# Questions tagged [buffer]

A region enclosing a point, line, or polygon at a specified distance.

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### how to buffer a line with varying distances associated with directional quadrant with open source GIS?

I would like to buffer a set of lines with different distances to the NW, SW, SE, and NE. I have the distances stored in four attribute fields that correspond to the direction the buffer should be ...
0answers
102 views

### Single Sided Buffer Error QGIS

I have delineated a shoreline and created an offset "buffer" of 75' and 250'. When projected onto the screen it appears as though a computation error has occurred and the buffers extend onto the left ...
0answers
71 views

### Creating Raster that sums up input polygons using QGIS?

I am using QGIS and I have a shapefile with buildings. From these buildings, I have built Buffer with variegating radius. The Buffer also have data about the demand for Parking spots for each building....
0answers
203 views

### Using transform function in QGIS layer geometry generator?

I'm trying to use the following expression in the geometry generator in a QGIS layer to show a 1-mi boundary around points: buffer(transform(\$geometry, 'EPSG:4326', 'EPSG:2877'), 5280) However, the ...
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159 views

### Drawing “proportional” buffer using QGIS or GRASS?

I'm working on aquatic vegetation and have a shapefile representing floating vegetation in a lake. By some studies, we know that submerged vegetation extends for a certain extension based on floating ...
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330 views

### How to Simulate Venn Diagram of Buffers using QGIS?

For the sake of simplicity, suppose I have only 2 points on one layer. Point A have population of 100, and point B have population of 150. I do find buffer of these 2 points and it is intersect. I ...
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1k views

### Buffering a Raster with GDAL and Numpy

I am using GDAL to convert a raster dataset into a numpy.array and then using numpy to buffer the data in the raster. For example, I need to know all the regions within 100ft of a school point ...
0answers
42 views

### What is the name of the popular buffer algorithm?

There is a well-known algorithm that I believe is used for the "buffer" function in some GIS libraries and applications. I have a vivid memory of reading the paper that describes the algorithm and ...
0answers
45 views

### How to use the output of one run as input to the next in QGIS batch processing?

I'm trying to do a series of buffers using the processing batch interface, and I want to use the output of the first run as the input to the second (and so on). But I can only pick an existing file or ...
0answers
94 views

### Expanding polygons and clipping at midpoint?

I have several separate shapefiles with polygon features. The end goal is to maintain separate shapefiles for each polygon but form a contiguous, non-overlapping coverage for my area. Basically, I ...
0answers
261 views

### How to apply a rectangular buffer on spatial polygons in R/qGIS

I am trying to find a way to apply a rectangular buffer on my spatial polygon dataframe in R. At the end, I would like to be able to shrink my polygons by specified units on both sides. So far, I have ...
0answers
77 views

### How do I report area statistics for land cover classes at equal sections along a river?

I have a river outlined: Using QGIS, the Semi-automatic Classification plugin and Landsat 8 images I classified the habitats (blue=water, yellow=sand/rock...,green=vegetation/algae) inside the river ...
0answers
255 views

### Displaying symbology outside map canvas window extent?

Say we have equally distributed x,y mesh vector file. Each coordinate has a map-unit based diameter circle symbology. If we zoom into a region of the map canvas far enough, some centroids exist ...
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341 views

### How to use buffer() in QGIS Value Relation field

When adding a point, I'd like to auto-populate one of its fields (the street address) setting it to a field in the nearest point in another layer (a layer containing all existing addresses). It ...
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43 views

### QGIS degrees - meters

I have point data in GDA2020. shapefile *.prj file says units are meters. when I load the data in QGIS the layer units are degrees nd the buffer tool is always degrees. I have searched for every ...
0answers
35 views

### Calculating variable buffers using slope between river and point 100' away using ArcGIS Pro?

I have a network of streams that I need to buffer based on a basic rule set. This buffer will depend on the slope. The slope is determined by the looking at the difference in elevation between a ...
1answer
104 views

### Subdividing square buffer in sub-units using QGIS?

I've been trying for a while now to create a grid inside a square buffer, so that it can be divided into a pre-defined number of sub-units. Creating a grid that covers the whole area is not ideal ...
0answers
41 views

