<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;
color:windowtext;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
pre
{mso-style-priority:99;
mso-style-link:"HTML Preformatted Char";
margin:0in;
margin-bottom:.0001pt;
font-size:10.0pt;
font-family:"Courier New";
color:black;}
span.HTMLPreformattedChar
{mso-style-name:"HTML Preformatted Char";
mso-style-priority:99;
mso-style-link:"HTML Preformatted";
font-family:"Courier New";
color:black;}
.MsoChpDefault
{mso-style-type:export-only;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
/* List Definitions */
@list l0
{mso-list-id:632636882;
mso-list-template-ids:-1;}
@list l0:level1
{mso-level-tab-stop:.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level2
{mso-level-tab-stop:1.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level3
{mso-level-tab-stop:1.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level4
{mso-level-tab-stop:2.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level5
{mso-level-tab-stop:2.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level6
{mso-level-tab-stop:3.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level7
{mso-level-tab-stop:3.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level8
{mso-level-tab-stop:4.0in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level9
{mso-level-tab-stop:4.5in;
mso-level-number-position:left;
text-indent:-.25in;}
@list l1
{mso-list-id:1977876852;
mso-list-template-ids:-1;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style></head><body lang=EN-US link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal><b>From: </b><a href="mailto:Leonard.Daly@realism.com">Leonard Daly</a><br><br><o:p></o:p></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><div><ol start=1 type=1><li class=MsoNormal style='color:black;mso-margin-top-alt:auto;margin-bottom:12.0pt;mso-list:l1 level1 lfo1'>>DOM is not a file format, but an API. X3D (in JSON or XML) is a file format. How do you handle conversion of a file format to an API? Is the result something that populates the DOM tree? Is it something else? Note that XML -> DOM is a well-defined conversion (and built-in to web browsers) that populates the DOM tree with the data from the XML document. DOM contains data, structure, and methods that are not present in the XML document; but are part of the standard DOM and DOM-tree definition.<o:p></o:p></li></ol><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><span style='color:black'>I mean DOM tree in your parlance. DOM is commonly acceptable for DOM tree, for example, on W3schools.com. I do not read standards for the most part! I do agree that model is a poor term for non-architectural purposes when you mean interface. I will use hyperobject to refer to your DOM tree in the future. It’s not a document or a model!<o:p></o:p></span></p><ol start=2 type=1><li class=MsoNormal style='color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l1 level1 lfo1'>>DOM very explicitly does not allow multi-parents. I think I understand your statements that when converting from a multi-parent structure to one that only allows single parent, you create a copy of the original. This resolves the multi-parent issue into one that may break run-time. As I understand your description: if A & B are parents of node-subtrees and X is DEFed in the A tree and USEd in the B tree; then the A and B trees have distinct copies of X (called X and X'). Do you add mechanisms so that runtime changes to X also change X'?<o:p></o:p></li></ol><p><o:p> </o:p></p><p>>Unreal (and perhaps Unity) get around this issue (node reuse in a single-parent environment) by making X a class and having each USE of X to be a new instance of that class. Changes to the X class are propagated to all instances. Each instance may define instance-specific methods/data that override those from the inherited class. It is also possible to sub-class X' and add in instance-specific methods/data.</p></div><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>I do something similar in my programs, and leave it up to SAI to solve. SAI has setUSE, which should solve the issue. Does it?<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>Is that simple enough?<o:p></o:p></span></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:black'>John<o:p></o:p></span></p></div></body></html>