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RE: [Minutes] 2015-08-05

From: <Simon.Cox@csiro.au>
Date: Wed, 5 Aug 2015 23:57:54 +0000
To: <public-sdw-wg@w3.org>
Message-ID: <2A7346E8D9F62D4CA8D78387173A054A602976C9@exmbx04-cdc.nexus.csiro.au>
Apologies - I dropped out part way through the SVG presentation. 
Its hard enough staying up until midnight (especially after a 6am start). 
A silent presentation just killed it for me - I actually fell asleep. 

Simon Cox | Research Scientist
CSIRO Land and Water
   37 Graham Road, Highett, Vic 3190
   PO Box 56, Highett, Vic 3190
Tel +61 3 9545 2365 | Mob +61 403 302 672
simon.cox@csiro.au | http://people.csiro.au/C/S/Simon-Cox

From: Phil Archer [phila@w3.org]
Sent: Thursday, 6 August 2015 12:06 AM
To: SDW WG Public List; Satoru Takagi
Subject: [Minutes] 2015-08-05

The minutes of today's meeting are at
http://www.w3.org/2015/08/05-sdw-minutes with a snapshot below.

Thanks very much to Satoru Takagi for joining to talk about SVG -
there's clearly a lot of interest and we'll need to follow up. As ever,
the issue of coordinate reference systems is the hard problem.

           Spatial Data on the Web Working Group Teleconference

05 Aug 2015

    See also: [2]IRC log

       [2] http://www.w3.org/2015/08/05-sdw-irc


           Kerry, stakagi, kostas, aharth, Linda, Payam, Kostas,
           ChrisLittle, phila, SImonCox, billroberts,
           Alejandro_Llaves, frans, BartvanLeeuwen, AndreaPerego

           Lars Svensson, Rachel Heaven, Ed Parsons


           andreas harth


      * [3]Topics
          1. [4]Welcome new members
          2. [5]Use Cases and Requirements: Editors' stocktake
          3. [6]SVG for spatial: Presented by Satoru Takagi
          4. [7]Best Practice Issues as raised by Jeremy
      * [8]Summary of Action Items

    <trackbot> Date: 05 August 2015

    <kerry> scribe: andreas harth

    <kerry> scribenick: aharth

    <kerry> [9]http://www.w3.org/2015/07/29-sdw-minutes.html

       [9] http://www.w3.org/2015/07/29-sdw-minutes.html

    <Payam> +1

    <phila> PROPOSED: Approve last week's minutes

    <Payam> +1

    <Linda> +1

    <kerry> +1

    <Alejandro_Llaves> +1

    <BartvanLeeuwen> +1

    <phila> RESOLVED: Approve last week's minutes

    <billroberts> +1

    <ChrisLittle> +1

    kerry: patent call

    <phila> [10]Patent Call

      [10] https://www.w3.org/2015/spatial/wiki/Patent_Call

    <phila> kerry: This is the patent call that satisfies OGC
    process. It's important that any patent claims are declared

    <phila> ... Please remember to type present+ and your name

    <phila> ... this records your presence in the minutes

Welcome new members

    <phila> kerry: Invites kostas to introduce himself

    kostas: university of surrey

    <phila> kostas: I'm a KTP associate... at Univesity of Surrey
    (works with Payam)

    kerry: welcome Satoru Takagi, editor of svg recommendation

    <phila> kerry: Also welcoms Satoro Takagi, editor an an SVG

    <stakagi> Hello!

