[x3d-public] Feature comparison of glTF and X3D as Interchange Formats

[Michalis Kamburelis]

2017-09-22 18:26 GMT+02:00 Leonard Daly <Leonard.Daly at realism.com>:
> Michalis,
>
> I think I now understand your concerns. I did not want to imply that the
> comparison included all X3D capabilities. I tried to make that clear though
> additional text prior to the table and footnotes, but perhaps not clear
> enough. Do you have any suggestions for making it clearer that the
> comparison does not include all X3D capabilities?
>

I have two suggestions:

1. Use another icon (not the "X") to mark "Features supported by at
least two X3D browsers, but not present in the X3D Interchange
profile" in the X3D column. I think that this would really help: when
you see an icon (not a simple "Yes" or "No" mark) then you read a
tooltip to know what it means, and maybe you also read a footnote to
know the details.

    This strategy worked on me when I saw the "Feature available with
conditions" mark you already used in other cells. I read the tooltip,
and the footnotes, to know what it means, and I understand that
sometimes there isn't a simple "yes" or "no" answer.

    It's up to you whether to make it "at least two X3D browsers", or
"at least three ...", or "at least two commonly used X3D browsers" or
such, of course. I think that the following rows could deserve this
icon in their "X3D" column:

    - Quad surface model (in spec: [Indexed]QuadSet in CAD comopnent)

    - Advanced apperance (not in spec, but cross-browser extension:
CommonSurfaceShader)

    - Mesh skin (in spec: H-Anim component (unfortunate name for a
component useful for general skinned animation, not just humanoids,
but that's a different discussion))

    - Custom Shaders (in spec: Programmable shaders component)

    - Joint animation (in spec: H-Anim component)

2. Clarify that an "Interchange profile" is a subset of X3D, and
commonly browsers implement much more. After the sentence:

    """
    As this comparison is just for model formats, only the V3.3
Interchange Profile of X3D is considered.
    """

    add this:

    """
    Note that the "Interchange profile" support is in practice a
"minimum" feature set expected from a reasonable X3D browser. Most X3D
browsers implement much more than only the "Interchange profile"
portion of the X3D standard.
    """

Also, unrelated to above suggestions: There is a Unity -> X3D export
script: https://github.com/thefranke/unityx3d . So this one possibly
should just be changed to "Yes" :)

Best regards,
Michalis