Linked Questions

72
votes
11answers
37k views

What Makes a Map be classed as Badly Designed?

A poorly designed map can not only look visually unappealing, but can convey the wrong message, which could lead to bad decisions being made. I would like to ask people to post examples (that are in ...
59
votes
7answers
13k views

Creating Vector Polygons with rendering performance like GISCloud?

I have been looking for a solid solution which would allow me to create a web map and overlay vector polygons without taking forever to load such data with the goal of allowing me to make each polygon ...
46
votes
5answers
36k views

What raster smoothing/generalization tools are available?

I have a DEM that I would like to smooth or generalize to remove topographic extremes (chop off peaks and fill-in valleys). Ideally, I would also like to have control over the radius or level of "...
27
votes
6answers
14k views

Maximum number of point features in an OpenLayers vector layer

In your experience, how many point features can be added to an OpenLayers vector layer (new OpenLayers.Layer.Vector("Point Layer")) before it goes unusably slow? My use case is to display points from ...
23
votes
5answers
2k views

Simplifying geometries (generalization)

What are the recommended ways of simplifying geometries? Keeping in mind projections, and simplifying state geometries for example. I've heard about converting to an 'equi-distant' projection that ...
22
votes
3answers
14k views

Seeking Generalisation Strategies for Building Outlines in PostGIS?

I have a dataset of building footprints vectorised from a raster dataset. The dataset is currently just a vector representation of the raster data. I would like a polygon dataset that only has ...
12
votes
5answers
7k views

GML, KML, GeoJSON - Speed rendering 3109 polygons?

I am working with Geoserver, serving U.S. Lower 48 counties to openlayers (3109 polygons - lots more vertices). The counties are loaded into a postgis database. I am curious about developer ...
7
votes
6answers
2k views

Tool/Algorithm for generalizing OSM-Files for printing maps

Is there a tool or algorithm to (topological) generalizes OSM-shapes? I would like to build a printable map in different scales. In the image below you can see the same divided road (yellow) at ...
4
votes
5answers
2k views

Simplify shapefile parcel layer

I have a very large shapefile with over a million parcels within it. The problem I am having is that the polygons representing each parcel are very jagged. What I am looking for is a simple and fast ...
12
votes
4answers
719 views

How to generalize coastlines?

I have a large set of data points that essentially represent the coastline of the world. I don't know the exact resolution but I'd say it's in the neighbourhood of 5-10m. Imagine a set of points ...
3
votes
2answers
1k views

How to speed up the process of vector data visualization for a web application

I have a GIS web application and vector data that is going from the model to the web application. For developing the User Interface I am using JavaScript and OpenLayers. But sometimes the amount of ...
2
votes
4answers
1k views

Openlayers Vector Rendering [duplicate]

I've just added a couple of more WFS backed vector layers to a map and the performance has dropped. Whilst debugging this I've noticed that openlayers is considering every feature in the visible ...
6
votes
1answer
557 views

GIS storage format for better performance - Android device

We have developed an android application which loads different eco-zones and does geo-fencing based on current GPS location. We have converted a shapefile to KML, then to JSON format, for loading in ...
1
vote
0answers
118 views

Resolve Building Conflicts - the open source way?

In ArcGIS there is a tool called Resolve Building Conflicts and I'd like to achieve the same using only open source tools (QGIS, GDAL etc), preferably on Mac OS instead. In the long run I'm trying to ...