### Searching on the fly within buffer in QGIS

I am using "Unique Values" widget with "Editable" option in QGIS 2.18.3, for my "Name" field in POIs layer to eliminate spellings mistake. "Unique Values" widget fetches all the distinct values in a ...
0answers
179 views

### RasterizeLayer in GDAL Java

As per the suggestions given by Michael to one of my earlier query (URL given below), I have tried to develop a sample code to perform rasterize using GDAL Java API methods. I had written based on ...
0answers
92 views

### Converting single point layer to buffered raster using QGIS?

I'm trying to use the proximity tool to create a distance raster from a single vector point. I found here: Calculating distance to points in QGIS and [d-3] Create Proximity Raster. However, I couldn't ...
0answers
106 views

### QGIS - Label Rectangle/Buffer Overlapping Layer Above

When I apply a buffer or rectangle to my labels they show through the overlying layers. Is there any way to avoid this, i.e. arrange the label so it lies underneath the layers above? I'm assuming the ...
0answers
50 views

### Achieving the opposite of the shortest_line() function in QGIS?

I currently use the Geometry Generator styling on a point layer to draw the intersection between protection buffers around tree points and another polygon (say a building footprint) using the ...
0answers
74 views

### “two ways” Reclass QGIS

I'm a forestry technician and I've one question dealing with forest road planning... in order to calculate areas that can be cover by a specific machine (with a given work distance) I do as follow: "...
0answers
152 views

### Is there an open source library that offers geodesic buffering of large polygons?

I need to buffer some large polygons and minimize distortion. Is there an open source library that offers negative and positive geodesic buffering of large polygons? I am aware ESRI has an ...
0answers
54 views

### wkid error using buffer GeometryService - ArcGIS JS API 3.2

First of all, going to this url for the geometry service referenced in the documentation shows it's been deactivated so I instead chose this url - both with /GeometryServer and /GeometryServer/buffer. ...
0answers
191 views

### Flat-ended buffers on touching polygon features in QGIS?

Please note that emphasis is on POLYGON here NOT POLYLINES! I need Buffer/s on one polygon, with two touching features and straight touching parts after difference has been applied I do not want ...
0answers
62 views

### Buffer function crashing QGIS only on specific data set

I'm trying to run the buffer tool on a line and it keeps crashing Qgis. The line is created by merging two sets of gps point data and running points to lines with gps_date as the order. I have no ...
0answers
410 views

### Fixed Distance Buffer not Buffering Features with Holes

QGIS 2.18.5 I've created a viewshed over a hilly area and I would like to add a fixed distance buffer just to compensate for any underestimations from the viewshed plugin's result. This is the ...
0answers
485 views

### GRASS v.buffer.column and v.buffer.distance - Incomplete Output

I have tried .column and .distance buffers within QGIS and both are leaving me with incomplete results. Only a few of the features within my input file are actually being buffered. I also have both "...
0answers
94 views

### Automatically split line at intersection of nearby shapes/zones

I have a large dataset in QGIS with roads (blue line in picture below) and 3 type of zones (mostly rectangular areas, red and green shape in picture below). My task is to spilt to road into segments ...
0answers
62 views

### Creating a cumulative factor based on multiple buffers

I'm using QGIS 2.12.0 and am trying to formulate a hierarchy for the risk factor associated with footpath polygons based on their proximity to pedestrian generators and the importance factor of that ...
0answers
2k views

### Extract values from Rasters in R based on spatial points and spatial polygons

I am trying to extract values from a raster file using the extract command in R mentioned here: http://www.inside-r.org/packages/cran/raster/docs/extract My raster file is unprojected (WGS84 ...
0answers
168 views

### How to create buffers having regard to topography with QGIS

I want to create buffers of 25 kilometers around points in a point-shapefile with QGIS. My problem is that I don't need an air-line distance of 25 km around the points, but a "real distance" having ...
0answers
216 views

### ST_Buffer with segment AND endcap parameters

Making a QGis plugin that buffers a line and I want to declare a high number of segments and a flat endcap. ST_Buffer(geom, 40, 25, 'endcap=flat') This doesn't work with both parameters entered, it ...
0answers
72 views

### Distribute Hotel Beds According to Population Density in Buffers using ArcGIS for Desktop?

I am running an ArcGIS for Desktop analysis where I am plotting competing hotel facilities and then distributing their beds in a 5-mile buffer around the site. I would like to distribute the beds ...
0answers
76 views

### Distribute population to health facilities (GP Practices)

I have been using GIS (ArcGis) for some years but I do not consider myself an expert. I am performing some analysis around GP Practices in London (UK), I would like to be able to estimate the ...
0answers
117 views

### Determining homogenous blocks of individual tree species in a woodland, and creating a new shapefile without blocks/polygons of < minimum area?

