[Qgis-developer] Unique value renderer in New Symbology?

[Martin Dobias]

On Fri, Nov 18, 2011 at 5:02 AM, Giovanni Manghi
<giovanni.manghi at gmail.com> wrote:
> Hi Gary
>
>
>
>
>> 2. Will there be a unique value renderer in new symbology?
>
>
> I agree, using the categorized symbology with a random color ramp
> produces not good results (many times with adjacent polygons with the
> same color), with ugly colors and is not straightforward to
> use/understand as the unique value renderer.

The assignment of colors for adjacent polygons is not addressed in
neither old nor in new symbology.

Ugly colors? The colors depend on the type of random color ramp you
use - a color ramp having colors with higher saturation will look
better.

Maybe the only issue is the usability - you need more steps to produce
an equivalent of unique value renderer. That may be addressed, some
ideas how to do it would be welcome.


>> 1. When will old symbology be removed?
>>
> I hope not before all the features that are available in the old one are
> ported in the new one. I also give many training courses and what people
> is mainly missing are:

Some time ago we started a wiki page which was supposed to list what
features were present in old symbology and not present in new
symbology:
http://www.qgis.org/wiki/Switching_from_Old_to_New_Symbology_and_Labeling
Unfortunately it turned out very quickly to a wishlist. I would
suggest cleaning all wishes and completing missing functionality.


> *) the overall transparency slider for all the renderers other then the
> unique value. Actually in master you can select multiple
> classes/categories, right click and choose the transparency (that by the
> way is defined with a 0.0-1-0 interval, where the slider is 0-100%) but
> again is not very handy (when having many classes) and not very
> intuitive

You may add that as a feature request...

> *) in the old selecting multiple symbology classes allowed the user to
> change the symbol for all that classes in one go. In the new symbology
> you can select multiple classes but, if the button "change" is click
> then the symbol options are applied only to one of the classes

Umm... the original idea was that the button "change" is just for
changing the _source_ symbol, not actual selected symbol(s) in the
list. This seems to be quite misleading to people and we should do
something with it... I refer to the whole thing about selecting source
column/ramp/symbol - we discussed it on the list with Marco recently.

Maybe a better approach would be:
1. when categorized/graduated renderer is first selected in combo box,
it will only show the widgets needed to do classification
2. after classifying those widgets would be hidden (or minimized), not
to confuse people, while allowing more space for the list at the same
time


Martin