[x3d-public] Online conversion tool from anything (like glTF) -> X3D updated

[Michalis Kamburelis]

My conversion tool on https://castle-engine.io/convert.php was just
updated to include all the latest improvements done in Castle Game
Engine (with respect to X3Dv4, glTF and more).

In particular, you can now use it to convert glTF 2.0 files to X3D (in
classic or XML encoding) and the output will automatically use X3Dv4
PhysicalMaterial nodes to express glTF PBR materials.

In general our approach to convert glTF -> X3D is documented on
https://github.com/michaliskambi/x3d-tests/wiki/Converting-glTF-to-X3D
. So if you're unsure how/why given glTF construction is translated to
X3D, this page probably has an answer :)

You can open the resulting files in view3dscene (
https://castle-engine.io/view3dscene.php ).

Reminder: you can also use view3dscene to do the same conversion
(interactively or in batch mode). Use "File -> Save As X3D..." menu
item, or command-line as documented on
https://castle-engine.io/view3dscene.php#section_converting . We
provide the online tool just as a convenience for people who don't
want to install view3dscene.

Regards,
Michalis