Questions tagged [simplify]
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.
181 questions
0 votes
3 answers
87 views
Simplify geometry originated from viewshed raster image
I am doing a viewshed analysis on a DEM .tiff file. I would like to convert the viewshed raster into vector geometry in the format of .geojson, which i have achieved, although, the result is not good. ...
- 113
-1 votes
1 answer
67 views
Polygon simplification [closed]
How do I simplify complex polygons in order to get simpler detailed polygons like this : ... keeping their topology
0 votes
0 answers
35 views
How to simpify a geodataframe geometries and preserve the contact between the polygons [duplicate]
I'm working with a map of the world from GADM dataset stored as JSON. The precision of the map is way too small for serving a web application so I would like to simplify it to 0.01° and thus reduce ...
- 3,460
1 vote
0 answers
87 views
How to ensure GRASS "v.generalize" simplifies all coastlines consistently?
I am trying in QGIS to simplify the geometries of the world's country borders (from here for example) to achieve a clean, generalized map display. To do this, I am using the v.generalize tool provided ...
- 141
-2 votes
1 answer
214 views
Simplify by removing overlapping lineparts in adjacent polygon features
I am looking for a way of simplifying my GeoJSON file by removing overlapping lineparts between adjacent polygons. I have a GeoJSON file with polygons of cadastral parcels which, by definition, are ...
0 votes
1 answer
369 views
Simplifying adjacent polygons with Python while maintaining shared borders [duplicate]
I want to simplify adjacent polygons (GADM zones level 1) with Python while maintaining shared borders. The general problem is well explained at Simplifying Polygonal Coverages with JTS. The best ...
- 17
0 votes
1 answer
344 views
Simplify multipolygon in Google Earth Engine
I am working on Google Earth Engine and trying to simplify a multipolygon by first reducing its vertices and then removing unnecessary polygons that have fewer than 5 vertices. var gaul = ee....
0 votes
0 answers
40 views
Transform the detailed vector layer in screenshot 1 into the simpler layer of screenshot 2
I have created a "detailed" vector layer of buildings from OS's VectorMap District data, styled with deprivation data (much like screenshot 1). I would like to create a simplified layer from ...
0 votes
1 answer
182 views
Simplify my vector data to display it more efficiently [closed]
I have >1Billions points data (in geoparquet but could gpck) that I have to display in QGIS in a scale that doesn't need such precision (=we will not see all the details). It takes age to load in ...
- 43
0 votes
1 answer
127 views
QGIS Simplifying polygons with keeping points inside of them
I'm creating a processing where I do calculations on address points inside of counties. I need to generalise county polygons in order to make my processing faster. How do I make sure that address ...
- 11
2 votes
0 answers
123 views
Seeking algorithm for polygon straightening
I have a polygon that looks like this: I want to get a result that ideally looks like this: The best that I can come up with is a polygon simplification using shapely in Python: Which algorithm ...
3 votes
3 answers
704 views
Why simplify algorithm has no effect on input in QGIS?
I have a LineString layer that I need to reduce the number of vertices. For example, some straight lines have intermediate vertices that add no value and should be removed. A slight loss of accuracy, ...
1 vote
1 answer
861 views
What are strategies to simplify a vectorized raster layer?
For a GIS web viewer I am building, I plan to use large sets of vector data on coral reefs (source: Allen Coral Atlas). When viewing the downloaded data, it seems that the original source was raster ...
- 800
1 vote
0 answers
159 views
Speed up intersection on large polygons with PyQGIS?
Is there a way to speed up my script? I am new to PyQGIS. I am using QGIS 3.16. What I need: I have 50 polygons (up to 1.675.000 hectares, mean 420.000 ha; one shapefile per polygon) and for each of ...
- 59
1 vote
0 answers
50 views
Invisible layers when splitting vectors after simplifying in QGIS
I am working with elevation curves and I want to group curves by elevation. I can do it with the Split Vector Layer tool (Vector, Data management Tools) and choose ELEV as a unique ID field. However, ...
- 11