[udig-devel] loading browser-based map sites in udig as base/background layer?

[Jody Garnett]

Eric Jarvies wrote:
>> A license agreement.
>
> i just need a way to overlay my shapefile(s) atop sat images, so i can 
> make visual references for the purpose of denoting whether or not 
> there is construction/structures atop a given section of land, if 
> certain elements/landmarks are indeed there, and tasks along these 
> lines.  purely for visual reference for the sake of aiding me in 
> performing various overlay vector-based tasks.
Cool; you want to try the Nasa World Wind servers? It may be exactly 
what you needed...
Follow the walkthrough 1 instructions to add my community plugin to your 
eclipse and they will show up in the catalog.

>> I think you can get a yahoo id of some sort and armed with that we 
>> could grab images. I know that the open street map project managed to 
>> make arrangements along those lines.
>
> programmatically, what would it take(time and otherwise) to implement 
> openlayers into udig, wherein the controls(zoom, pan, etc.) are moved 
> off screen/map and onto/into their own buttons/controls.
I am not sure at this time; depends how well you can invoke javascript 
on a embeded mozilla browser. Some research is needed ... but honestly 
it sounds like you want a web application at this stage?

> In addition, adding an easy 'add map site' feature, affording the user 
> the ability to enter the respective info for the respective 
> site(openstreetmaps, yahoo, google, etc.).  and finally, having it so 
> that it is the bottom/back/background layer in the layer stack, 
> allowing other layers to be loaded atop, like shapefiles, etc., 
> wherein the top layers conform to the zoom(scale) and projection of 
> the background map-site, thus allowing the user to easily pan and zoom 
> in and out, whilst editing his/her top-side vector layers, and also 
> being able to lock-down the site-map background, whilst being able to 
> move the top-most layers around freely(for alignment, like scale, 
> move, skew, etc. of any top vector layer, as to properly align with 
> said web-map view ... we all know that our maps never line up with 
> their maps ... like in google, roads can be several meters off).

> udig is a browser(amongst other things), correct? 
Not really - uDig is an application. You can embed a browser widget into 
it - see the "Web" view as an example - what is being shown is a simple 
web page, clicks on this web page are listened for and if you click on a 
capabilities document udig will open it up.
> google, yahoo, etc. have no restrictions as to the type of browser 
> that can display those sites and their respective 
> content/data//maps.   everything would be served up the same way for 
> all intents and purposes.  
I am afraid what they all want is the ability to track the user; hense 
the javascript api.
> by implementing openlayers into udig, and moving the controls 
> off-screen and onto their own buttons/menus, this would essentially 
> empower the udig user, and again, would not serve to violate the 
> rights of any mark or copy holder.
I see what you are saying; sounds a bit shaky to me. On the technical 
side of things the embeded browser is a full widget; not sure if we can 
overlay a transparent window overtop of it.
> it should be thought of as a means by which one can confirm his or her 
> maps for easy export to kml, etc, for use on these 3rd party map 
> sites.  being able to load up one of the maps sites, and then load 
> your content files atop, you can take a visual look around, make the 
> adjustments/changes that are needed, and then export your content to 
> the respective site/program format for use in a mashed-up environment.
I was going to handle a similar problem to this using context documents 
(drive open layers and udig from the same context document - subst the 
google maps layer with something on sound legal footing, and then 
exporting the context document to the web, possibly publishing the 
shapefile to a geoserver or mapserver if needed).
> problem here is resolution when zoomed in close. it's bad :(
The joy of free data; what application did you need to this result in? 
Yahoo is pretty lax about the restrictions. Also you can totally set up 
an image mosic with a pretty amazing level of detail if you have some 
disk space to burn.
> i would like to see this implemented in udig, but alas, i am a 
> developer, not a programmer.  so, if anyone else would be interested 
> in performing the required work to make this feature-set a reality, i 
> would indeed do my part in gui/button/etc. design, copy, and financial 
> contribution.  l see no heavy lifting here, and everything seems 
> straight forward to one who is a competent programmer, familiar with 
> udig's trunk/code-base.  does anyone else see the value in this 
> feature-set?
I will bounce the idea off Paul, see if the idea is sound enough to send 
you a quote. Sorry to be hesitant on this one, I know the various data 
providers would love to sell you high quality background imagery; as 
such they are very careful about what they allow google and yahoo to 
"give away" for free.

Cheers,
Jody