IRC log of sdw on 2021-01-07

Timestamps are in UTC.

13:57:12 [RRSAgent]

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logging to https://www.w3.org/2021/01/07-sdw-irc

13:57:15 [Zakim]

RRSAgent, make logs Public

13:57:17 [Zakim]

please title this meeting ("meeting: ..."), ted

13:58:22 [brinkwoman]

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14:01:12 [ClemensPortele]

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14:01:21 [jtandy]

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14:01:31 [ClemensPortele]

present+ ClemensPortele

14:01:38 [ted]

Chair: Linda

14:01:39 [ted]

Present+ Ted

14:01:49 [jtandy]

hi folks - just updating my webex :-|

14:01:51 [ted]

scribenick: ted

14:02:32 [jvanulden]

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14:02:57 [ted]

Present+ Linda, Peter, Joost, RobS, Clara

14:03:18 [jtandy]

Present+ jtandy

14:03:59 [ted]

Chair+ Jeremy

14:05:01 [RobSmith]

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14:05:04 [brinkwoman]

regrets+ Scott, Bill

14:05:34 [cboyd]

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14:06:09 [ted]

Agenda: https://lists.w3.org/Archives/Public/public-sdwig/2021Jan/0014.html

14:06:32 [ted]

cccccceukvetfedndegtbeifghbfrrujetujnbjcllkt

14:06:41 [ted]

Topic: MapML

14:07:16 [ted]

Peter: it is important for MapML to have coordinate and tile matrix sets together

14:08:17 [ted]

… EGSP data set is separate from the notion of scale. whenever GIS data is used, scale is vital for visual representation on map

14:08:35 [ted]

… it would be convenient if the coordinate system recommendation had concept of scaling

14:08:54 [ted]

Present+ Chris

14:09:16 [ted]

s/cccccceukvetfedndegtbeifghbfrrujetujnbjcllkt//

14:09:45 [ted]

… having scales or resolutions recommended would be helpful for consumption

14:10:11 [ted]

… web feature service without notion of scale you get highest resolution possible which may not be appropriate for certain uses

14:10:52 [ted]

Chris: I raised that with OGC API for tiles. they have been focused on styles etc

14:11:15 [ClemensPortele]

Chris, this is not a tiles issue, its a maps issue

14:11:22 [ted]

… I am trying to get them to revisit

14:11:48 [ted]

… it is desireable to request tiles at a given scale that is device capability compatible

14:12:06 [ted]

… in short, I agree with you

14:13:02 [ted]

Peter: as I mentioned in my email, the standardized definition probably dates back to GIS era when you typically already had local to desktop/workstation the different scaled resources

14:13:13 [jtandy]

q?

14:13:32 [ted]

-> https://lists.w3.org/Archives/Public/public-sdwig/2021Jan/0002.html Peter's email

14:13:50 [ted]

Jeremy: corner reference system is needed as well as scale as you called it

14:14:05 [ClemensPortele]

q+

14:14:08 [ted]

… I think it was in Clemens' email that we should not bind these too closely together

14:14:27 [ted]

… you cite the WFS work and want these concepts combined

14:14:47 [ted]

-> https://lists.w3.org/Archives/Public/public-sdwig/2021Jan/0008.html Clemens' email

14:15:04 [ChrisLittle]

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14:15:11 [ted]

Clemens: I think the CRS come from survey era which predates GIS

14:15:30 [ChrisLittle]

present ChrisLittle

14:15:35 [ted]

… these are reference systems and don't need a scale but provide eg limited accuracy

14:15:51 [ted]

… CRS don't really have a scale component to them

14:16:16 [ted]

… at some scale or zoom level, certain features or information should be suppressed

14:16:38 [jtandy]

q?

14:16:44 [cperey]

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14:16:50 [ted]

… for tiling, each is at a certain zoom level and hierarchy is defined with accompanying OGC standards

14:17:10 [jtandy]

q+ to ask PR to describe what he can't do with today's APIs

14:17:15 [ted]

… scale or zoom level is supported in many APIs

14:17:38 [ted]

… we have a call for review on work items. we are focusing on geometry simplification

14:18:05 [ted]

… welcome proposals for handling feature/scale relationship

14:18:33 [ted]

… this can also be addressed in Best Practices revision

14:18:49 [ted]

Peter: some WFS do support scale/zoom as a parameter

14:18:50 [ChrisLittle]

q+

14:19:03 [ted]

… some features are either too small or big

14:19:47 [ted]

… how you model your data need to take into consideration having feature disappear at a certain scale for instance

14:20:13 [ted]

… data modeler needs to know the recommended scales. we can use inheritance model

14:20:18 [Zakim]

jtandy, you wanted to ask PR to describe what he can't do with today's APIs

14:21:02 [ted]

Jeremy: if I'm using a coordinate reference system, what you're saying is there should be a set of zoom scales that are recommended for use with that particular CRS

14:21:15 [ted]

Peter: correct

14:22:19 [ted]

Jeremy: for a given municipality, the data is limited and others at eg a county zoom level

14:22:39 [ted]

… is the choice of CRS coupled to choice of zoom scale or zoom scale to application you are trying to support?