Use Cases and Requirements: Editors' stocktake report

    kerry: update on document
    ... frans and alejandro are both here


      [11] http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html

    frans: url of current version of the document
    ... first public working draft has been published a while ago
    ... with feedback on the public comments lists
    ... some issues left, issues are labelled in current version of
    ... some recent changes not related to tracked issues
    ... two new chapters have been added

    <Frans> a new chapter:


    frans: one extra chapter with a summary of requirements per



    frans: another extra chapter on requirements that are deferred
    to some later time
    ... another global change relates to slight change of wording
    (standards -> recommended way)

    <kerry> alejandro: we are wroking to close the issues in the
    tracker still from barcelona

    <kerry> .... ideally now looking for external feedback

    <Linda> What was Frans saying about CRS requirements?

    alejandro: after public working draft we'll get external
    feedback that will help to refine requirements

    <kerry> ... we should try to extend the description of

    <Frans> For CRS requirements a separate meeting or
    teleconference is considered.

    alejandro: we should try to extend the descriptions of
    requirements with examples

    <kerry> ... with examples and clarifications

    kerry: any more questions on the use case document?
    ... discussion on crs in particular delayed a bit to give
    people a chance to comment

SVG for spatial: Presented by Satoru Takagi by invitation (confirmed)

    <ChrisLittle> kerry you kept droppping out on audio - is that
    me or you or all?

    <stakagi> Thank you very much for inviting to conference.

    kerry: scalable vector graphics

    <stakagi> First, I would like to introduce the strategy of the
    standardization activity of mapping on SVG2.

    <Linda> Good audio here Chris

    <stakagi> I want to fuse mapping with a web browser. Because I
    think mapping is essential function for WWW.

    <kerry> stakagi, your turn to speak please!

    kerry: satoru is not on webex but will do presentation on irc

    <stakagi> Yes I am IRC only

    <phila> we're reading you stakagi

    <stakagi> SVG2 is under standardization as a succeeding
    standards of SVG1.1 snd edition. Probably, it is standardly
    implemented in web browsers.

    <ChrisLittle> * thanks linda - i'll move nearer my router

    <stakagi> [14]https://svgwg.org/svg2-draft/

      [14] https://svgwg.org/svg2-draft/

    <stakagi> We set some policies in standardization of the
    spatial information on SVG.

    <stakagi> Provide a certain effectual result to the drawing
    function by the browser of SVG.

    <stakagi> That is, don't be satisfied with a mere metadata. The
    functionality should be implemented as a native functionality
    of all the web browsers. Besides, we consider that value of Web
    is concentrated to the web browsers.

    <stakagi> The functionality needed for Web Mapping should turn
    into a native functionality of a web browsers.

    <stakagi> That is, the functionality of Web Mapping should be
    offered without massive web Apps.

    <stakagi> We consider that massive Web Apps does not have a not
    much good effect on the interoperability of a data. Sometimes,
    it may produce a data silo.

    <stakagi> On the other hand, we believe that the functionality
    essential to such a mapping should not be a functionality only
    for a mappping.

    <stakagi> That is, we consider that the functionality it is
    often used by mapping should be generalized so that it may be
    used also other than mapping.

    <stakagi> It is because it promotes the native implementation
    to web browsers. These are the policies which we (KDDI)

    <stakagi> So far, are anything a question and comment ?

    <phila> We're reading your words, stakagi

    <stakagi> Yes

    <phila> Please continue, I am likely to have questions later

    <stakagi> Yes continue.

    <stakagi> First, we enumerated needed functionalities on the
    mapping for us and submitted the documentation which summarized
    it as a first stage draft specification to W3C as member

    <stakagi> [15]http://www.w3.org/Submission/2011/04/

      [15] http://www.w3.org/Submission/2011/04/

    <stakagi> This is our member submission.

    <ChrisLittle> +1 to general mapping migrating natively to

    <stakagi> Thanks Chris!

    <stakagi> This submission includes global coordinate systems (
    general purpose CRS)

    <Frans> I like the idea of browsers natively recognizing
    spatial data and being able to display it.

    <stakagi> and Tiling and Layerling.

    <Frans> Satoro, Well Known Text (WKT) is a popular format for
    geographic geometry. Are you looking at automated
    transformation between WKT and SVG?

    <stakagi> SVG has metadata framework

    <ChrisLittle> The OGC has active work in progress on layering
    and tiling. Is KDDI a member of OGC?

