Online Maps with OpenLayers

Organized Excerpts from chat on Jan 27th (full chat is attached)

Getting Started

 

<trekr5> http://wiki.openstreetmap.org/wiki/Beginners'_Guide

 

<berniejconnors> @rrosso here is a quick video I just made of digitizing a building: http://screencast.com/t/MDRtnaCHTbz

<berniejconnors> The video is only 4.6 MB I used Jing to make the video

 

<introvert> wwilson: how do I tell you what I am looking at?

<ndoiron> @introvert on OpenStreetMap click Permalink to link to your view

 

Editing the Map with Potlatch 2

 

Once you register an account, use https://www.openstreetmap.org/user/mp/account to set Preferred Editor to Potlatch 2, then click Save Changes at the bottom of the page Now as you explore OpenStreetMap, you can click the "Edit" tab to make changes.

 

<trekr5> @ndoiron what's potlatch2?

<Sharonm> @trekr5 The default editor on the Web site is potlatch 1

<Sharonm> but you can change it to potlatch 2

<Sharonm> which does indeed seem easier, as @wwilson suggested

<berniejconnors> Potlatch is loaded when you click the "edit" tab on the OSM website

<alex_> Potlatch offers more options

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<alex_> nick, with Postlatchthe images are better (at least the zoom), and you can edit the vertices (moving) or adding more as wwilson said

 

<rrosso> How do I get a permalink that shows my edits?

<ndoiron> http://www.openstreetmap.org/user/rrosso/edits

 

Satellite Maps can Help, but not all are Open

<berniejconnors> @rrosso you don't collect coordinates from other online maps

<berniejconnors> @rrosso you either collect GPS tracks with a handheld GPS or you digitze streets from the air photos that are displayed in the OSM editor

<ndoiron> @rrosso you draw it in the Edit tab

 

<wwilson> @introvert Satellite or aerial photography.

<wwilson> If you're using the online editor, they'll automatically display the best they have in your region.

<wwilson> US is mostly Yahoo and Bing.

<wwilson> @trekr5 There are other imagery providers outside of the US.

 

<rrosso> I'm confused about what we can/can't do with Bing/Yahoo mapsUsing lat/long data from Bing is copyright infringement, someone said.

<ndoiron> @trekr5 OpenStreetMap is open for others to reuse, sell, and download The references have to give permission or be open maps themselves

<rrosso> So what did Bing just start allowing people to do a couple months ago that enables one to use it with OSM?

<ndoiron> @rrosso  They allow you to trace roads from their images into OpenStreetMap http://www.bing.com/community/site_blogs/b/maps/archive/2010/11/23/bing-engages-open-maps-community.aspx

<ndoiron> @rrosso  the best tracing program to start with is Potlatch, which is on the OpenStreetMap.org site

 

<rrosso> @trekr5, @ndoiron: is Bing better than google maps for that sort of thing?

<ndoiron> Google doesn't allow it

<rrosso> @ndoiron: I guess that makes Bing better for it, huh? :)

 

Adding Tags and Labels

<alex_> Just register to OSM, make a little editHow do you label way streets?

<ndoiron> alex_: I did some Googling, maybe you can do oneway=no ?   http://wiki.openstreetmap.org/wiki/Talk:Key:oneway

<alex_> Thanks Nick, it worked fine (once you know what to do)

 

<Sharonm> Am finding OpenStreetMaps a little frustratingI just tried to add a post office, and it's asking me for the post office reference numberNo idea how to find that, USPS Web site doesn't have it that I can see.

<wwilson> @Sharonm I don't think tags like that are mandatoryThough they are, of course, useful.

<wwilson> @rrosso Not sure it has meaning in the USSee: http://wiki.openstreetmap.org/wiki/Post_office

<wwilson> Remember that OSM is international, so not all tag are applicable in all countries.

<berniejconnors> Yes OSM is international I had a hard time calling a soccer field a "pitch"

<wwilson> None of the post offices I've looked at in the US have ref= set, but I'm new to this, so who knows?

 

<introvert> ndoiron: is it OK to identify (with what?) early childhood buildings for a particular service provider?

