- From: Phil Archer <phila@w3.org>
- Date: Wed, 5 Aug 2015 15:06:42 +0100
- To: SDW WG Public List <public-sdw-wg@w3.org>, Satoru Takagi <sa-takagi@kddi.com>
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
Attendees
Present
Kerry, stakagi, kostas, aharth, Linda, Payam, Kostas,
ChrisLittle, phila, SImonCox, billroberts,
Alejandro_Llaves, frans, BartvanLeeuwen, AndreaPerego
Regrets
Lars Svensson, Rachel Heaven, Ed Parsons
Chair
kerry
Scribe
andreas harth
Contents
* [3]Topics
1. [4]Welcome new members
2. [5]Use Cases and Requirements: Editors' stocktake
report
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
spec
<stakagi> Hello!
Use Cases and Requirements: Editors' stocktake report
kerry: update on document
... frans and alejandro are both here
<Frans>
[11]http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirement
s.html
[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
document
... some recent changes not related to tracked issues
... two new chapters have been added
<Frans> a new chapter:
[12]http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirement
s.html#RequirementsByDeliverable
[12]
http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#RequirementsByDeliverable
frans: one extra chapter with a summary of requirements per
deliverable
<Frans>
[13]http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirement
s.html#DeferredRequirements
[13]
http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#DeferredRequirements
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
requirements
<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)
decided.
<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
submission.
<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
browsers
<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
questions?
<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
<stakagi>
[16]http://www.slideshare.net/totipalmate/tiling-51301496
[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
arithmetical-pregression".
<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/)
[18] http://www.w3.org/Submission/SVGTL/)
<joshlieberman> Darn, I was going to be impressed by the
emphasis
<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
formats
<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
formats
<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.
<stakagi>
[19]http://www.w3.org/TR/SVG/coords.html#GeographicCoordinates
[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
geospatial.
<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".
Interesting....
<stakagi>
[20]https://www.w3.org/Graphics/SVG/WG/wiki/Proposals/Global_Co
ordinate_Systems
[20]
https://www.w3.org/Graphics/SVG/WG/wiki/Proposals/Global_Coordinate_Systems
<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
rendering.
<kerry> josh: best practice we should look t svg and
expressivness
<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
meanings.
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
detailed
<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
anyway
<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]
[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
sapporo
<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
[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:
[23]http://lists.w3.org/Archives/Public/public-sdw-wg/2015Jul/0
097.html
[23]
http://lists.w3.org/Archives/Public/public-sdw-wg/2015Jul/0097.html
kerry: we ran a bit out of time
... i might coordinate with payam about trying to find
volunteers
<Payam>
[24]https://www.w3.org/2015/spatial/wiki/BP_Consolidation
[24] https://www.w3.org/2015/spatial/wiki/BP_Consolidation
<Payam>
[25]https://www.w3.org/2015/spatial/wiki/BP_Consolidated_Narrat
ives#Consolidated_narratives_.2F_common_themes
[25]
https://www.w3.org/2015/spatial/wiki/BP_Consolidated_Narratives#Consolidated_narratives_.2F_common_themes
kerry: relating topics in the document with web architecture
and use cases
<Payam> Jeremy's email:
[26]http://lists.w3.org/Archives/Public/public-sdw-wg/2015Jul/0
097.html
[26]
http://lists.w3.org/Archives/Public/public-sdw-wg/2015Jul/0097.html
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]
[27] http://www.w3.org/2015/08/05-sdw-minutes.html#action01
[End of minutes]
__________________________________________________________
Received on Wednesday, 5 August 2015 14:07:35 UTC