to adapt to the trend of the times, or to develop professional software such as MATLAB and SAS, to serve the research of geographic information science.

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