    <kerry> s/nw/now/

    <stakagi> No, currently KDDI is not OGC member.

    <stakagi> over 15 years ago KDDI was OGC member.

    <ChrisLittle> Joan Maso is Chair of Web Map Tile Service
    Standard WG, and I Chair Web Coverage Tile Service SWG

    <ChrisLittle> +1 kddi OGC member!

    <stakagi> but past OGC's member is not interested in our work.

    <ChrisLittle> past is past, now is now

    <stakagi> Yes^^

    <joshlieberman> I believe that Carl Reed, former OGC CTO had a
    fair amount of interaction with the SVG standards working
    group, but it lapsed.

    <phila> And W3C is the home of SVG, making things first class
    citiznes of the Web etc. Shall we go on ChrisLittle?

    <joshlieberman> Good to take up again, perhaps by recognizing
    some mapping use cases, e.g. dealing with geographic projection
    and feature attributes

    <phila> Do you have more stakagi or should we ask more

    <stakagi> Do you intered in Tiling architecture on SVG?

    <kerry> anyone for tiling?

    <phila> Isn't the point of SVG for maps that we can do away
    with tiling?

    <Frans> I think vector geometry tiling is a hot topic

    <joshlieberman> It is certainly a part of work on geopackage

    <stakagi> I have tiling slide


      [16] http://www.slideshare.net/totipalmate/tiling-51301496

    <ChrisLittle> OGC WCTileService has three phases. first, now is
    for pixel tile, second then point clouds, then lastly
    geometries, whichare close to SVG

    <stakagi> Tiling on SVG is (probably) much different from
    WebGIS's tiling architecture.

    <kerry> stakagi, people are speaking about interest in this
    tiling topc

    <Frans> Is [17]http://www.w3.org/Submission/SVGTL/ likely to be
    included in SVG2?

      [17] http://www.w3.org/Submission/SVGTL/

    <phila> How do you define a pixel, ChrisLittle? (CSS pixels are
    not equal to actiual pixels on the screen for e.g.)

    <Linda> I share phila's question: Isn't the point of SVG for
    maps that we can do away with tiling?

    <stakagi> Most differnt point is "non

    <ChrisLittle> Currently, Joan and I are interested in
    establishing a n-dimensional tiling architecture, to supercede
    2-D and layers

    <ChrisLittle> this may not be of interst to 2-D SVG

    <Frans> We could do away with image tiling, vector tiling is a
    different subject.

    <joshlieberman> Certainly an SVG capability to work with
    multiple coordinate reference systems as Web mapping apps do,
    would be very useful (e.g. pixel, viewport, tiling scheme,
    projected CRS, geo CRS)

    <ChrisLittle> +1 to that hierarchy

    <phila> Do you have ideas for how the SVG work and this WG's
    work can be aligned, stakagi?

    <stakagi> About our submission

      [18] http://www.w3.org/Submission/SVGTL/)

    <joshlieberman> Darn, I was going to be impressed by the

    <stakagi> we expressed that the submitted specification
    proposal should be once disassembled and it should have been
    reconstructed based on the view of the SVGWG members. It is
    because we thought that a generality increased by such
    procdess. Moreover, many of members of SVGWG are the developers
    of a well-known web browsers. And the specification which
    reached their consensus is easy to be implemented in a browser.

    <joshlieberman> So do we need to consider SVG potential as a
    spatial data format or its compatibility with spatial data (as
    a graphic format)?

    <Frans> I think SVG already is a spatial data format. Perhaps
    not geographic, but spatial yes.

    <stakagi> Yes I think so.

    joshlieberman: could we consider svg as spatial data format
    (with crs...)

    <phila> joshlieberman: Is SVG a spatial format? That's one
    perspective. Another is, is SVG interoperable with other
    spatial data formats

    joshlieberman: is svg interoperable with other spatial data

    <kerry> stakagi, can you comment on interoperability with other
    spatail formats?

