26 votes

Drawing wavy/wiggly lines in QGIS

Short answer: you can get it using a custom SVG. See bottom of this post for one. Long answer: I believe it is better to represent it than to modify the line geometry. Should you want to move an ...
  • 37.8k
25 votes

Displaying overlapping points in QGIS

Try renderers: "Point displacement" or "Point Cluster" from symbology menu. (QGIS 3.x required for point cluster.) As point displacement they can look like this for example: And ...
  • 30.3k
22 votes
Accepted

Drawing wavy/wiggly lines in QGIS

I propose a solution using PyQGIS. It should work both for Linestring and MultiLineString layers. This solution is based on the creation of semicircular rings, so you need to set a value for the ...
  • 15.9k
20 votes
Accepted

Styling polygon layer as dissolved with QGIS Geometry generator

You can now do this with the geometry generator in QGIS 2.99/3.0 by using buffer(collect($geometry), 0) in the expression builder. The new collect() aggregate function collects all the feature ...
  • 8,784
20 votes
Accepted

Showing the bounding box for every coordinate system in QGIS

Yes, QGIS holds this information in an SQLite table. Go the menu layer / data source manager and select Browser then go to where QGIS is installed (like C:\Program Files\QGIS 3.16\) and dig down to ...
  • 37.8k
19 votes

Shifting display of overlapping lines in QGIS?

I propose an approach that only recurs to a geometry generator and a custom function. Before starting, I want to underline that I will focus the attention on the explanation of the minimal things to ...
  • 15.9k
17 votes

Viewing LIDAR data (.las) in QGIS?

QGIS 3.18+ supports point cloud visualisation natively.
  • 1,260
16 votes

Making lines curvy in QGIS

Use Arrows style instead of Simple Line style. For example, these lines with Simple Line style: look like this with Arrow style: You can turn off the arrow heads by setting the head width and ...
  • 23.8k
14 votes

Styling polygon layer as dissolved with QGIS Geometry generator

I've tried using the Geometry Generator with no success, and decided on a "Virtual layer" and a SQL query SELECT st_union(geometry) FROM layer_name You need to replace "layer_name"...
13 votes

Visualising WKT geometry string in QGIS

No Plugin required In QGIS deploy a "Virtual Layer" through Layer > Add Layer > Add/Edit Virtual Layer.... In the Query window simply paste the following expression: SELECT ...
  • 28k
12 votes

Setting layer visibility in QGIS Python API?

For QGIS 3, you have to use: QgsProject.instance().layerTreeRoot().findLayer(layer_id).setItemVisibilityChecked(False) or to be safe node = QgsProject.instance().layerTreeRoot().findLayer(layer_id)...
12 votes

Drawing wavy/wiggly lines in QGIS

Attention! This answer is outdated. Please follow the link here: Custom QGIS linestyle expression function won't work with MultiLineStrings In QGIS 3.10 it's possible to dynamically create zig-...
  • 4,636
12 votes
Accepted

Rule-based symbology in QGIS

On the symbology tab of the properties - Select Rule-based For the filter enter "riparian Veg" = 'Yes' AND NOT "Primary" = 'Riparian vegetation management' capitalization matters - it has to match ...
  • 5,781
12 votes
Accepted

Making an animation of an evolving digital elevation model

Probably the best tool for this is Paraview. Once you've downloaded and acquired that you'll want to load your images: Use the CSV reader to load them: Below, you can find filters faster by pressing ...
  • 1,801
12 votes

Filtering which points to display using expressions in QGIS

Use either "Drilled ID" in ('value1','value4','value8') Or "Drilled ID" = 'value1' or "Drilled ID" = 'value4' or "Drilled ID" = 'value8'
  • 30.3k
11 votes

Showing antenna symbols on the map: point symbols or features (polygons)

If you want to use symbology only, I propose a solution inspired by my answer from a similar question: Creating sector lights in QGIS?. Following a similar approach, and assuming you are working on a ...
  • 15.9k
11 votes

Changing marker shape based on a rule or column value in QGIS?

Assuming to start from a point layer having this Attribute Table: you can perform the third step: "Shape of marker denotes if the soil samples were taken in "topsoil" or "other"." by firstly ...
  • 15.9k
11 votes

Producing Space-Time Cube in QGIS

One option to do this would be by modifying your data and visualizing it with the excellent qgis2threejs plugin. The idea is to turn your your time to Z coordinates. I tried it out with two GPX tracks ...
  • 603
11 votes
Accepted

Setting constant labels positions in QGIS

In Labels tab in Layer Styling (F7), open the Placement tab. Click the Settings button below Label Anchoring. Select Use Entire Line for Clipping and Strict for Placement Behavior.
11 votes
Accepted

Filtering which points to display using expressions in QGIS

Switch to Rule-based and use "Drilled ID" IN ('value1', 'value4','value8') Consider setting a filter if you don't want to display anything else.
  • 60.7k
11 votes

Using multiple XY fields for geometry definition in point layer in QGIS

Use a Geometry Generator style for your point layer with an expression that creates a point based on x/y coordinate values for surveyed locations if it exists and else create a point based on x/y ...
  • 54.7k
10 votes
Accepted

Permanently viewing vertex of polygons in QGIS

Using the green plus in the symbology tab of your layer properties, add a second symbology. Change that type to border - marker line and the placement of the markers to every vertex.
  • 14.6k
10 votes
Accepted

Performing basic labelling with PyQGIS

There is no problem with @Kezah's answer. I've edited the script and it works. Please check it. Avoid using startEditing() and dataProvider().addFeatures() together. Use either one. If you construct a ...
10 votes
Accepted

Representing five categories of data in one symbol using QGIS

Using "Data defined override > Edit...", use the following expressions. (Edit field names) For "Size": CASE WHEN "Light"='Dark' THEN 4 WHEN "Light"='...
9 votes

Visualising WKT geometry string in QGIS

In QGIS 3.18.3 (Windows) we can copy one or multiple WKT strings into clipboard and past them using Edit > Paste Feature As > Temporary Scratch Layer... into map canvas. CRS needs to be adjusted ...
  • 4,636
9 votes
Accepted

Plot tilted map in R

The examples in your link look like the coordinates have been transformed via a shear and a scale matrix. You can easily apply this to the coordinates you get from the usual fortify/join data that ...
  • 58k
9 votes

Assign a specific color to vector layer based on RGB codes in attribute table

In the layer styles panel if you click on simple marker, there is a small box to the right of the fill color combo box - if you click on it you can select edit from the menu and enter the expression ...
  • 78k
8 votes

Viewing LIDAR data (.las) in QGIS?

Update: As stated in Peter's answer: QGIS 3.18+ supports point cloud visualisation natively. Some documentation for reference: QGIS 3.18 changelog. Installation guide. The crowdfunding initiative. ...
  • 10.1k
8 votes
Accepted

Visualizing large datasets of polygons with Leaflet

Firstly, check out this post. It may not be exactly what you want though, which is why I did not mark this thread for closure as a duplicate. Secondly, there are a number of tactics you can employ ...
  • 33.4k
8 votes
Accepted

How to assign colors to specific raster values using R

You can define your own color palette by concatenating two predefined color palettes and your desired gray color as: [red orange yellow palette] + [zero gray color] + [blues palette]. To get zero ...
  • 3,106

Only top scored, non community-wiki answers of a minimum length are eligible