14:22:44 [ted]

Peter: good question

14:23:27 [ted]

… agree there could be scale recommendations from town level in British National Grid

14:24:09 [cboyd]

You did a better job than I could Jeremy

14:24:18 [ted]

Present+ Christine

14:24:36 [ted]

Jeremy: you are positing there are a number of data providers and with scaling we can overlay them reasonably well

14:25:02 [ted]

Peter: I'm unaware of ETRS89 but guess you would have to reproject data for combining

14:25:33 [ted]

Jeremy: a consistent set of zoom levels would be preferable across different data providers then?

14:25:36 [ted]

Peter: yes

14:25:37 [ted]

q?

14:26:05 [ted]

Jeremy: if I have a list of zoom levels somewhere, would that help?

14:26:25 [ted]

… encouraging people to publish data at specific zoom levels?

14:26:50 [ted]

Clemens: I think we are the wrong group of people to raise that. we should discuss with CRS

14:27:03 [ted]

… they have a concept of scope

14:27:46 [ted]

… there are regionally appropriate systems, eg the British National Grid isn't as useful in Germany

14:28:47 [ted]

… I don't think it is a CRS issue. if anything gets added to its definition, it should come from CRS group

14:28:54 [ted]

Peter: fair enough

14:29:20 [ted]

Jeremy: as a data publisher, you have control over the server and should have additional meta data available

14:29:51 [ted]

Clemens: you can unlimited zoom detail but then reasonably depending on data you may restrict information to specific zoom level

14:30:10 [ted]

… this is a conscious decision already being used

14:30:35 [ted]

Jeremy: zoom level already expressed in that case?

14:31:20 [ted]

Clemens: Google's tiling scheme that is widely used

14:31:38 [ted]

… OGC doesn't call it zoom level but tile metrics which isn't immediately intuitive

14:32:25 [ted]

Jeremy: agree. anyone wanting to publish with web marcater (sp? google's tile scheme) can include level

14:32:48 [ted]

Clemens: the zoom level from their tiling scheme differs from others with their own conventions

14:33:03 [ted]

… how do we express zoom level?

14:33:28 [brinkwoman]

s/marcater/mercator/

14:33:57 [ted]

https://developers.google.com/maps/documentation/javascript/coordinates

14:34:23 [ted]

Jeremy: how do we combine data from different schemes and data providers?

14:35:01 [ted]

… a list of scales coupled to CRS is one way, another by an algorithm from Web Features standard

14:35:14 [jtandy]

q?

14:35:34 [ted]

Clemens: the scale range you want to support when you publish your feature data is not dependent on CRS

14:35:45 [ted]

Jeremy: we are not trying to line up pixelated tiles

14:35:49 [jtandy]

ack ChrisLittle

14:35:58 [ted]

Chris: I want to respond to an earlier comment of Clemens'

14:36:09 [ted]

… what sort of device am I using and what do I want to see on it

14:36:32 [ted]

… cluttering/decluttering is a decision of the client application and zoom level mucks that up

14:37:05 [ted]

… Clemens wants to simplify geometry from a set of features. that is separate from a filtering aspect

14:37:54 [jtandy]

(I guess the ultimate geometry simplification is down to a point ... and then client applications could determine how to deal with situations where many point features are too close together?)

14:38:16 [ted]

Clemens: from features API perspective, if feature shown as a certain zoom level is part of it

14:38:55 [ted]

… at some zoom level or scale you would simply show a point. you would not return certain features at a given scale level

14:39:27 [ted]

… adjacent polygons with attributes can be returned as you zoom out

14:39:56 [ted]

… filtering features and getting them ready is server side, combining is post processing

14:40:23 [ted]

Jeremy: at simplest scale a geometry can be a single point and it is still related to a set of features

14:40:47 [ted]

Clemens: correct but dependent on zoom level, point could be an airport but when you zoom in have more detail

14:41:49 [ted]

… if you zoom out to a certain level you would want to only present certain, larger airports and suppress others

14:42:11 [ted]

… this filtering requires extra knowledge and there is a question if we should even do this

14:42:19 [ted]

q?

