[Qgis-user] Avoiding Label Clustering and custom placement

[Alister Hood]

Hi,

> Date: Tue, 25 Oct 2011 00:13:25 +0100
> From: Gerhardus Geldenhuis <gerhardus.geldenhuis at gmail.com>
> Subject: [Qgis-user] Avoiding Label Clustering and custom placement
> To: qgis-user at lists.osgeo.org
> Message-ID:
>
<CAATm_0rVMbzP0No72V4YtuWzJcO-cTije163Sqjd-th8D5uD3A at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> Hi
> I wanted to initially ask how do I avoid labels being on top of one
another
> if data points are very close to one another. I then had a look at
>
http://www.youtube.com/watch?v=sXK_0eEH3hc&feature=BFa&list=HL1319492137
&lf=mh_
> lolzwhich
> does to an extent have the answer I was looking for. It appears that
> there is not automatic way and that I have to manually do label
placement.

If you use the "new" labelling engine (the buttons on the toolbar) the
labels should automatically be positioned so that they do not overlap.
You should not need to use data-defined label placement to achieve this.
Perhaps you were previously using the "old" labelling engine which is
available as a tab in the layer properties?  The old labelling engine
does not avoid label collisions.

> However here is my problem, I have imported a set of points from a CSV
file
> using the "Add Delimited Text" layer plugin. Firstly I could not add
any
> custom columns that I could use to set my label x and y co-ordinates
again.
> So then I realized/thought that QGIS would probably not be writing
back to
> my CSV file, so it wont add additional columns. I then added my own
columns
> and set the values to 0 but when I set that my data defined positions
it
> does not work, my labels disappear. I have initialized the values to
be zero
> so perhaps that is the mistake... or perhaps qgis still can't or wont
write
> back to the CSV file.

QGIS opens CSV files read-only (well, there is a way to open them so
that you can add new entries, but not edit existing ones).

> So a number of questions:
> Is the CSV file only imported once or is it dynamic so will it thus
grow,
> shrink everytime there is a change to the file and I reload my
project?
> How can I add custom writeable attributes to a CSV imported layer, if
at
> all? Or do I need to "import" the CSV file and convert it to an QGIS
type
> format?
> Am I approaching this the correct way or is there an easier way to
customize
> my label setting so that I don't have labels overprinting.
> 
> Regards
> 
> --
> Gerhardus Geldenhuis

Alister