Feature: Search for dynamic object properties

[dl3sdo]

Search for dynamic object properties (also mentioned in #2211), e.g.,:

• object violates minimum area or line length constraints
• object area size / object line length
• object creation and modification dates

This is a WIP, current state:

• calculation of object area size / object line length and constraint violation checks moved from measure widget to object base class
• 'Delete & Find next' functionality added to 'Find objects' dialog
• search for objects violating minimum area or line length constraints

Please have a look on the demo where I 'misuse' the minimum line length to search and delete small contour line artifacts (since not having implemented a real comparison of object area size / object line length yet)

DeleteFindNext.mp4

I personally like the 'Delete & Find next' functionality to easily check an object before deleting it when stepping through the found objects.
What do you think of this functionality, do you want to have it in Mapper?

[krticka]

This function is great enhancement! Few notes:

• because screen is not centered to new object with every find next click, it can be difficult to identify feature on the screen. I propose to add flashing of feature. For example frame around feature can have distinct glow and flash three times quickly
• I expect that for areas you will use AreaTooSmall, but other attributes to query would be beneficial. For example to query $geometry type and also to have option to handle/select objects without symbol which can come from OCAD and it is not easy to fix it efficiently in Mapper.
• friendliness of use - I would love to see intelligent query menu 1) you will define WHERE, you can enter symbol number but dropdown list with symbols including names will be also available, 2) you will define OPERATOR (is equal to, is greater than,...), 3) you will define VALUE(s) and another clause with AND/OR can be used
• future - I can imagine future application in enhanced legibility check which checks distances between objects of the same color. For example you can query $color and buffer distance to identify vertices which are too close.

[dl3sdo]

Hello @krticka,
thank you for your feedback and your proposals:

• I agree, I find it difficult as well. I have not found a Mapper function to center the screen to a selected object. Improving the usability is on my list.
• You are right ;-) AreaTooSmall is exactly the keyword. I added a new keyword UndefinedSymbol to search for objects without symbol. I did not extend the SYMBOL keyword to something like SYMBOL UNDEFINED due to the special implementation by Mapper (the specified symbol number is changed to an internal symbol address, something that could be handled differently, but that decision is up to Kai).
  Can you explain what you mean with $geometry type ?
• Indeed, there is room for improvements.
• I agree that is an important feature and I will think about how to implement it.

Do you have other proposals for checks?

Once the dynamic object properties feature exists, it's not so difficult to extend it, e.g., that's the code for searching objects with undefined symbols:

if (property == literal::UndefinedSymbol)
{
	if (map && symbol)
		return QVariant(map->findSymbolIndex(symbol) < 0);
}
return QVariant();

[krticka]

Hello @dl3sdo ,
with $geometry type my intention was to select all objects according to their geometry type (point, line, polygon) for some specific topological checks, but I have to think this all through. So please don't waste your valuable time on this.

AreaTooSmall / LineTooShort As I understand this this keywords will provide automatic checks against min. area/length defined in symbol menu. Will be there option to query specific value/length? Is there any list of implemented internal keywords available?

[dg0yt]

Is there any list of implemented internal keywords available?

The current state of the query language is docmented:
https://www.openorienteering.org/mapper-manual/pages/find_objects.html#advanced-query-language

Whatever is added should fit well into what exists at the moment. It might be possible to adopt SQL (and existing geospatial extensions). However, we are only dealing with the WHERE part of SQL statements here.

[krticka]

Thank you @dg0yt for sharing the link. This part of the help is known to me. The question to "internal keywords" is mostly driven by the question "What everything I can query?" For example if I select the contour and go to View/Tag Editor I will get empty result. Here I would expect to see at least keys TYPE, SYMBOL from object tag. Also, I would like to query objects which are using specific color.

On the other hand, the file is sometimes storing redundant information and it would be good to have an option to manage content stored in tags in some efficient way (at least deletion). For example for my latest sprint map I have imported from cadastral system shapefile with buildings via Template/Edit/Import and remove and now the file is polluted with information I will never use.

