[Qgis-user] Enhanced labels in 1.7.0

[Andrew Chapman]

Thanks for the feedback Andreas. I'll try just to use the "ABC" tool from
now on - I realise that it is still in development, so my comments aren't
criticism, just trying to understand how the tool is intended to work and
where its development is at the moment.
So for a point shapefile, starting with "Label this layer" checked and an
appropriate attribute selected for "Field with labels", no buffering and "In
map units" selected, I then get text displayed as I would expect. I can
change font, colour and size. However, when I start to experiment further,
things get a little more complicated. If I set the size to zero (limit case
test) and then "Apply", there are no complaints about the value but the
on-screen text doesn't change. If I exit the dialog and return, the last
accepted value has returned, so this would seem to be a very minor bug.
Playing around the limit, I found that 0.0001 map units works ok, so for my
metric CRS this equates to a text height of 0.1 mm - I could even zoom in
from the whole world to labels on individual PCB tracks in my PC at that!
The next step was using "Data defined settings" with a more realistic range
of sizes defined by attribute and the placement set as "over point". This
generally worked as expected, except that the "Label settings->Size" value
changes the vertical placement of the label, in my case by approximately 0.2
* value - I had expected this control to do nothing in these circumstances.
As an aside, I didn't really understand most of the settings on the
"Advanced" tab, including the difference between "around point" and "over
point".
I tried the "Data defined. color" and it worked with the described #rrggbb
where rr, gg, bb are two hex digits for colour. However, before getting your
response I tried the simple text string "red". and got red text! It would
seem that there are also some pre-defined (English only?) colours.
Bold, italic, underline and strikeout all work as boolean values with Null
and zero equating to False and (as far a I can see) any other value equating
to True.
Font family works ok with any recognised font family name. Any values that
aren't recognised are ignored and the font family defined on the "Label
settings" tab is used instead.
To get buffering to work, it appears that "Buffer" has to be checked on the
"Label settings" tab to get either normal or data defined buffering. The
buffer size is shown in mm, although this doesn't relate to the map units
used (metres in my case). As I zoom in and out, my labels (in map units)
scale, but the buffer remains constant.
Buffer colour uses the same format as font colour.
I didn't try label distance and X & Y coordinates.
Horizontal and vertical alignments are currently inactive.
Rotation similarly is inactive. Unless I'm missing something, the only way
that I can use the rotation attribute in my data is to go back to the old
style.

Andrew