[GIS] Source of Contour Lines for QGIS

contourdataelevationqgis

I am planning to go on multiple days hike and used Wikiloc to download GPX tracks. We will use a GPS for our navigation but I always want a printed map as a backup.

Maps for that area are notoriously bad but OpenStreetMap contains most of our trails and Points of Interest.

I loaded the track in QGIS with the OpenStreetMap and this is a good start. The only thing that is missing are contour lines (elevation lines) and potentially hill-shading.

What is the easiest way I could add contour lines and hill-shading to my map (for a printout)? Ideally, I would add a WMS or VectorTile layer and not go through the process of downloading a DEM and creating everything myself.

UPDATE:

It is fairly easy to add a mapbox WMTS layer to QGIS. I opted for the Outdoors mapbox style which has both contour lines, hillshading and OSM trails. However this introduced another problem. When printing / exporting the scale of the WMTS layer changes and becomes unreadable.

However when exporting using the print composer this is the result:

similar issue
another

Best Answer

Depending on your needs for precision you could use THE SRTM dataset. I found a nice tool, which allows you to download contour lines by selecting the area of interest in a map.

The website OpenDEM provides an easy to use tool to download the data.

Under downloads choose "SRTM as Contours"
Click on the web client and you will see a map as in image 1

With SHIFT + Left mouse draw and rectangle to select the datasets
Download the datasets from the popup window (Botten)
Open them in QGIS you will get your contour lines
Style them to your liking(add Labels as in image 2)
Optional: If you don't already use QuickMapServices, use it to get an OSM background map. I made the experience that the maps have better resolutions.

Disclaimer: I am not associated with the website

Related Solutions

[GIS] Interrupting contour lines beneath elevation labels (instead of using label buffers) using QGIS

Yes, doable. Normally I'd suggest a partially transparent buffer, but I see why you want to do this cartographically.

This could be slow, and you need to manually decide where you want the labels to go - but cartographically speaking, that's not a bad thing!

Here's a screenshot...

As you can see, no buffers. The raster underneath is unaffected. I've included thinner intermediate contour lines, and styled them so they're only shown when ELEV % 50 <>0

I've done this in QGIS 2.12 ... your mileage may vary with earlier versions.

I assume here you have an "ELEV" field on each contour line.

Segmentize the contour lines

Use processing and the GRASS algorithm v.split.length to split your contours into segments of equal length. You need to choose a length which will be close to the size of your label in map units, assuming you're using meters. Here I used 200m.

Be careful with this as it will make your file much, much larger (note the feature counts in the screenshot).

To get around this, you might want to generate only those contours lines you wish to style (e.g. every 50 or 100 meters) to avoid processing all the intermediate contour lines.
To this layer, add a 1 digit integer field called showLabel. Default to 0 or NULL.
Change the label to only show on a segment where this field is set to 1. Use this for the label text expression...
```
if ( "showlabel" is not null, "ELEV", "")
```
I think if(expression,true-value,false-value) is fairly new; if using an older version, you can use CASE-ELSE
Change the line style so the fixed length segments are all drawn, except those segments where the label is displayed. So use Rule-Based rendering with two rules
```
Rule 1: "showLabel" is null
Black, 0% transparent

Rule 2: "showLabel" is not null
Any colour, 100% transparent
```
Now, all contours will show by default, but no labels.

Manually edit segments where you want to show labels

Go into edit mode and manually select the segments where you want the contour values to display, and set the value of showLabel to 1 for the selected features. You can use Ctrl + select (on Ubuntu/Win, Cmd + Ctrl + Click / on Mac?) to multi-select segments to speed things up.

This should now 'clip' the contours where you want the labels to show, and the labels will show in the gaps.

In this case, my label settings were:

CRS: EPSG 27700 (Local UTM for UK, in meters)
Text size: 50 map units
Placement: Parallel, On Line

Hope that helps!

[GIS] Labeling contour lines in ArcMap

Labeling using the Contour Placement style

Required: ArcMap

Clean (good) Data

Maplex Labeling Enabled. (see http://resources.arcgis.com/en/help/main/10.1/index.html#/A_quick_tour_of_the_Labeling_toolbar/00s800000014000000/)

The Maplex Label Engine groups the segments of contour features, if the symbology and label match and the features are connected, and treats them as single, long features

enter image description here

Official Documentation on Contour Label Placement

http://resources.arcgis.com/en/help/main/10.1/index.html#//00s800000064000000

Best Answer

Related Solutions

[GIS] Interrupting contour lines beneath elevation labels (instead of using label buffers) using QGIS

[GIS] Labeling contour lines in ArcMap

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