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25

Any old video card will work for the 2D display functions. The video card's 3D capabilities only come into play when using specific 3D GIS features such as ArcScene or ArcGlobe in ArcGIS Desktop. If you aren't planning on doing 3D visualization then it does not matter one bit. I would spend the extra money on an SSD instead.


14

The OpenStreetMap .osm XML data type can be parsed and rendered in a number of software packages. For a somewhat turnkey custom map tile drawer, I suggest: http://tiledrawer.com --- a product that uses Amazon's EC2 and by Michal Migurski -- who provides other pointers in this thread :) You might also check out "Build your own OpenStreetMap Server" ...


14

I used to benchmark cards against ArcView performance 10-15 years ago. A decent 2D card would perform at least as well as the high-end 3D cards, exactly as expected: panning and zooming around in a map doesn't use the 3D capability. I don't think this has changed any. (Two years ago, when fine-tuning a new workstation, I benchmarked the low-end Nvidia NVS ...


12

Speed Tests There are some very speed tests of shapefiles versus database (PostGIS) for MapServer in this presentation (from 2007). In summary: For a dataset of 3 million features running requests for 30 features one after another PostGIS was faster than shapefile (although this may have since changed by a fix to reading the shapefile index) For a ...


11

Check out the Generalizer plugin, it should do what you want. The plugin has smoothing options which work quite well. It doesn't change how your lines are rendered but instead makes a new shapefile with smoothing (or simplification/generalization) applied.


9

I was able to get this to work: http://dl.dropbox.com/u/2654618/la_goog.html Here's a screenshot: As I said in my comment, I reformatted your raw data. I did this with some python and a little hand-jamming. The resulting JSON is here: http://dl.dropbox.com/u/2654618/la_geom.json That's the Esri JSON format for a polygon. The link above converts the ...


9

Contrary to what dariapra says, my experience in developing Maperitive tells me that the greatest bottleneck is in actual loading of the data before rendering. It all very much depends on how large the overall stored dataset is and how large is the dataset you are trying to render in one go. If you can load it all up into memory, then shapefiles are probably ...


8

Using QGIS + GRASS plugin: Add the Grass toolbar from the "Manage Plugins" window. Your lines will need to be a grass vector, so convert them into a new or existing GRASS mapset. From the GRASS toolbar, select GRASS Tools... Look for the module: v.generalize (WIKI tutorial here) You can then choose several different generalizing algorithms: Note the ...


8

Two possibilities, depending on how much of the OSM data itself you want to edit. One is to host your own OSM server, with a copy of the data that you can freely edit. The software for this is known as "The Rails Port", can be found here: http://wiki.openstreetmap.org/wiki/The_Rails_Port Another is to use OSM's tiled cartography as a background for your ...


7

If you just want a nice pre-rendered basemap and you are using QGIS, try the "OpenLayers plugin" from the Sourcepole repository. This plugin allows you to load in many different pre-rendered basemap image layers including OpenStreetMap, Google, Yahoo, and Bing. If you are using QGIS 1.6, be sure to check on the "Enable on the fly CRS transformation" option ...


7

Map creation is divided into several steps: entering the geodata (which are points, lines and polygons with appropriate tags) styling (specify feature appearance on the map) rendering into a raster image (transform geodata and style into an image using rendering software) You would want a tool that does all the quirks for you behind an easy to use UI. ...


6

You can render from POSTGIS with OSM data in 3D http://wiki.openstreetmap.org/wiki/OSM-3D NOTE: "Preparing OSM data to be viewed in OSM-3D requires a lot of preprocessing steps which are done on GIScience's servers." see the ZIMBA server http://wiki.openstreetmap.org/wiki/OSM-3D#Servers


5

Use the same method as you have above but use the undocumented 'TextSymbolizer' Rotation (orientation) http://trac.mapnik.org/changeset/1783 Here is another technique (Map Rotated see North Arrow - Text remains horizontal) http://ancalime.de/rotated.html


4

Try Maperitive. You can export larger areas of OSM Web map of your choice and you can even render your own using OSM vector data and a custom stylesheet. And it's much easier to use than Mapnik. Here's a sample of a large CycleMap export: And here's in original size: http://www.flickr.com/photos/breki74/4457435423/sizes/o/in/photostream/ Note that large ...


