Timeline for qgis2 - hide a layer (or its labels) when another layer is coincident?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 10, 2014 at 8:57 | comment | added | HeikkiVesanto♦ | Although it seems a contains query cannot be done on two line layers in QGIS. So you best option would be to re segment the lines and do an "equals" query. | |
| Feb 10, 2014 at 8:51 | comment | added | HeikkiVesanto♦ | A good example of the possible spatial queries can be found at: gaia-gis.it/spatialite-2.3.1/spatialite-tutorial-2.3.1.html Section 4.2 So you might want to do a "Contains" query to find the ones that do not need to be segmented. But I don't think you can do the query in the label expression. Labels are powerful and data driven, but do not have access to the spatial queries. | |
| Feb 10, 2014 at 6:04 | comment | added | Tom Grundy | Thinking about that, it wouldn't be practical to resegment all the upper layer roads to match the segmentation of the lower layer roads. Seems like it's a matter of the boolean logic in the spatial query: is there a way to check for 'partial overlaps', i.e. 'select lower layer objects that have all their points coincident with any upper layer object'? (or ultimately eliminate the need for the manual spatial query and find a syntax in the label expression to do all this) | |
| Feb 10, 2014 at 5:49 | comment | added | Tom Grundy | I'm only getting a couple of result selections from the spatial query plugin, and it might be because the objects on the upper layer are merged together while the objects on the lower layer are segmented at each road intersection. So, the filters for crosses, equals, intersects, overlaps, and touches all return only a few selections, where there are actually hundreds of road segments that overlap. I'll try to get the segmentations identical and see if that does the trick... | |
| Feb 8, 2014 at 1:33 | comment | added | Tom Grundy | yes, sorry, it's in the queue to try this out but schedule here has been slammed. I'll definitely follow up here. Thanks | |
| Jan 31, 2014 at 16:32 | history | answered | HeikkiVesanto♦ | CC BY-SA 3.0 |