A type of cartographic generalization in which the important characteristics of features are determined and unwanted detail is eliminated to retain clarity on a map whose scale has been reduced.

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2
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1answer
513 views

Why are my polygons automatically simplified/generalised when merging them in ArcMap 10.2?

I am creating a small land use map, as an exercise for visual image interpretation. I created a shapefile and started digitising polyogons with the polygon tool. The problem is that some of my ...
2
votes
2answers
239 views

How to simplify streets such that seperate driving tracks are reduced?

Streets in Openstreetmap have more detail than I need. For instance I do not need seperate street tracks for each driving direction, instead I just want to show the general path of the street. Example:...
2
votes
0answers
134 views

Simplify by number of points in QGIS

I have a fairly simply question about something I just don't know how to do. I am aware you are able to simplify polygons in QGIS based on distance tolerance but my questions is, is there a way to ...
2
votes
0answers
619 views

Smooth, not simplify, lines features in PostGIS

I'm trying to automatically generate paths to place labels on that follow the shape of rivers, 4wd tracks and other very windy lines. At first I thought the st_simplify() function was the answer, but ...
1
vote
2answers
2k views

Removing unnecessary vertices?

I have over sampled polygons that I need to simplify, without changing the shape. basically, I want to reduce the number of vertices, by eliminating the ones that are useless and have the polygons ...
1
vote
1answer
84 views

Generalize lines with specific points

It's been a while since I was here. I have this problem now. I have electricity line feature class and point feature class intersecting line features. What I need to do is simplify this line feature ...
1
vote
2answers
90 views

Simplify geometries but keep them contiguous

I have several detailed contiguous areas. I need to turn each one into KML, but when I do so, the end result is too large (in terms of memory). Using PostGIS I need to simplify these geometries but ...
1
vote
2answers
154 views

simplify point geometry

I have a great amount of points and I need to show them on map. I am using OpenLayers. Is it possible to simplify point geometry in order to speed up the process of rendering?
1
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1answer
46 views

Can I simplify geometry on the fly in a ArcGIS JavaScript map viewer?

We've got a polygon feature class of parcels around a lake boundary that is incredibly accurate. The editor did a really thorough job of following all the inlets and meanders along the edge. From just ...
1
vote
2answers
58 views

Cannot Select 'Input line or polygon vector layer' when trying to simplify Shapefile

I'm trying to simplify a Shapefile by opening it in QGIS, Go to the Vector menu, selecting Geometry tools, and selecting Simplify Geometries... When I do this I get a modal window that I can fill out ...
1
vote
1answer
673 views

How Does Ogr2Ogr Simplify Work?

Can someone explain how the ogr2ogr simplify works? I am trying to use raster data which has a spectral resolution of 30m. The vector file that I am trying to import into Google Fusion is large in ...
1
vote
2answers
135 views

How to disable “Simplify geometry” via Python?

After I've loaded a layer from a table in my db I'd like to disable the 'Simplify geometry' (found in Layers/Properties/Rendering) programatically using Python. I've tried several versions of ...
1
vote
1answer
424 views

Algorithm to move polygon nodes when simplifying

I want to simplify polygons that come from a raster analysis. In order to avoid overlap and gaps, I first convert my polygons to lines. The problem is that all algorithm are then keeping the two end ...
1
vote
1answer
458 views

in QGIS, while using simplify feature, slider does not appear

Using Qgis both 1.8.0 and 1.7.4, the slider does not show up after selecting features and click "simplify feature" botton. Any special setting needed to show the slider? Thanks.
1
vote
0answers
38 views

Algorithm to simplify a Polygon/Series of Points to a given number of Points

I have a polygon (or let's call it just a series of points). I want to simplify it (reduce the amount of points) to a given number of points. Currently I use Douglas Peucker and try to guess the ...
1
vote
0answers
26 views

How can I use ST_Contains/ST_Overlaps with non-simple lines?

Following the SQL of the accepted answer to How to get smallest line segments from intersection + difference of multiple overlapping lines? copied below. I'm having some difficulties assign the ids of ...
1
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0answers
47 views

ogr2ogr (or other) simplification of polygons with shared boundaries

I am trying to simplify a collection of 100,000 or so polygons containing nearly 4 million vertices. The data is stored in a 2GB shapefile so there is no explicit representation of the topology ...
1
vote
0answers
54 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 ...
1
vote
0answers
91 views

Query to merge simplified polygons according to the map scale-factor

I'm trying to construct a view in PostgreSQL that simplify polygons according to the map scale-factor. Basically I was reading this thread http://linfiniti.com/2011/06/scale-dependent-generalization-...
1
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0answers
46 views

QGIS - Simplification process creates a new polygon - how to avoid it?

