WebGL Virtual Globe and Map Engine

<img src=“https://badge.fury.io/rb/cesium.png” alt=“Gem Version” />

In Gemfile file add line:

gem "cesium"

Run the bundle command to install it.

This gem relies on ‘requirejs-rails’ gem.

Make sure you follow the instruction from:

https://github.com/jwhitley/requirejs-rails

and you understand the concept of RequireJS:

http://requirejs.org

Now you are ready to use this gem :-)

For the convenience there is prepared route that will show you the globe. All you need to do is to modify your route.rb and add:

get 'cesium', to: 'cesium#index'

Now you can see the WebGL globe by visiting:

http://localhost:3000/cesium

Usage of this gem inside your own Rails application.

1. I presume you have a canvas tag in your view with id “globe”:

   <div class="fullSize">
     <canvas id="globe" class="fullSize"></canvas>
   </div>

2. You should have some CSS to define canvas size.

Here is an example that shows how to display the globe and cover 100% width & height of the wrapper

html, body {
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
}

.fullSize {
    width: 100%;
    height: 100%;
}

1. In the javascript module that is related to the view

Here I use application.js (coffee):

require [
  'jquery'
  'Cesium'
], ($, Cesium) ->

  $ ->

    canvas = $('#globe')[0]  # change this to match your needs!!!

    @scene = new Cesium.Scene canvas

    primitives = @scene.getPrimitives()

    bing = new Cesium.BingMapsImageryProvider(
      url: 'http://dev.virtualearth.net'
      mapStyle: Cesium.BingMapsStyle.AERIAL
      proxy: if Cesium.FeatureDetection.supportsCrossOriginImagery() then undefined else new Cesium.DefaultProxy('/proxy/')
    )

    terrainProvider = new Cesium.CesiumTerrainProvider(
      url: 'http://cesium.agi.com/smallterrain'
    )

    ellipsoid = Cesium.Ellipsoid.WGS84
    centralBody = new Cesium.CentralBody(ellipsoid)
    centralBody.getImageryLayers().addImageryProvider(bing)
    centralBody.terrainProvider = terrainProvider
    primitives.setCentralBody(centralBody)

    new Cesium.SceneTransitioner(@scene, ellipsoid)

    ##################################################################
    #   INSERT CODE HERE to create graphics primitives in the scene.
    ##################################################################

    animate = =>
      # INSERT CODE HERE to update primitives based on changes to animation time, camera parameters, etc.

    tick = =>
      @scene.initializeFrame()
      animate()
      @scene.render()
      Cesium.requestAnimationFrame(tick)

    tick()

    canvas.oncontextmenu = =>
      false

    onResize = =>
      width = canvas.clientWidth
      height = canvas.clientHeight
      return if canvas.width == width and canvas.height == height
      canvas.width = width
      canvas.height = height
      @scene.getCamera().frustum.aspectRatio = width / height

    $(window).on('resize', onResize)
    onResize()

We follow git-flow branching model which means:

• “master” branch should be more less stable

• “develop” branch is the place to integrate features & bug fixes

More about git-flow: github.com/nvie/gitflow

1. Fork it

2. Clone it

3. *Check out “develop” branch*

4. Create locally feature/fix branch

5. Write code & test it

6. Merge it back into local “develop” branch *as one commit*

7. Test it!

8. Send “pull request” against “develop” branch on github

1. Please check that the issue you are about to report is not already reported

2. Report it on GitHub Issues:

   https://github.com/bogwro/cesium/issues
   

• Bogumil Wrona (github.com/bogwro)

Clone specific version of the Cesium (-b VERSION_NUM):

git clone git@github.com:AnalyticalGraphicsInc/cesium.git -b 1.3 cd cesium ./Tools/apache-ant-/bin/ant clean ./Tools/apache-ant-/bin/ant combine ./Tools/apache-ant-/bin/ant buildApps ./Tools/apache-ant-/bin/ant runServer

After executing all of the build steps:

1. copy all files from Source folder

2. copy all files from Build/CesiumUnminified/Workers but not: „cesiumWorkerBootstrapper.js” and overwrite existing ones

• cesiumWorkerBootstrapper.js should be copied from Source folder

1. check which worker files are NEW and add them to the lib/ENGINE_NAME/engine.rb

• Rails’ Engine & all code which is part of this gem AND not part of the Cesium WebGL Globe:

  MIT License.

• All of the code that is part of Cesium WebGL:

  Apache License, Version 2.0

Please check the Cesium website for details:

http://cesium.agi.com
https://raw.github.com/AnalyticalGraphicsInc/cesium/master/LICENSE.md