14:42:34 [ted]

Linda: I am trying to relate to SDWBP

14:42:56 [ted]

… it is only partially related and the rest about visualization and user interaction

14:43:11 [ted]

Clemens: it is related to the convenience API

14:43:35 [ted]

… you need to think about how people want to interact with your data. we already have text along these lines we might want to expand

14:44:08 [ted]

… how to make data more usable. you may want to return different data if it is to be used for mapping for instance

14:44:45 [ted]

Peter: would it be convenient to have recommended scale sets attached to CRS for those who want to make a feature service

14:45:09 [ted]

… you know you are going to have to generated tiled features

14:45:20 [ted]

… this is why I am suggesting/asking for advice

14:45:31 [ted]

… sounds like we should discuss with CRS group

14:45:53 [ted]

Clemens: not sure it is the right thing. scale depends on the data not on the CRS

14:46:10 [ted]

… still could be worth discussing with that group to get their opinion

14:46:31 [ted]

Jeremy: how you want to present data is often closely related to type of application[s] you want to support

14:46:32 [ChrisLittle]

+1 to clemens - data linked not CRS

14:46:42 [RobSmith]

+1

14:46:44 [ted]

… do we want to engage the CRS folks?

14:46:59 [ted]

… Peter you want us to put you in touch with them?

14:47:10 [ted]

Peter: sure and can bring back here response

14:47:48 [ted]

[Clemens provides suggestion on specific OGC group and individual to contact]

14:48:28 [ted]

Peter: I have corresponded with Roger before, comfortable talking with him directly and will report back

14:48:31 [jtandy]

q?

14:48:47 [ted]

Jeremy: any other topics for today?

14:49:07 [ted]

Linda: Responsible Use Note

14:50:35 [RobSmith]

q+

14:50:45 [ted]

… believe we are ready to publish

14:50:47 [jtandy]

ack RobSmith

14:50:55 [ted]

Ted: @@Ed, timing

14:51:29 [brinkwoman]

q+ to ask if there's progress to report on the BP

14:51:59 [ted]

RobS: we want to get feedback on this Note, not meant to be a finished work yet which is what prompted wanting to get it published soon

14:52:05 [Zakim]

brinkwoman, you wanted to ask if there's progress to report on the BP

14:52:20 [ted]

Linda: wonder if we have updates on BP work?

14:52:52 [ted]

Clara: we are still working through it and was delayed in lead up to holiday break

14:53:04 [ted]

… still seeking input and welcome contributions

14:53:32 [ted]

Linda: I can try to find someone at Geonovum

14:53:48 [ted]

… Christine, you want to follow up on WoT?

14:54:12 [ted]

Christine: indeed, want to focus discussion on discovery and scheduling with Michael McCool

14:54:31 [jtandy]

q+ to ask @cperey for the meeting date

14:54:58 [RobSmith]

q+

14:55:01 [ted]

… will let people know timing if interested. want to combine with Augmented Reality, how do you discover sensors and data available from an AR client including someday a browser

14:55:14 [jtandy]

q-

14:56:11 [ted]

Jeremy: if you have date/time for AR and WoT that would be handy

14:56:51 [ted]

Christine: 19 January at 11EDT

14:57:08 [ted]

… anyone interested, let me know and I can add you

14:57:09 [jtandy]

WoT meeting: Tue 19th Jan, 11AM Eastern

14:57:12 [PeterR]

q+

14:57:26 [ted]

Linda: anyone else have new years regrets or resolutions?

14:57:45 [RobSmith]

https://w3c.github.io/sdw/proposals/geotagging/webvmt/#virtualguide

14:57:53 [ted]

RobS: I sketched out a WoT use case related to WebVMT

14:58:07 [brinkwoman]

ack next

14:58:22 [ted]

Christine: I appreciate that Rob. we are not limiting the discussion to AR

14:58:31 [ted]

RobS: understood and appreciated

14:58:47 [brinkwoman]

ack PeterR

14:59:02 [ted]

Peter: forgot to ask if ok to make an issue in SDW repo?

14:59:08 [cperey]

Thank you!

14:59:17 [ted]

Linda: yes and please link to the email discussion [and minutes]

14:59:18 [RRSAgent]

I have made the request to generate https://www.w3.org/2021/01/07-sdw-minutes.html ted

14:59:20 [cperey]

When is next meeting?

14:59:27 [ChrisLittle]

bye

14:59:34 [cperey]

Bye!

14:59:40 [Zakim]

leaving. As of this point the attendees have been ClemensPortele, Ted, Linda, Peter, Joost, RobS, Clara, jtandy, Chris, Christine

14:59:40 [Zakim]

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14:59:41 [RRSAgent]

I see no action items