[Qgis-developer] Postgis provider, add and modify linestring

[Andreas Neumann]

 Hi Denis

 On Mon, 23 Jan 2012 14:47:49 +0100, Denis Rouzaud wrote:
> Hi all,
>
> I observed a few changes I see as drawbacks.
>
> 1. When you draw a line, when you right-click to finish the feature,
> the current point is used. I think it is more consistent to place
> points with left-clicks and finish with a right, without adding
> anymore point.

 I think that this behaviour is not new but was always like this. This 
 is also a general digitizing issue and has nothing to do with the 
 Postgis provider, as far as I know. Personally, I am not sure what is 
 easier/best to finish digitizing a line.

 I had a look at other graphic software:

 * Inkscape: finish line with double click or right click, but right 
 click does not add a new point. This seems to be in line with what you 
 propose above.
 * Autocad: finish a polyline with enter key
 * Openoffice: finish a line with a double click - right-click undoes 
 last vertex.
 * Scribus: finish line with right click, but right click does not add a 
 new point. In line with Denis' proposal.

 In general I think that QGIS current solution with finishing a line 
 with right-click (while adding a new vertex) is not so bad, once you are 
 used to it. It means fewer mouse-clicks, which is nice. It might be a 
 little unfamiliar for new QGIS users, but I think people can get used to 
 it quickly - am I wrong?

 One issue we have with right-click and with double click is that it is 
 hard to replicate on a touchpad. Marco Bernasocchi, the current QGIS on 
 Android maintainer has to find a workaround because there are no 
 right-clicks on a touchpad.

 Any idea about a better way to finish digitizing a line?

> 2. Also, when I finish a feature, I have to commit changes and to
> refresh the canvas before I can see it on the map. If I am right, it
> did not used to be like this.

 That's strange - I cannot observe this behavior. It works fine on my 
 machine.

> 3. There is no add/remove node for a linestring. I am going to write
> this as a plugin. I this planned to be done? Did I look too quickly
> and this feature does exist?

 yes - this functionality is missing - and I think it should go into the 
 core (not just as a plugin). The functionality to extend a line is a 
 core functionality that everyone needs at some point.

 Andreas

 --
 Andreas Neumann
 Böschacherstrasse 10A
 8624 Grüt (Gossau ZH)
 Switzerland