4

As far as I understand, you want to make Thematic Mapping with python and svg. you can find very good tutorial here about How to Make a US County Thematic Map Using Free Tools. i hope it helps you...


4

Your question isn't 100% clear but I assume you want to create map sets based on your 50 vector layers. This is quite easy using Atlas in QGIS. There used to be a brilliant plugin for creating the coverage layer for Atlas but that has not been ported to QGIS 2 sadly. However, it sounds as if you know your xmin, ymin, xmax, ymax extents for the 30 maps, so ...


4

Without seeing your code this is generally the wrong way to do this. You should use QgsVectorLayer::setSelectedFeatures to select features in one go. ids = [feature.id() for feature in forselection] layer.setSelectedFeatures(ids) or with some long loop: ifs = [] for feature in process: ..... #do some other stuff ...


3

Which program will you use for rendering? This may influence the results. Anyway, having a shapefile with a spatial index (eg http://mapserver.org/utilities/shptree.html ) which is used is often the fastest technique. Apart from that: it depends on you application, but caching your rendered results is often much more useful for improving performance.


3

The default OSM tiles are in a "Google tiling" format these are called Tile Map Service (TMS). At the moment, you can't use QGIS for TMS. But you can access OSM derived WMS by looking at other 3rd party service. Some are linked here: http://wiki.openstreetmap.org/wiki/WMS#Public_WMS_Servers


3

There is a simpler option for you to play around with Open Street Map data in OSM format. You can try out FME from Safe Software (www.safe.com) For more information you can read about OSM support here: http://blog.safe.com/2010/03/sharing-your-data-on-openstreetmap/ I have used FME a couple of times to create demo datasets for training for my region using ...


3

If you are looking for a good custom map-editor, then have a look at OCAD, it's a professional map drawing software. There is an older version available for free on the download page. It doesn't have any special support for OSM, but you can always use an image exported from OSM as a background.


3

Assuming that your geometries in PostGIS actually represent the true lat and lon of your locations. e.g. x value = lon and y value = lat: I see a few weird things: You have defined an output projection that is geographic, but with units of meters. Is this what you really want to do? I think that with Google, you either use a geographic spatial ...


3

It sounds like you need to check your conversion process from OS data to EPSG:4326. As whuber wrote in the comments - are coordinates imported into PostGIS in the correct order? I would guess that they are incorrect in the database itself rather than related to MapServer as your map file seems fine (update: or not. See David's answer, although this would ...


3

Suggestion: Use the OpenStreet Map Static API It is easy to add your own content without all the fuss of download and self-rendering if you just want the OSM Tiles with your walking routes Very Basic Examples of OSM tiles with Paths (lat/lng values) on Red Markers ...


3

Here are some links: http://www.geofabrik.de/media/2010-07-10-rendering-toolchain-performance.pdf http://www.geofabrik.de/media/2012-09-08-osm2pgsql-performance.pdf another point: split data to more tables: the less objects to filter, the faster the rendering


3

I've run QGIS on machines older than that. You could try filtering the results to the state. Right-click on the layer entry, and choose "Query". You can then filter to the state of interest. Keep in mind that, depending on which PLSS dataset you're dealing with, it can be a lot of lines to render, especially if your data goes down to the ...


3

The qgis.utils.iface (QgisInterface class) object is an... "Abstract base class defining interfaces exposed by QgisApp and made available to plugins" Basically, that interface is available to attached scripts (e.g. plugins) while QGIS app is running. I'm not an expert on this, but it looks like you are using the QGIS Python bindings to directly ...


3

This error occurs always when you initialize the map in invisible part of the website (ie: ). I had the same when working with jQuery accordion. No matter if it is OpenLayers or Google Maps API v3. I think it is a bug from google. As far as I remember I solve it by initialization of map during tab opening


3

I think it would depend on your needs and available resources. You can use both a map server and a tile server. For example, Geoserver comes with Geowebcache, a tile server. I know that a server map use spatial data from a DB, it generate image that can be read by client map library (openlayer ...). For example if I have a shapefiles and I don't need ...


3

Finally figured out what was going wrong when I fired up Inkscape to take a look at the details of the SVG files. They weren't vector graphics; they were raster images embedded in the SVG format. Fortunately, they were pretty simple, and I solved the problem by making my own - real SVGs this time. So moral of the story: GeoServer doesn't like to render ...



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