[Requests] Comments on OpenGIS® City Geography Markup Language (CityGML) Encoding Standard (08-007r2)

[Cliff Behrens]

CityGML SWG members,

Please excuse my ignorance as I imagine these issues have been discussed 
before.  I am new to this OGC group and so don't have the benefit of 
prior discussions related to these issues.  It wasn't clear to me what 
requirements are referenced in PART B of the template below.

Cliff Behrens

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Part A to be completed once.  Iterate Part B as needed.


PART A


1. Evaluator:

Clifford Behrens, PhD
Senior Scientist & Director
Information Analysis
Applied Research
Telcordia Technologies, Inc.
Phone:  732-699-2619
FAX:    732-336-7015
Email:  cliff at research.telcordia.com

2. Submission: OpenGIS® City Geography Markup Language (CityGML) 
Encoding Standard (08-007r2)


PART B


1. Requirement: [General, #]


2. Implementation Specification Section number: 10.3, 10.11


3. Criticality: Major


4. Comments/justifications for changes:

I just completed a review of the editor's draft of CityGML 1.1.   
Obviously a lot of work went into it, and it is a very impressive 
document.  My interests in CityGML are primarily focused on responses to 
indoor emergencies, e.g., E911 calls.  With this in mind as I read 
through the draft, it wasn't clear to me how CityGML might support the 
following:

1)  How would one extract a simple 2D floorplan from a CityGML model?  
Would this involve the creation of a City object group, or would one 
retrieve all of the floor surfaces for rooms on a building storey?  It 
almost seems that there should be another LOD between LOD3 and LOD4.

2)  To provide a responder's current location and routing information 
through a building, it may be necessary to provide a reference point for 
a well-known building feature that (a) links a world coordinate system 
with a local coordinate system, and (b) can be used to compute the 
relative xyz position (or offset) of a person or object within the 
building.  How does the current CityGML encoding standard address this 
requirement?

-- 
Clifford Behrens, PhD
Senior Scientist&  Director
Information Analysis
Applied Research
Telcordia Technologies, Inc.
Phone:  732-699-2619
FAX:    732-336-7015
Email:  cliff at research.telcordia.com