IRC log of sdw on 2021-01-07

Timestamps are in UTC.

13:57:12 [RRSAgent]
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13:57:12 [RRSAgent]
logging to
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]
14:06:32 [ted]
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]
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]
14:13:32 [ted]
-> 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]
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]
-> 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]
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]
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]
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]
14:33:57 [ted]
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]
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]
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]
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]
14:48:47 [ted]
Jeremy: any other topics for today?
14:49:07 [ted]
Linda: Responsible Use Note
14:50:35 [RobSmith]
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]
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]
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]
14:57:26 [ted]
Linda: anyone else have new years regrets or resolutions?
14:57:45 [RobSmith]
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 ted
14:59:20 [cperey]
When is next meeting?
14:59:27 [ChrisLittle]
14:59:34 [cperey]
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]
Zakim has left #sdw
14:59:41 [RRSAgent]
I see no action items