Few questions about VBI.

[Former Member]

Hi

We are using VBI in a traffic analysis system.

Here are some questions I meet.

     1.     How to get current zoom level?

     For now, I write as below

          var canvas = e.getParameters().canvas;

          var m_Scene = canvas .m_Scene;

          var zoomLevel = m_Scene.GetCurrentZoomlevel();

I think it is not a legal way, and is there any better way to get it?

     2.     How to get the position(longitude and latitude) of the map center?

               Is there any method to get them?

     3.     I use Route VO to draw roads on the map. There are almost 3,000 VOs on the map at the same time. It makes a lot of cost on handling mouseover events. Can I shut down it so it can perform better?

     4.     And, is it suitable for me to use in a traffic analysis system?

That's all.

Look forward to your reply

[ralf_rath · Accepted solution]

sorry for the late reply! It is vacation time at the moment.

1+2. you can retrieve changes in the zoom level and the centerpoint with an event:

See here the details:

3. as I understood you dynamically build your map and use VOs to display the vector information.

The application should keep the number of objetcs low. I don't know if interactions are needed but using an underlying road map and display only the interactive objects.

4. it depends a little bit on your use case, I don't have the details. You wrote that you have some performance problems with the mouseover events - processing time consuming methods in mouseover events is critical because the user may moves the mouse quickly. We have done some equivalent use cases showing traffic aggregation over time. But as I said here we need more details.

I hope that helps .

[Former Member · Accepted solution]

Thank you, thank you very much.

It is quite helpful.