[OpenLayers-Dev] editing controls, preserve selection

[Steven M. Ottens]

On Aug 23, 2007, at 12:56 PM, Pierre GIRAUD wrote:

> Comments below.
>
> On 8/23/07, Tim Schaub <tschaub at openplans.org> wrote:
>> Steven M. Ottens wrote:
>>> Hi Pierre,
>>>
>>> I'm currently more involved in user interaction design and not so
>>> much in coding so it could be that I'm cutting corners which are  
>>> hard
>>> to cut but:
>>>
>>> why do you need to switch between modifyFeature control and
>>> deleteVertex control?
>>>
>>
<snip>
>> Next, we need delete vertex and add vertex controls.  Alone, these  
>> would
>> do just what they say.  These could be aggregated with a modify  
>> feature
>> control (and even a draw feature control if you like) into a single
>> feature editing control that lets you drag around verticies, add new
>> ones, and delete existing ones. Combined with a draw feature control,
>> this would give you one control to draw and edit.
>>
>> Of course, there will be a lot of room for help from interaction
>> designers.  Ideally, we'll be able to use a combination of  
>> keyboard and
>> mouse input to activate and deactivate specific functionality in  
>> these
>> controls.
>>
>> So, perhaps you were suggesting the same - but I wanted to make sure
>> that it was clear that it *doesn't* make sense to develop the
>> full-featured editing control before having the individual pieces in
>> place.

Like I said I was cutting corners, obviously it makes sense to first  
develop the pieces before finishing the puzzle. I was already looking  
at the puzzle ;)


>
> I'm okay with that.
> In the camptocamp/feature sandbox modify-feature's example, we can add
> a vertex by moving a virtual point. This way I think we don't need an
> individual addVertex control. I might be wrong.
> On the other hand, I agree that the deleteVertex needs to be
> redesigned to become an individual piece.
>
I like the virtual vertices to add new vertices.
Having a separate deleteVertex control makes sense as long as it is  
possible to combine it with the modifyFeature to a single tool as Tim  
said above.

> About the problem of selection preservation, I pushed my reflexions  
> further.
> First of all, the unselect was called in the full featured controls. I
> just have to comment some code to keep the features selected when I
> switch between tools. My problem now is that I probably don't want to
> preserve the selection when I use a drawFeature control.
> I had a look at some vector editing desktop software. Inkscape is a
> good reference IMO and switching between different tools, the
> selection is kept until user starts drawing a new geometry.
> So, I now think that the drawFeature control could have an optional
> selectControl that selects the drawn feature and unselects in the same
> way the previous selected one.
>
> What is your opinion about that ?
>
It makes sense, if you start drawing a new feature there's no need to  
keep the old one selected. Even more it is confusing to edit one  
feature while another one is selected. People will probably think it  
as a (rendering) bug.

Steven
> Pierre