Sub-string hotspot draft text

[Lofton Henderson <lofton@rockynet.com>]

All --

The attached draft substring hotspot text needs your careful reading.

Normally I wouldn't include an issue-discussion section with a drafting 
assignment. However we have not talked about some minor details yet, so 
here is some background explanation of what I have done in the 
(preliminary) drafting...

The only substantive change for WebCGM 2.1 will be to restrict what APS 
types are allowed in Text Open State (TOS): grobject, para, and subpara, 
and their content when they occur in TOS. I think all of the rest falls out 
of the clarifying CGM:1999 corrigendum -- e.g., the permissibility of APS 
markup in text open state, and the restriction that such an APS can contain 
only Append Text and not any nested APS markup, etc.

However, the feature is obscure, and the rules are buried in the arcane 
EBNF and State Table of CGM:1999 (corrected). Therefore, some brief 
explanation will also be added to Ch.3.

I thought of adding some informative description to Ch.2 as well, however 
substring hotspotting seems too detailed for that chapter. I finally 
decided that "less is better" for such an arcane feature, and limit it to a 
precise treatment in section 3.2.1, Application Structures.

As far as I can tell -- I looked at every chapter -- nothing else in the 
document is actually incorrect or inaccurate by skipping mention/treatment 
of substring APS.

A pointer to the corrigendum will be included in 1.2 "Normative references".

Have I missed anything?

Is everything correct?

Regards,
-Lofton.

Title: Substring hotspot drafting

Sub-string hotspot draft text for WebCGM 2.1

discussion

Normally I wouldn't include this discussion section with a drafting assignment. However we have not talked about some issues yet, so here is what I have done in the (preliminary) drafting...

The only substantive change for WebCGM 2.1 will be to restrict what APS types are allowed in Text Open State (TOS): grobject, para, and subpara, and their content when they occur in TOS. All of the rest falls out of the clarifying CGM:1999 corrigendum -- e.g., the permissibility of APS markup in text open state, and the restriction that such an APS can contain only Append Text and not any nested APS markup, etc.

However, the feature is obscure, and the rules are buried in the arcane EBNF and State Table of CGM:1999 (corrected). Therefore, some brief expository references will also be added to Ch.3. I thought of adding some informative description to Ch.2 as well, however substring hotspotting seems too detailed for that chapter. I finally decided that "less is better" for such an arcane feature, and limit it to a precise treatment in 3.2.1, Application Structures.

As far as I can tell, nothing else in the document is actually incorrect by skipping mention/treatment of substring APS.

A pointer to the corrigendum will be included in 1.2 "Normative references".

drafting changes

new normative reference

Section 1.2: Add this new normative reference after the ISO/IEC 8632:1999(E) item:

ISO/IEC 8632-1:1999/Cor 2:2007

This corrigendum to CGM:1999 clarifies the permissibility and usage rules of Application Structures in the Text Open State of CGM:1999. Available at: http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=50315

clarify content of 'grobject' APS

Section 3.2.1.1: Replace

"The content of an APS of type 'grobject' is (see fragment syntax for definition of EBNF notation):"

with

"Except when occurring in Text Open State (see 3.2.1.7), the content of an APS of type 'grobject' is (see fragment syntax for definition of EBNF notation):"

clarify content of 'para' APS

Section 3.2.1.3: Replace

"'Para' APSs may contain any CGM graphical content allowed by this profile."

with

"Except when occurring in Text Open State, 'para' APSs may contain any CGM graphical content allowed by this profile.

Section 3.2.1.3: Replace

"The content of an APS of type 'para' is (see fragment syntax for definition of EBNF notation):"

with

"Except when occurring in Text Open State (see 3.2.1.7), the content of an APS of type 'para' is (see fragment syntax for definition of EBNF notation):"

clarify content of 'subpara' APS

Section 3.2.1.4: Replace

"'Subpara' APSs may contain any CGM graphical content allowed by this profile, but may not contain nested APS."

with

"Except when occurring in Text Open State (see 3.2.1.7), 'subpara' APSs may contain any CGM graphical content allowed by this profile. 'Subpara' APS may not contain any nested APS."

Section 3.2.1.4: Replace

"The content of an APS of type 'subpara' is (see fragment syntax for definition of EBNF notation):"

with

"Except when occurring in Text Open State (see 3.2.1.7), the content of an APS of type 'subpara' is (see fragment syntax for definition of EBNF notation):"

add new subsection detailing substring APS

3.2.2.7 APS in Text Open State

The rules of CGM:1999 (corrected) allow an APS to occur in Text Open State, i.e., after a 'notfinal' RESTRICTED TEXT (RT) element but before the terminating 'final' APPEND TEXT (AT) element. This allows, for example, a substring comprising one of the interior APPEND TEXT elements in a RT-AT-AT-...-AT sequence to be contained within an APS. Thus, for example, the APPEND TEXT element (substring) could be the target of a link, or could be the source of a link (a "hotspot").

Such an APS is referred to as a substring APS.

WebCGM 2.1 restricts the APS types of such substring APS to: 'grobject', 'para', and 'subpara'. For APS of these types that are not substring APS, the content rules are as quoted in sections 3.2.1.1, 3.2.1.3, and 3.2.1.4 respectively. If an APS of one of these types is a substring APS, then its content is restricted as follows by the rules of CGM:1999 (corrected): only the APPEND TEXT element and those text attributes normally allowable in Text Open State (under CGM:1999 rules).

The allowable APS Attributes for 'grobject', 'para', and 'subpara' are as designated in 3.2.1.1, 3.2.1.3, and 3.2.1.4 respectively, regardless of whether or not they are substring APS.