    <ChrisLittle> SVG certainly made the processing chain in
    meteorology shorter

    <Zakim> kerry, you wanted to ask about CRS

    <stakagi> I think SVG is interoperable with other spatial

    <stakagi> if CRS is resolved

    <joshlieberman> Chris, is SVG used as a fully expressive
    spatial data format for mets, or a presentation format?

    <kerry> Stakagi, how does SVG handle coord systems?

    <ChrisLittle> I think various conversion tools like
    shapefile<->SVG or CGM existed

    <stakagi> The specification of a geographic-coordinates system
    on SVG1.1 is described here.

    <Frans> I think SVG will remain 2D? Most geographical formats
    are enabled for 3D

    <ChrisLittle> SVG used for both presentation and archive,
    thoughI have concerns about latter in context of SVG2

    <joshlieberman> Well, you can consider, e.g., Geoserver a
    conversion tool, but one of its output formats is SVG. It's a
    full rendering process, though, from shapefiles for example,
    requiring the addition of portrayal information.

    <stakagi> Transformation for SVG is 3D.

    <ChrisLittle> We used CGM for distribution of presentations and
    archive too, but CGM rather niche now

    <stakagi> because CSS3 uses 3d transformations.

    <ChrisLittle> CGM<->SVG very straightforward

    <stakagi> and SVG is tightly coupled with CSS

    kerry: so svg is 3d now?

    <phila> Yep. I'm just looking for a ref to SVG 3 D

    <stakagi> But geometry is still 2D.


      [19] http://www.w3.org/TR/SVG/coords.html#GeographicCoordinates

    <Frans> Consider 3D source data to be transformed to SVG

    <ChrisLittle> SVG2 has support for the 3D->2D pipeline, but is
    not strictly 3D

    <stakagi> Yes.

    <kerry> any comments onthe coords link anyone?

    <stakagi> The specification of a geographic-coordinates system
    on SVG1.1 is described here. However, geographic-coordinates
    system on SVG does not agree of the policy described so far.
    The metadata which does not influence a rendition. Only for

    <Frans> support for spherical coordinates would be great

    <stakagi> As expected, this specification is going to be
    obsoluted on SVG2.

    <stakagi> Then, we proposed the concept of the global
    coordinate system for realizing the functionality of a tiling
    and layering. The global coordinate system could be used also
    as geographic coordinate system. Arbitrary global coordinate
    systems are specified as URI. However, the spec of SVG2 does
    not have a global coordinate system yet.

    <ChrisLittle> I think SVG will not support spherical coords.
    you will have to look towards OpenGL

    <Linda> It says " RDF description of the Coordinate Reference
    System definition used to generate the SVG map".



    <stakagi> This is our proposal for "global" coordinate systems.

    <ChrisLittle> Global coord system suggests links to OGC DGGS
    Digital Global Grid system work

    <joshlieberman> Yes, that's an aspect of trying to make
    functionality that exists in OpenLayers or Leaflet a native
    browser function -- for example projecting WGS84 coordinates
    into Web Mercator for display overlay.

    <ChrisLittle> -1 web mercator

    <Frans> frans wonders how we can strengthen ties with SVG
    development in general and in the UCR doc specifically

    <joshlieberman> ...As example of a projected coordinate system
    to avoid the "stupid" aka plat carre projection.

    <kerry> satoru will be at tpac, although SVG WG is not meeting

    <phila> Should we have a session about this at TPAC then?

    <stakagi> Yes I will attend TPAC.

    <ChrisLittle> +1 to session at Sapporo, though not going.
    Jeremy can cope.

    <joshlieberman> I would suggest two lines of inquiry --
    interoperability with spatial data, and a plugin mechanism for
    more capable spatiotemporal transformations.

    <stakagi> SVG1.1's geographic coordinate systems specification
    is going to be obsoluted on SVG2.

    <Frans> Perhaps we can at least mention SVG in the UCR document
    before TPAC

    <Linda> The CRS reference topic is interesting for our CRS
    discussion as well.

