Performance during digitizing in a shape-layer if other big layers in project are snap-able

[qgib]

Author Name: Joachim Deutmann (Joachim Deutmann)
Original Redmine Issue: 6876
Affected QGIS version: 1.8.0
Redmine category:digitising

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Layer with many elements reduce performance during digitizing in the project significantly if the layers snap is on. This applies to all of the tested file formats or databases (Shape, XML, KML, SpatiaLite, PostgreSQL ...) If these layers, however, saved as MapInfo Tab layer, the performance increases drastically. For example, i generate a vector grid with 170,000 polygons and stored it as well as ESRI-shape and as MapInfo-tab. Both layers are in the actual project. After that i create a new polygon-shape layer in the same project. Then i turn "snap on" on the big TAB-Layer and create an object in new shape layer (It doesn't matter, if it is created "normal" or with the plugin "new memory layer" or if it is an existing Shapelayer). The performance difference between snap on the TAB-layer (high speed) and snap on the SHP-layer (very, very slow) during digitizing is extreme.

[qgib]

Author Name: Giovanni Manghi (@gioman)

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• priority_id was changed from High to Normal

[qgib]

Author Name: Giovanni Manghi (@gioman)

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• easy_fix was configured as 0
• regression was configured as 0

[qgib]

Author Name: Giovanni Manghi (@gioman)

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Please test with a recent QGIS release (2.18 or 3), if the issue/request is still valid change the affected version accordingly, if is fixed/implemented then close the ticket. Thanks!

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• status_id was changed from Open to Feedback

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• resolution was changed from to no timely feedback
• status_id was changed from Feedback to Closed