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OpenWebGIS is online Geographic Information System

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OpenWebGIS is now in 3D!
openwebgis
Your maps may be now displayed on the surface of the earth as a globe. The developing has just begun.
Creating 3d maps in OpenWebGIS is done by means of integrating open source JavaScript libraries OpenLayers v. 2.11 and Cesium v.1.3.

OpenWebGIS_globeRotate

Cesium is an open source JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin. It uses WebGL for hardware-accelerated graphics, and is cross-platform, cross-browser, and tuned for dynamic-data visualization.
OpenLayers is an open source JavaScript library for displaying map data in web browsers. It provides an API for building rich web-based geographic applications similar to Google Maps and Bing Maps. The library was originally based on the Prototype JavaScript Framework.
In order to open the 3d map you must click on the button 3d_offin the upper right corner of the map. This button has the title "Add 3d Map. Globe ".  There will be a pop-up window in which you can set the desired size of the 3d map area in pixels.
OpenWebGIS_3dGlobe1
After installing the area size of 3d map and clicking Ok, your map will appear on the 3D globe of the Earth.
OpenWebGIS_3dGlobe2
For working with 3D map use these navigation instructions:
Pan view: Left click + drag;
Zoom view: Right click + drag, or Mouse wheel scroll;
Rotate view: Middle click + drag, or CTRL + Left click + drag.
At the moment, the main principles of working with 3D Globe in OpenWebGIS are following:

  • 1. What you see on 2d map, you can see on 3d on the map when starting 3d map. But you can choose other base layers.

  • 2. All changes and data editing, you can do only on 2d map. To see your changes on 3d map - click on the Update button over the globe.

  • 3. You can set the automatic data update on the 3d map – to do it, check the checkbox "refresh" and set the refresh time in milliseconds.

At the moment, the following issues are known when displaying data on 3d map:

  • 1. On the globe of the Earth  WMS and Image layers are not displayed if the data for these layers is taken from the servers which do not support CORS technology.

  • 2. WMS layers are always displayed under the vector layers.

Since the integration work of 3d map in OpenWebGIS has just begun, these issues will be resolved soon.
OpenWebGIS_3dGlobe3
As for 3d map creating the special technology of WebGL is used, then your hardware or browser may display an error message if they do not support this technology. Get information about it here http://cesiumjs.org/FAQ.html.
Or have a look at this extract taken from here http://gplat-web-dev-1.sydney.edu.au/:
"I am using Safari on Mac.
The WebGL is disabled by default in Safari. Follow the instructions below to enable WebGL. The WebGL support in Safari is experimental. The 3D interactive visualization may or may not work well. Open the Safari menu and select Preferences.
• Click the Advanced tab in the Preferences window.
• Check the Show Develop menu in menu bar checkbox at the bottom of the window.
• Open the Develop menu in the menu bar and select Enable WebGL.
I am using mobile phone / tablet.
The 3D interactive visualization may or may not work on a mobile device. It could work in Chrome on Android and Windows 8 devices. But it also depends on the model of your mobile device.
My computer is very old.
The grahpic card of your computer must support WebGL to make The 3D interactive visualization work. Almost all video cards from NVIDIA and AMD since 2004 support WebGL. Recent Intel video cards also work well. If the 3D interactive visualization does not work in Chrome on your desktop computer, you maybe consider using another computer instead."