    <ChrisLittle> +1 to Josh's proposed activities at some stage

    <stakagi> Because it is only for metadata. No influece for SVG

    <kerry> josh: best practice we should look t svg and

    <kerry> ... unclear how to express spatial data we need to
    learn this

    <kerry> ... and maybe motivate some svg work

    <kerry> ... sticking point is crs support

    kerry: requires looking at transformations and crs support

    <kerry> .... native mapping support is attractive but
    transformation and coords in a native implmentation is needed

    kerry: is there a way to plug in transformation mechanisms that
    exist in JS (e.g. OpenLayers)

    <kerry> ... can we suggest a way to plug in the transformation
    mechanisms we know of in javascript apps

    <stakagi> What is transformation?

    <ChrisLittle> +q

    <kerry> ....so they do not need to be in every browser but can
    be plugins

    <stakagi> latitude/longitude to X-Y?

    <Frans> Satoro, do you mean CRS is not on the agenda for SVG 2?

    <ChrisLittle> a plugin issue killed or seriiously damaged SVG
    ten years ago

    phila: it would be interesting to define a JS-aligned web api
    to do a translation
    ... OpenLayers (or similar) could enact that

    <stakagi> Probably we can't understand geo-community's CRS

    phila: geolocations API (separate group) is defining an API for
    geofencing and so on

    <stakagi> Yes I don't like plug-in or other extensions.

    phila: just define the API, inner workings do not need to be

    <kerry> satoru, crs is an hot topic in the group, that we have
    not resolved

    <Frans> I think there should be simpler level CRS definitions

    <Frans> ... we need to bridge the gap between geographical data
    and spatial data in SDWWG

    <kerry> thank you satoru!

    kerry: thanks satoru for making time

    <joshlieberman> Thanks from Josh as well.

    <kerry> ACTIONto kerry to follow up with SVG

    <stakagi> The definition of CRS is unclear in general purpose

    <scribe> ACTION: kerry to follow up with SVG [recorded in

      [21] http://www.w3.org/2015/08/05-sdw-minutes.html#action01]

    <trackbot> Created ACTION-60 - Follow up with svg [on Kerry
    Taylor - due 2015-08-12].

    <kerry> Satoru, thank you for your presentation!

    chrislittle: phila, which of the svg wg members with be in

    <kerry> Satoru, I will ensure we continue a conversation, there
    is a lot of interest in this group

    phila: doug will be there

    <stakagi> Thanks.

    <kerry> returning to webex

    kerry: back to audio

    <stakagi> I would like to understand CRS well first.

    <Linda> Any hotel suggestions for Sapporo?

    kerry: reminder: put your attendance on the wiki for TPAC

    <ChrisLittle> I did!


      [22] https://www.w3.org/2015/spatial/wiki/Attending_Sapporo_F2F

    <stakagi> The hotel in Japan is mostly narrow.

Best Practice Issues as raised by Jeremy

    <Payam> Jeremy's email:


    kerry: we ran a bit out of time
    ... i might coordinate with payam about trying to find


      [24] https://www.w3.org/2015/spatial/wiki/BP_Consolidation



    kerry: relating topics in the document with web architecture
    and use cases

    <Payam> Jeremy's email:


    kerry: thank you everybody, esp. to Satoru

    <AndreaPerego> Thanks and bye

    <Alejandro_Llaves> thanks, bye"

    <billrobe_> thanks bye

    <Linda> bye

    <Frans> Goodday!

    <BartvanLeeuwen> thx bye

    <joshlieberman> Thanks bye

    <kostas> thanks bye!

    <ChrisLittle> bye and thanks

Summary of Action Items

    [NEW] ACTION: kerry to follow up with SVG [recorded in

      [27] http://www.w3.org/2015/08/05-sdw-minutes.html#action01

    [End of minutes]
Received on Wednesday, 5 August 2015 23:58:46 UTC

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