I'm working on a project attempting to identify suitable woodland habitat for red squirrel translocation wherein conservation efforts could be focused. Below is a small section of the map showing ...
0answers
308 views

### Large buffers in PostGIS (5000 km radius)

I have a number of points stored as geographies in PostGIS (version 2.0.1), and I'd like to create rather large buffers around them (with a radius of 5000+ km). However, ST_Buffer doesn't handle this ...
0answers
204 views

### How to spatial join points attributes to layer with two (or more) overlapping buffers in QGIS?

I'm working with QGIS 1.8 and I've got 3 layers : 2 points layers, and 1 layer composed of the buffers of one of the points layer. I'd like to retrieve the informations, for the point layer that isn'...
0answers
571 views

### Creating a Geodesic Polyline Buffer in OpenLayers

I have a feeling that the answer is going to be 'You can't do that without some very complex coding' but I thought I'd go for it anyway. I recently asked Creating Polyline Buffer in OpenLayers 2?, ...
1answer
721 views

### Variable buffer radius in ArcGIS JavaScript API?

I'm trying to combine the following Esri samples, to end up with the ability to create buffers based on a variable radius, that will then query data within the buffer zone. https://developers.arcgis....
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31 views

### How to clip polygon such that only regions in 'line of sight' from a point remain

I am using ArcGIS. My point represents a monitoring station and is located within a polygon representing a river catchment. I have created a buffer of 300m representing the detection range of the ...
0answers
42 views

### Measuring wrong, EPSG:27700 in QGIS3.6

If "enable on the fly" is on and the CRS changes at all during the lifetime of a project then seemingly, it refuses to measure (using the measure tool I just get 0.00000). So new project with all the ...
0answers
25 views

### Adding distance when buffering point geometry in a geodataframe?

I have 2 geodataframes that I want to combine. They the same fields/columns but different geometries (one is points, one is polygons).To do this I want to buffer the points slightly (like 10m or ...
0answers
21 views

### QGIS 3.6 QUICKOSM buildings query CRS with metre untis to create buffer

Using QGIS 3.6.2 I'm running a QUICKOSM query to find residential buildings in Scotland. I want to then put a buffer around them. The query is fine, if a little slow. The only CRS I can get to ...
0answers
41 views

### PostGIS - Get geofence polygon points within 100 metres of an existing geofence

Let's say I have a geofence polygon with the following coordinates POLYGON((-36.861986 174.726745,-36.859241 174.730442,-36.859821 174.730976,-36.862321 174.728156,-36.861986 174.726745)) I'd like ...
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21 views

### Creating buffer around points (layer + map in the same PCS)?

Currently creating a map of fire stations in LA and want to create a 50-mile buffer around them. My project right now is in NAD 27 / EPSG:26799 (Projected CS). I also managed to save my shapefile with ...
0answers
34 views

### QGIS Multi distance buffer units do not align with the main layer

I have a buildings shapefile of Beijing. I know the projection WGS_1984_UTM_Zone_50N WKID: 32650 Authority: EPSG So I would like to create multi distance buffer from a central point but when I do so, ...
0answers
71 views

### Fixed distance buffer is oval in QGIS?

I want to create circles of diameter 20m in QGIS. I create a point and then use vector - geoprocessing tools - fixed distance buffer. My problem is that the size is crazy and worse, the shape is not a ...
0answers
34 views

### QGIS3 difficulty drawing 150km distance buffer and showing this on the map

I wanted to construct a 150km distance buffer around a city in North America. I changed the project co-ordinate system of the point to WGS84 Mercator North America from WGS 84 Lat/long to enable the ...