Transparent background not working

```
I have downloaded the latest jsc3d version from
http://jsc3d.googlecode.com/svn/trunk/jsc3d/jsc3d.js.

Now for turn off the background i am using bellow code

viewer.setParameter('Background', 'off');

But its not working.Can You help me,thank you.
```

Original issue reported on code.google.com by `prasen.b...@gmail.com` on 19 Aug 2014 at 10:32

Start by inspecting jsc3d.js and the viewer.setParameter('Background', 'off') call to determine how background settings are handled. Reproduce the reported behavior with the downloaded version and verify that the viewer renders without the background when the setting is applied.

Written by the indexing model from the issue text.