31

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.


24

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.


16

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 ...


16

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 ...


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

In QGIS you should be able to filter your data with an SQL expression in the Query Builder dialog. Just right click your layer in the table of contents and select "Query" ("Filter..." in the more recent versions).


10

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 ...


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

You can set the page background to transparent by creating a transparent symbol and setting the page background to use that symbol: transparent_fill = QgsFillSymbolV2.createSimple({ 'outline_style': 'no', 'style': 'no'}) c.setPageStyleSymbol( transparent_fill ) There's also a few other things wrong with your script: First, mapRenderer = iface.mapCanvas()...


8

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. But ...


8

Leaflet's GeoJSON uses by default a smoothing factor which eliminates less important points. Pass {smoothFactor: 0} to L.geoJson as an option to achieve a more appropriate overlap.


8

There are two issues you have to consider: Whether your data has spatial index or not. If not, then try to create a spatial index to your data. The spatial index can improve the speed of rendering your data in QGIS. To create spatial index, go to layer properties -> General tab -> Create Spatial Index, as you can see below: OR: You can create ...


8

You're right, it is a debugging setting. It can be handy for troubleshooting labeling issues. It's next to the pull-down for the labeling list so you may have activated it by mistake. In my version, you have to specifically check on "show candidates" to enable this; perhaps in your version this is checked by default, so dismissing the dialog with OK ...


7

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


7

The so-called "multiresponse GeoJSON object" is not valid GeoJSON. Split the data before instantiating the Leaflet GeoJSON layers, e.g.: // Assuming that you've already fetched the data off the network var data = { roads: { type: "FeatureCollection", features: ..... }, pois: { type: "FeatureCollection", features: ..... }, ....... };...


7

Make sure that under Settings -> Options -> Rendering you have "Render layers in parallel" checked.


7

Try setting the thickness of the borders of the polygons a bit smaller, in millimeter and maybe change the join style. If you set it too high and on bevel or rounded, the rounded factor you can set in the layer properties can be seen. You can also choose to remove the borders of your polygons (style "no-pen") To make sure what will be the rendered layer, ...


6

For anyone who is still having this problem, in QGIS 2.10 you can go to Settings > Options > Rendering, and change the Map update interval to be larger. If QGIS can render all of the layers in less than this amount of time, it will update the whole canvas at once, which gets rid of the blinking. If it cannot update all the layers before this interval passes, ...


6

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 ...


6

As a workaround you may choose "Solid Line" option for borders, set the same colour to borders and fill of the polygon and set border width to 0.0 .


6

That's possible using symbol levels - just like when creating a road style for linear features. Here an example using Natural earth countries: it looks as if they have been dissolved - but it is only a rendering effect. The outline color and width are controlled on the symbol layer level: click on the blue symbol and there will be an option to configure ...


6

I am now using Tangram to display my tiles, Tangram allows me to parse the composite response with no issues at all, it can identify the layers with just the name I supply, and it has good documentation and support.


6

Not sure this is what you are really after, but you can use a single line with a different symbolisation to create the appearance of two parallel lines. Starting with a 1.1 km line in CRS 3857 (metric, pseudo-Mercator as per Google and other web services): In properties, add another symbol layer (so you see two lines). Set the width of each line in map ...


5

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


5

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 ...


5

I'm afraid the answer is: You can stop QGIS from blinking by funding a developer to implement a non-blinking version.


5

The problem was almost certainly that you had a stray bracket: renderd[8967]: An error occurred while loading the map layer 'default': Shape Plugin: shapefile '/usr/local/share/world)boundaries/shoreline_300.shp' does not exist (encountered during parsing of layer 'world' in map '/home/oleg/src/mapnik-style/osm.xml') Note: world ) boundaries Can you close ...


5

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.


5

Check whether you accidentally set a limit on how many features might be labelled. There's a check box under the layer properties | labels | Rendering. It reads "Limit the number of features to be labelled to". See the image:


5

There are different issues surfacing here Rendering on screen vs rendering to an image The signal mapCanvasRefreshed is emitted repeatedly while the canvas is being rendered to screen. For on-screen-display this gives a quicker feedback which can be nice for a user to see something going on or help in navigation. For off screen rendering like saving to a ...


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