RE: [cgmo-webcgm] ISSUE 9d11: Should lineEdgeTypeDef be generalized or focused?

["Cruikshank, David W" <david.w.cruikshank@boeing.com>]

I'm in favor of generality and I think our use cases support this:

 

From the requirements document (http://www.oasis-open.org/committees/download.php/26392/WebCGM%202_1%20Requirements.htm)

In another usage, LINE AND EDGE TYPE DEFINITION (and similarly hatch style) default setting could allow a specific exact dash style to be assigned to the generic CGM line types 1,2,3,4,5.

 

I don't think that use case limits us from doing anything.

 

From the attributes table (http://www.oasis-open.org/committees/download.php/26099/Attributes_Table.pdf)

The ability to be able to define the sizes of the dash, dots, spaces, line spacing (for hatches) for the line types that are pre-defined. This is useful to make lines look consistent across viewers and hard-copy versions.

While the second sentence doesn't capture the whole use case, the first sentence implies that control over the sizes of dashes, dots, and gaps is required.

Perhaps we need to revise the use case to include alignment of the visual appearence of V1 and V2 files when used in conjunction with V3 files in an application.

Do we need to update the use cases in the requirements and/or the attributes table?

Dave

Technical Fellow - Graphics/Digital Data Interchange
Boeing Commercial Airplane
206.544.3560, fax 206.662.3734
david.w.cruikshank@boeing.com

 

---

From: Lofton Henderson [mailto:lofton@rockynet.com]
Sent: Monday, May 05, 2008 10:51 AM
To: CGM Open WebCGM TC
Subject: [cgmo-webcgm] ISSUE 9d11: Should lineEdgeTypeDef be generalized or focused?

From my review of Ch.9 defaults stuff, 
http://lists.oasis-open.org/archives/cgmo-webcgm/200805/msg00005.html 
,
one particularly substantive issue stands out:

ISSUE 9d11: Should 
the lineEdgeTypeDef ACI item be generalized or 
restrictive?

Discussion:  The lineEdgeTypeDef element in the current 
(CD) Ch.9 ACI actually allows all of the generality of the corresponding 
CGM:1999 element. For example, it could allow the redefinition of LineType 3 
(dash-dot) to look like 'dash' (LineType 2).  The use case is somewhat 
lacking in detail, but *seems* to indicate that the purpose is to give uniform 
appearance to the generic predefined line types, 1..5.  Do we want to allow 
the generality to change the appearance from the generic description?  Or 
do we want to try to parameterize so that this could not be done? E.g., 
lengthOfDash, interDashGap, interDotGap, etc. 

Recommendation: 
none.  More discussion is needed from users and vendors to refine the 
desired capabilities in the use cases.  In favor of generality? Or in favor 
of restrictiveness?

Note:  Presumably ISSUE 9d12 -- same issue about 
hatchStyleDef -- will have the same resolution.  (Although it is 
conceivable that the use cases *could* lead to different 
resolutions.)

[1] http://docs.oasis-open.org/webcgm/v2.1/cd01/WebCGM21-Config.html