[x3d-public] JSweet translation of X3DJSAIL to JavaScript: need specific design goals first

[Don Brutzman]

John, certainly we need to pay attention to "how" a library conversion is performed.  JSweet is promising, and we have a number of conversion approached demonstrated already.

But that is distracting and confusing way to solve a problem and leads to "fire, ready, aim!" implementation pathologies.

A further risk might be that JSweet might carry through unnecessary Java programming idioms, but presumably they have sorted through that well already.

First things first, please.  Let's begin with defining design goals.  That's how we accomplished creating Java and Python programming-language bindings for X3D.

What we really need to understand is "what" a sharable X3D JavaScript library looks like, and how JavaScript programmers might then use it to author interactive X3D models.

Authoring use-case environments are
1. Script inside X3D scene graph,
2. Script in outer HTML5 web page,
3. Standalone programmatic use in node.js

Now get specific.  Recommend listing pseudocode and design patterns for JavaScript Transform class and JavaScript X3D types, comparing:

a. X3D ECMAScript specification,
b. X3D Script code fields (class variables) and methods,
c. good general-practice OO design pattern(s) in common use,
d. current X3D JSON approach, is it OK or improvable further?
e. compare/contrast Transform approach with X3DJSONLD,
f. compare/contrast Transform approach with X_ITE,
g. compare/contrast Transform approach with X3DOM,
h. compare/contrast Transform approach with three.js,
j. compare/contrast Transform approach with any other javascript libraries of interest,
i. compatibility of Transform approach with Angular, React, jquery, other common JavaScript frameworks for HTML.

We did this kind of comparison for X3D JSON design and it helped make a confusing understandable, eventually leading to good design decisions.

If interested parties prepare this kind of comparison, and understand "what" we want that has general appeal, then progress refinement will be straightforward.

Many people use JavaScript these days, especially with node.js - check whether they like the result.

When you have solid patterns then we convert 4,000 X3D example scenes (from .x3d -> .js) to match, providing unit tests.  Lather, rinse, repeat...

Hope this outline helps.  Good luck out there!  8)

all the best, Don
-- 
Don Brutzman  Naval Postgraduate School, Code USW/Br       brutzman at nps.edu
Watkins 270,  MOVES Institute, Monterey CA 93943-5000 USA   +1.831.656.2149
X3D graphics, virtual worlds, navy robotics http://faculty.nps.edu/brutzman