<ndoiron> @introvert Tag the school as an "amenity" that's type "school", and you can add more tags like grade level

 

<ndoiron> for people who've used OSM longer :  do the tags and values have a good standard?  Or is it just important to put what you know

<berniejconnors> I find there is usually a core of OSM users in your community / country who try to suggest standards for tagging.

<alex_> I think your localiy knowledge is what counts

<berniejconnors> Personally I find adding the geometry is the most important

 

To Fix and Add Streets and Buildings

<berniejconnors> @rrosso here is a quick video I just made of digitizing a building: http://screencast.com/t/MDRtnaCHTbz

 

<Sharonm> How do I add a street? There's a new street in the area, I see it on the image but it's not on the map yet.

<alex_> sharon just click on one end of the street and keep adding points, finishing with a double click, then add data in the left panel

<berniejconnors> It is best to save after just a few edits becuase it can be slow when you have made many edits

 

<Sharonm> Not sure how to add geometryI'm just adding points of interest, which is the knowledge I already have -- adding points to maps.

<alex_> Sharonm just click on the map without dragging any tag, then you should add more points, and double click to finish the line

<Sharonm> What's easy to start with?

<berniejconnors> @sharonm  A building footprint or a short residential street is a good easy place to start.

<wwilson> @Sharonm There are plenty of spots where if you compare the roads with the photos, it's clear that the OSM data is misalignedJust dragging stuff into the right spot is an easy way to get started.

<wwilson> Don't know if that's a problem in your area, but it's really bad in, for instance, SoCal, Arizona, and New Mexico.

 

<Sharonm> @ndoiron But I only need to reclassify part of the way How do I select just part of it?

<Sharonm> I'm trying to select just a piece of a way but can't.

<ndoiron> in the bottom right, do you have a scissors?  it can split the way and then you could rejoin the two halves

 

Deleting Points

<DoRight> @bernie How do you kill a point?  I clicked by mistake in the editor and couldn't get it to stop.

<rrosso> @DoRight: I did the same thingI think you can select it again and hit the red X in the bottom-right toolbox to delete it.

 

If there's already a high quality map, what should I edit?

<introvert> ndoiron: what if I don't see anything to edit?

<ndoiron> you can look at more places that you know, and add building outlines or more obscure things

<berniejconnors> introvert: It is not important to know the name of the building right now Just digitize the outline You  or another user can add the tags later.

<berniejconnors> introvert:  Mappers from all over the world digitized the streets of Haiti following last years earthquake Most of them did not know the street namesBut eventually somebody added the street names.

<berniejconnors> introvert:  Don't sweat it - just give it a try What ever you do can be undone.

 

Making Interactive Mashups (later)

<trekr5> @ndoiron are you going to show us how to create a basic mashup using OSM data in this course?

<ndoiron> @trekr5  yes, interactive maps are next after OSM

<ndoiron> @trekr5  you can see an example OSM map at jsfiddle.net/UAxun/2/

<DoRight> or now http://jsfiddle.net/DoRight/pNYQH/2/

<trekr5> @ndoiron so is jsfiddle another type of editor that you can use with OSM?

<ndoiron> @trekr5 jsfiddle helps you make websitesOnce we're done building the underlying map from OSM, we can add interactive things with OpenLayers

<DoRight> @trek5 no it is a code tester You add your html and js and it gives you a map See my link above and I would be glad to answer any questions on it I used the one mentioned in the forum as the basis for mine.

<trekr5> glad i'm taking this courseit's very interesting

 

Communication and Online Help

<anteaya> ndoiron, will you be available on this channel during non-meeting times?

<DoRight> How do we get a copy of what went on?

<ndoiron> yes, I'll put all the tips, videos, and questions together

<ndoiron> @anteaya I'll be on the channel more often, and you can go to the Forums section as well

 

Assignments / Tasks

<trekr5> should we have completed the assignment - adding point of interests to OSM map - before we come to this class?

<ndoiron> @trekr5   nope we're signing everyone up now had you used OSM before?

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<rrosso> Do we have an assignment before the next session?

<ndoiron> @rrosso if you're interested in adding more complex things, you can look up your country / local page on the OSM wiki, or helping others map