Polygon graphics document default values updated

[abu271]

Hey @OmarShehata I updated the documentation, let me know if more changes need to be made.

[cesium-concierge]

Thanks for the pull request @abuDarda97!

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• Works in 2D/CV.
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[OmarShehata]

Thanks @abuDarda97 ! To help me out, can you post the lines of code that show where the default is being created to that value so I can easily verify?

Also, did you do a "find all" across all the files of code in the Source/ folder to see if there are any other heightReference values that are similarly missing a doc in other files?

[abu271]

@OmarShehata The default heightReference value is defined here https://github.com/AnalyticalGraphicsInc/cesium/blob/master/Source/DataSources/PolygonGraphics.js#L156

For extrudedHeightReference it is stated here https://github.com/AnalyticalGraphicsInc/cesium/blob/master/Source/DataSources/PolygonGraphics.js#L173

I just carried out a find all search query for heightReference under the Source folder. I found a few files where the default value for heightReference is missing. I would update these files ASAP.

[hpinkos]

Thanks or the PR @abuDarda97! This looks fine to me.