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17

Here is excel sheet in Google Docs from GeoSolutions team (http://geo-solutions.blogspot.com/2010/12/estimating-time-and-space-required-to.html) https://spreadsheets4.google.com/ccc?key=tyCIm7rz8753DUGC9FyOXaw#gid=0


13

You can write a simple shell script and use gdal_translate utility to chop the tiles. On Mac, get the GDAL build from here. On Windows,the best way to get GDAL is via the OSGeo4W installer. In the following script, you need to replace following things XDIM and YDIM with your source jp2 X and Y dimensions gdal_translate with the actual path on your system ...


12

For a simple way to do this starting with QGIS you could use QGIS Mapserver which can serve maps that you design using the normal QGIS interface. Alternatively you might want to go with GeoServer which is Java based and probably easier to install. Since both programs serve maps using open standards if you start with one and need to switch later there is no ...


10

This somewhat exists - here's a page of the various converters available. Exporting CartoCSS from other tools requires both mangling the native format and normalizing differences between how they treat data & the capabilities of the renderer.


9

WorldImage is for accessing regular images that have a world file associated with them. ImageMosaic is for serving up multiple raster files (usually organized into tiles) as a single layer. And ImagePyramid is essentially a multi level mosaic in which higher levels are generalized versions of lower levels. Usually people don't serve up world images ...


9

There is a very good web site for beginners about OpenStreetMap world focused on people coming from other mapping services that could fit your question: http://switch2osm.org/serving-tiles/ But if you want to create some tiles to be served offline something like http://www.maptiler.org/ but it's focused on raster data. If I had to do this I would probably ...


9

I would recommend looking into TileMill which is made by the same people that were workign on Maps On A Stick. TileMill was either part of Maps On A Stick, or is what Maps On A Stick became - something like that. I forget the connection. Anyway... TileMill will let you load geographic data, style it how you like and then create a set of PNG map tiles for a ...


9

Definitely open to adding more features/functionality to my QGISTileMillExport plugin (as well as adding it to one of the plugin repos for easier installation once it's a bit more mature). I stubbed it out as a proof of concept for my own use a few months ago. As for workflow, I saw it as a way to bridge between data/rough styling in QGIS and final ...


9

Google has built their own vector map rendering engine based on OpenGL ES version 2: https://developers.google.com/maps/documentation/android/start#requiring_opengl_es_version_2 Here's a link about OpenGL ES on Android: http://developer.android.com/training/graphics/opengl/index.html OpenGL lets you leverage the underlying power of the GPU and get ...


8

being able to show categorized polygons in a thematic map (- if possible, it would be nice to get popups or to be able to retrieve attribute information - but that's highly optional) I would prefer to do most work (styling, etc) in QGIS OSM as base map would be perfectly fine All this can be done within QGIS and the ogr2layers plugin. The ...


8

In other implementations (as in, our implementation) this is done with palette modification; you can quickly recolor a PNG image without touching the actual data, if you know the full original palette. Google doesn't do that; they likely have a tile-based database and tiles of vector data that are rasterized on the fly.


7

As tile caches are pregenerated map images, you will really be testing the underlying map / wms / image server. Unless you are testing against a pregenarated cache, in which case you are testing the web server itself (Apache / IIS etc.). Stress testing for websites is often done using JMeter. There was a recent series of posts on using JMeter at ...


7

The tile image is already in EPSG:3857. Why not just create a world file to reference it? http://en.wikipedia.org/wiki/World_file For the tile that covers N. America at zoom 1, you'd be looking at the following worldfile contents: 78271.517 0 0 -78271.517 -19998372.6 19998372.6 Where those numbers came from: Line 1: width of an image pixel in world ...


7

One note: I recommend mod_wsgi over mod_python. And it is important to either use Apache prefork with mod_python or (ideally) mod_wsgi in daemon mode with threads=1 and processes=N (where N is best matched to number of logical processors). mod_wsgi in daemon mode can be used with either Apache prefork or worker. The reason for this is that TileCache caches ...


7

I'd recommend using TileMill to generate the tiles, it can save them out to a variety of formats including as mbtiles bundles which can be used for offline applications. Tilemill will give you cartographic control over the maps, and produces beautiful results. Alternatively, you could download the styled data from Cloudmade, the .img files should be full ...


