How to Force the Showing of Labels of a Vector File in QGIS

Question

I imported some OSM data. I then label the lines (roads) with their "name" field using the new label layering settings dialog box. When I zoom to different scale levels I find that while all the lines remain, some of the labels appear / disappear. In any particular zoom level if I adjust the size of the text of the labels, more or less labels show (i.e. when I make the text larger less labels show and when I make the text smaller more labels show). While in general this is good because it creates less clutter and keeps labels from overlapping, etc. there are times when I want to see some of these labels and I can't unless I adjust the text size or zoom in further. I also can't find any control over this either.

So, I guess I am wondering if there is a way to force all the labels to show no matter what my text size or scale is. Another option would be a way to turn on a particular label that I wanted. In fact the latter option would be best.

Thanks in advance for any help with this. David

Answer 1

An updated way to do this (at least in 2.6.0 Brighton) is to:

Go to Layer Properties>Labels>Rendering and check the box that says "Show all labels for this layer (including colliding labels)"

Answer 2

Using QGIS 1.8 Lisboa, you can make all labels appear all of the time. In the labelling dialog (from the button on the toolbar) there is an advanced tab, scroll down to Engine Settings and turn on Label All Even If Collisions.

The above is useful if you are going to position by hand some or all of the labels.

To position labels by hand, you need to have fields in the attribute table for x-label and y-label, the simplest way is to set them as Float fields with 10 units and 10 precision. Then you can activite the label positioning buttons on the toolbar and position labels as you please.

The more likely scenario is that you want to control visibility by zoom level. The settings for that are there as well.

For all of this, choose what zoom level (extent of map) you want to output to first, then do the work. A scale of 100 000 with about 300 labels at A3 at a font of 6 pts is just doable if they are equally distributed.