[GRASS-dev] wxGUI/vdigit: add centroid

Hi,

wxvdigit allows in trunk (r35872) and devbr6 (r35873) to add
automatically centroid to valid areas. You can set this functionality
in the settings - 'Attributes' -> 'Digitize new area'.

* add centroid to left/right area

When new boundary is added, left/right area is checked. In the case
that area is valid (closed) and has no centroid, new centroid is
added.

* do not attach category to boundary

When digitizing new boundary, category is attached only to the newly
added centroid.

Testing welcomed.

Martin

--
Martin Landa <landa.martin gmail.com> * http://gama.fsv.cvut.cz/~landa

On 14/02/09 14:44, Martin Landa wrote:

Hi,

wxvdigit allows in trunk (r35872) and devbr6 (r35873) to add
automatically centroid to valid areas. You can set this functionality
in the settings - 'Attributes' -> 'Digitize new area'.

* add centroid to left/right area

When new boundary is added, left/right area is checked. In the case
that area is valid (closed) and has no centroid, new centroid is
added.

* do not attach category to boundary

When digitizing new boundary, category is attached only to the newly
added centroid.

Testing welcomed.

Seems to work alright, although I do find this potentially dangereous as users might not really understand what they are doing... (but I am conscious of the fact that this functionality is what most people would expect...) At least, I think that "do not attach category to boundary" should be the default when "add centroid to left/right area" is set. Actually, I think it should always be the default and that if a user want categories for boundaries she should set it explicitely.

A few +/- related remarks:

- Could manual entry of category number be part of the pop-up window that shows up when you finish digitizing a feature. Having to go back into the paramters window for changing the category for every feature is very cumbersome.

- Trying to digitize a polygon which uses one boundary of another, existing polygon, I understand that I need to add new vertices to the existing polygon at the places where the new polygon boundaries touch the existing one. However, whatever I try, I cannot add new vertices. When I select the tool and click on a boundary I see a red cross at the place I clicked, but I cannot get it to stay.

Moritz

Replying to myself:

On 16/02/09 11:18, Moritz Lennert wrote:

On 14/02/09 14:44, Martin Landa wrote:

- Trying to digitize a polygon which uses one boundary of another, existing polygon, I understand that I need to add new vertices to the existing polygon at the places where the new polygon boundaries touch the existing one. However, whatever I try, I cannot add new vertices. When I select the tool and click on a boundary I see a red cross at the place I clicked, but I cannot get it to stay.

I forgot that I needed to "break the line" instead of adding a vertex. Still not sure I understand what "add a vertex" does, but that's not relevant to my question here.

Moritz