<tags><t k="fid">109</t><t k="gml_id">SO.14167794</t><t k="Kod">14167794</t><t k="CisloDomov">(4:130,132,133,305)</t><t k="Identifika">1482375809</t><t k="TypStavebn">1</t><t k="ZpusobVyuz">6</t><t k="CastObceKo">414603</t><t k="PlatiOd">2023-12-21T00:00:00</t><t k="IdTransakc">5292491</t><t k="GlobalniId">3266193</t><t k="IsknBudova">227997809</t><t k="Dokonceni">1980-12-31T00:00:00</t><t k="DruhKonstr">4</t><t k="PocetBytu">38</t><t k="PocetPodla">5</t><t k="PripojeniK">1</t><t k="PripojeniP">1</t><t k="PripojeniV">1</t><t k="VybaveniVy">2</t><t k="ZastavenaP">748</t><t k="ZpusobVyta">2</t><t k="DetailniTE">(4:23967,23968,23974,66673)</t><t k="Detailni_1">(4:2023-12-21T00:00:00,2023-12-21T00:00:00,2023-12-21T00:00:00,2023-12-21T00:00:00)</t><t k="Detailni_2">(4:3266193,3266193,3266193,3266193)</t><t k="Detailni_3">(4:4,4,4,4)</t><t k="Detailni_4">(4:11,11,8,8)</t><t k="Detailni_5">(4:5,5,5,5)</t><t k="Detailni_6">(4:1,1,1,1)</t><t k="Detailni_7">(4:1,1,1,1)</t><t k="Detailni_8">(4:1,1,1,1)</t><t k="Detailni_9">(4:2,2,2,2)</t><t k="Detailni10">(4:14259095,14259109,14259079,14260778)</t></tags>

[krticka]

So thinking about this more, in tag editor the tags should be divided into read-only (object part) and to editable (tag part).

[dl3sdo]

@krticka:
Yes, I plan to implement comparisons of the actual length/area of objects by adding < <= > >= operators, so a query could be
.PaperArea < 2.4
Right now the keywords are not hierarchical, e.g., .AreaTooSmall .LineTooShort .PaperArea .RealArea .PaperLength .RealLength
I also thought about .Area.TooSmall .Area.Real .Length.Paper .Symbol.Id .Date.LastModified .Date.Created etc.

[dg0yt]

The question to "internal keywords" is mostly driven by the question "What everything I can query?"

Well, the point was: There is no other "keyword" at the moment.

So thinking about this more, in tag editor the tags should be divided into read-only (object part) and to editable (tag part).

SYMBOL is the prototype. It is a special keyword, accessing "read-only tags" (or rather: implicit properties?) when used like

SYMBOL 520

And still it is possible to query "editable tags" (or: explicit properties):

"SYMBOL" = "foobar"

So there isn't really a need to add an unusual prefix. TBH I would be more likely to accept a functional pattern like

SYMBOL() = 520 AND AREA(PAPER) < 10

[dl3sdo]

Now the comparison operations are implemented as well.
@krticka's wish to select objects without symbol is considered as well: .UndefinedSymbol
I added an option to center the view to the found/selected object(s). Maybe this behaviour could be the default (and the checkmark removed)?
The relevant keywords can be selected and inserted easily. The proposed list is not (yet) context sensitive (e.g., don't propose anything after 'SYMBOL' and don't propose AND, OR after AND/OR).
Please note that the keywords are preliminary due to @dg0yt's wish for a different keyword style.

DeleteFindNext2.mp4

[krticka]

Generally works fine, some comments:

• I would prefer the option to center the view to the found/selected object(s) as default.
• Find all - after 2 seconds information about number of selected objects is gone (status bar). This time is too short, maybe to show this information directly in find menu all the time?
• It is possible to use .RealArea/.PaperArea on line symbols what is not logical, e.g. SYMBOL 101.0 AND .RealArea < 10. It is also unclear for me what area it measures - is it the shape of the line + straight line between start and end point creating the area?
• Similarly, it is possible to use .RealLength/.PaperLength on area symbols, but here it's okay if you understand that you are measuring Perimeter. Maybe if you hover the keyword menu can we use notification bubble or activate status bar with short explanation what job keyword does?

[dl3sdo]

When I thought about an extension of this mechanism I came to the same patterns as Kai proposed, e.g. AREA(PAPER).
I propose to have an argument list, e.g., AREA(PAPER;TOOSMALL), LINE(REAL;TOOSHORT), DATE(CREATED), DATE(MODIFIED).
I started a redesign but that will not be available before mid-October.