[Qgis-developer] standardisation of the editing map tools: modify behaviour of press-pan-release tools

[Denis Rouzaud]

Hi Ramon,


On 24.09.2014 13:23, Ramon Andiñach wrote:
> On 24/09/2014, at 16:56 , Denis Rouzaud wrote:
>
>> Hi all,
>>
>> There is somehow an inconsistency in the behaviour of the current editing map tools.
>>
>> Some, like add features, uses the left click to trigger the action.
>> Others, like the node tool or move feature use press-pan-release mouse events:
>> * mouse press to select the node/feature
>> * mouse mouse to move it
>> * mouse release sets the position.
>>
>> I would propose to standardise this and for the latter tools propose the following work flow:
>> * left click enables the move
>> * left click again to validate at position
>> * or right click to cancel
>>
>> Why changing this?
>> If you look at CAD software, they also use the proposed approach. And there's a reason for doing so, which is valid for QGIS too.
> With all due respect I've never understood why click-click is better than click-drag for moving.
> I've always found select and drag far more intuitive and echoes equivalent actions in most of the other similar tools I use.
There is no overhead: still the same number of actions with the finder 
two presses instead of a press + a release. And you gain the freedom of 
your finger to do something else while moving.

I suspect, in such cases, we speak more from experience rather than true 
intuition. People with long CAD experience find the click-click much 
more intuitive than people used to dragging-and-dropping pictures into 
word the other way around.
>
> As for the apparent inconsistency, in my head they're different sorts of things.
> If I'm adding a feature, I put it (click) here.
> If I'm moving a feature, I pick it up (click-drag) move it to there and put it down (release).
>
> I further suspect that since the node tool does more than just move nodes, this is probably asking for a separation into node-move and a node-insert and a segment-move and a... tools.
> I really like having all of these in one tool, instead of perpetually going off to some menu to pick a different tool.
>
> [snip]
>> This is why, changing the map tools behaviour is requested if we want to go further with CAD tools in QGIS.
> Please say this isn't a case of; we need to change the established behaviour of the main program to make a plugin work better - because it's pretty easy to read that way.
That's a way of reading it. The other way is we need this if we want to 
go further with CAD tools in QGIS.
I could propose to go directly with CAD tools in core, but answers like 
yours prove we need to go step by step. Otherwise, it'll be impossible 
to reach a consensus. We need first some good plugin example to find the 
best way to go.

So yes, the idea is to make the plugin work better to later integrate it 
in core - whatever plugin that is.
Anyhow, any CAD tool will require this change.


Denis