7

Nokia owns Navteq (acquired in 2008 for $8.1bn) 4 Tile Servers with pre caching 1.maptile.lbs.ovi.com/maptiler/v2 2.maptile.lbs.ovi.com/maptiler/v2 3.maptile.lbs.ovi.com/maptiler/v2 4.maptile.lbs.ovi.com/maptiler/v2 They do generate their own tiles from this vector data into raster tiled png format (256px x 256px) files one example is ...


7

Before going down any more laborious paths, the simplest option is to reduce the geometry. What are your source datasets? How did you simplify them? How much did this reduce the geojson file size? If you are confident that you have done all you can on the above, then the lowest hanging fruit of your options is Serve the geojson file gzipped, ...


6

Do you have to use OSM? or would a similar but smaller vector dataset work for you? If so consider Natural Earth (http://naturalearthdata.com) which has nice 1:10M scale coastline, land area, ocean, river and lake layers. You could then use GeoServer or MapServer locally (or on a remote server) to create your tiles at any depth you need with any of the usual ...


6

The degradation of performance depends on the client's machine - how much memory is available to render DOM elements in the browser, and how fast the CPU can work to redraw these elements when the map changes. In my experience 144 tiles (each of which will be a new DIV element) should be fine. IE handles several hundred DIVs and FireFox a few 1000 ...


6

TopOSM has terrain tiles - though limited coverage (US Only) http://www.toposm.com/us/ Full Details http://wiki.openstreetmap.org/wiki/TopOSM All the Rendering and Source files are available http://svn.openstreetmap.org/applications/rendering/toposm/ License is the same as Open Street Map OpenStreetMap Data is available under the Creative Commons ...


6

Mike Migurski (of Stamen Design) recently made a major new open terrain map: details on his blog and I put up a quick map viewer for it. It does terrain relief shading with various DEM sources combined with roads, labels, etc from OpenStreetMap. The source code to generate the map is on GitHub.


6

Another option is TileMill -- it supports tiling, interaction and cartography in an easy to use web-based interface, including style definitions in a proto-CSS language called cascadenik. Using TileMill, you can crank out mbtiles files which can be consumed with something like TileStream. That said, there are still some tricks with deployment of the mapped ...


6

you can use maptiler and upload the file structure in your SDcard. Then add a TMS layer and set the getURL parameter to a function that return an image from SDcard: var mapBounds = null; var mapMinZoom = 12; var mapMaxZoom = 16; var tmsoverlay = new OpenLayers.Layer.TMS( "TMS Overlay", "", { // url: '', serviceVersion: '.', layername: '.', type: ...


6

I have written a tutorial on exactly this problem that you may find helpful. Basically it boils down to using gdal_translate, gdal_merge and gdal_retile so you will need to have installed GDAL. Either use apt-get install gdal or the osgeo4w installer


6

Leaflet's default projection is EPSG:3857, also known as "Google Mercator" or "Web Mercator" and sometimes designated with the number "900913". This projection is what most slippy tile based maps use, including the common tile sets from Google, Bing, OpenStreetMap, and others. You can easily use this projection in QGIS by selecting "Google Mercator ...


6

For starters, that's 525 mega-pixels uncompressed, so the 3.8MB number isn't very useful in thinking about the complexity. All these pixels have to be re-sampled to generate the different tile levels. It's a lot of work. It's also incredibly I/O intensive, so it doesn't matter how more cores you have unless you also have a lot of disks with separate ...


5

Another api that you can query instead of google's is the US Geological Survey Elevation Query. Information about their service can be found here: gisdata.usgs.gov/XMLWebServices/TNM_Elevation_Service.php A request looks like this: ...


5

You can generate your own using Maperitive: generate-relief-igor command generate-tiles command A sample hiking map using such tiles.


5

I decided to provide some information on which way I finally went for my tiled map service. Pure JavaScript and GeoJSONs weren't a solution, because I have to handle roughly 40k polygons and 33k points. So I went for tiling. Oh, and I still don't have a access to root server, so I can't set up GeoServer or something similar (wouldn't be financially feasible ...


5

It is possible to generate tiles using python console, you can read about it here. Keep in mind, that you might need to modify the script. However I would encourage you to use mapnik for generating tiles, as above mentioned qgis script did not work well for me. Styling map is easy with xml for mapnik, you will not have any trouble with it. Some ...



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