I am trying to simplify a layer made of polygons. I have used different methods but the new simplified layer has a polygon which intersect with itself, thus creating a "new" polygon. Please see ...
1
vote
1answer
92 views

simplify tiled geometries while preserving anything on the edge

I have a dataset of polygons split into evenly sized tiles. How can I go about simplifying them, but not along the tile edges, so that there aren't any gaps between continuous features when the tiles ...
1
vote
1answer
136 views

Reduce number of points, keeping most recent data within a given distance

I have a HUGE dataset of points that were collected along a route. The data may change daily, and the most recent data is the most important. What I would like to do is take only 1 point from a given ...
1
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0answers
34 views

Keep synchronization when simplify features from different data source

We have two shapfile data source: 1 water-riverbank.shp With geometry type of Polygon which stands for the area of water 2water-riverline.shp. With geometry type of LineString which stands for ...
1
vote
0answers
409 views

How to import large features to Google Fusion Table from KML?

I am trying to import rather large features to Google Fusion Table from KML files (I have also shapefiles). However, Google has a certain limitation: "a cell of data in Fusion Tables supports a ...
1
vote
1answer
199 views

Why won't lines from GPX simplify/generalize/smooth?

I am working with GPX data. I imported them to ArcGIS by 'GPX to feature' and then I created lines from these points. I am trying to smooth (or simplify) the lines now, but the tools 'smooth line' and ...
0
votes
2answers
107 views

Simplifying Ways in OpenStreetMap Data

Is there a (current) best practice to simplify ways? I have found: https://github.com/podolsir/osmosis-simplifyways But besides not being alive, here (http://permalink.gmane.org/gmane.comp.gis....
0
votes
1answer
172 views

Simplify polyline with the intersection point kept

I have a some line and polygon features which consist of too many points, so I tried to simplify them. I found the "Ramer–Douglas–Peucker algorithm". I think it will work well for a single feature (...
0
votes
1answer
143 views

What is the best way to get simplified UK boundary data?

I have some recent data that is at the Lower Super Output Area (LSOA) level for Greater Manchester. I wrongly assumed that the data was for the latest LSOA boundaries, i.e. for the 2011 boundaries. ...
0
votes
1answer
116 views

Simplifying polygons in ArcGIS considering contains-one-point topology rule?

I want to simplify polygons using the "Simplify Polygon (Cartography)" tool in ArcGIS 10.2. Additionaly there is one point in each polygon and this condition should still be fulfilled after ...
0
votes
0answers
37 views

Gdal ogr simplify/intersects

Can anyone give an example: How to use the simplification? For example // read the coordinates of the polygon char * wgsRef = NULL; OGRPolygon *poPol = (OGRPolygon *)...
0
votes
0answers
26 views

How to calculate tolerance for TopologyPreservingSimplifier in JTS?

I am trying to simplify some areal geometries (POLYGON\MULTIPOLYGON) using JTS's TopologyPreservingSimplifier.simplify(Geometry geom, double distanceTolerance) From the JavaDoc: void ...
0
votes
0answers
25 views

Can GeoServer be asked to clip a WFS response?

I'm fairly new to GIS, so I'm not very familiar with all the terminology and standards. What I need is a webservice that returns geographical polygons (countries and administrative regions) as GeoJSON....
0
votes
1answer
76 views

ArcGIS Raster To Multipoint Mac/OSX alternative

Is there an alternative to the ArcGIS Raster To Multipoint tool for Macs? The VIP thinning method is particularly of use. A comparative point cloud thinning/simplification tool to this would just as ...
0
votes
0answers
91 views

Reducing point numbers in a certain area

We have a list of poi data in our database(Access mdb db), and we have a web service which serve data by a specified BoundingBox. However we found that the returned points are too close to another at ...
0
votes
1answer
98 views

Simplify table of linestrings

I have a PostGIS table of linestrings representing a road network. I want to simplify the geometries such that only lines that connect road junctions are stored. At the moment the table has a large ...
0
votes
0answers
157 views

Can I simplify polygons in QGIS by Size?

Just wondering if it's possible in QGIS to simplify polygons based on size? I've done it many times using the tolerance level to reduce the overall size however in this case each polygon cannot be ...
-2
votes
1answer
196 views

How can I find a Douglas-Peucker algorithm for simplification? [duplicate]

I want to understand simplification methods in GIS. I searched the Internet and found that the best simplification method is the Douglas-Peucker algorithm. I could not find any information about the ...
-3
votes
1answer
60 views

Simplify shape files [closed]

I've shape files with me and I want to de-code those file and want to build a custom map. Could someone let me know how can I do that with out using python code.