This set of examples will use the first scene. It is real simple (in terms of elements), but it is sufficient to illustrate the projection issues. For the purposes of this discussion assume that the display screen is sufficiently large to show everything that is desired to be displayed. Also assume that the rendering software does not enlarge the displayed scene to fit the screen.
For the last nine months I have been working on a declarative language for VR/AR/MR to display 3D content in a browser. I have called the language XSeen.
The importance of examples in learning a new language cannot be overstated. This section contains illustrative examples of using XSeen. As has been discussed there are a number of similarities between XSeen and A-Frame and X3D. These will be obvious in the examples. It is possible to intermix tags from each language in a manner that makes sense.
The X3D language uses mixed case node and field names. In some cases field values are specified as case-specific names. This is standard XML. HTML allows for any case and converts tags and attribute names to lower case before use. The HTML language does not impose specific case requirements on attribute values. XHTML is XML-based, so it is case sensitive; however, all tag and attribute names are defined as lowercase.