reprojection of lat/long lines across 180 in mercator map fails

[qgib]

Author Name: Brent Wood (Brent Wood)
Original Redmine Issue: 13380
Affected QGIS version: master
Redmine category:projection_support

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Lines that cross the 180 meridian are wrapped the long way around the world ONLY when the 180 meridian is outside the map extent.

Project CRS=EPSG:3994 (Mercator 41) for maps in the wider New Zealand region.
Optionally open a raster context layer, eg: ftp://ftp.niwa.co.nz/bathymetry/NZBathy_DTM_ascii-grid.zip
Optionally open a vector context layer: eg: ftp://ftp.niwa.co.nz/bathymetry/NZBathy_shape.zip

Open a +-180 EPSG:4326 WFS layer: URL=http://boi.wms.niwa.co.nz/cgi-bin/acoustic_bw layer=TransectAll_180

As long as the 180 meridian is inside the QGIS map canvas extent, lines crossing 180 render correctly. If the map is zoomed or scrolled so that the 180 meridian is outside the canvas extent, the lines wrap across the canvas, essentially traversing the world the long way around.

This appears under several versions of QGIS & appears OS independent.

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• QGIS_180_OK.png (Brent Wood)
• qgis_180_error.png (Brent Wood)
• 214.jpg (Giovanni Manghi)
• master.jpg (Giovanni Manghi)

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Related issue(s): #26213 (duplicates), #27571 (relates)
Redmine related issue(s): 18323, 19746

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[qgib]

Author Name: Brent Wood (Brent Wood)

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can provide some funding - don't know about all though - without a cost estimate.

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• category_id was changed from Browser to Projection Support

[qgib]

Author Name: Giovanni Manghi (@gioman)

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• fixed_version_id removed Version 2.10

[qgib]

Author Name: Saber Razmjooei (@saberraz)

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The WFS is down. Could you try with the latest master and report back?

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• status_id was changed from Open to Feedback

[qgib]

Author Name: Giovanni Manghi (@gioman)

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The issue is old, I wrote this paragraph

http://docs.qgis.org/2.8/en/docs/user_manual/working_with_vector/supported_data.html#vector-layers-crossing-180-degrees-longitude

a looong ago.

Anyway see the attached screenshots (master and 2.14.3), now it seems there is another problem in the WFS client in master, if confirmed a new regression ticket must be filed. Please leave feedback.

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• os_version was changed from Mint 17.1/Win7 to
• operating_system was changed from Linux/Windows to
• 10071 was configured as master.jpg
• 10070 was configured as 214.jpg

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• master.jpg (Giovanni Manghi)
• 214.jpg (Giovanni Manghi)

[qgib]

Author Name: Giovanni Manghi (@gioman)

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Setting it open because there is anyway a lot of room for improvement... is anyway something affects qgis since forever I think.

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• priority_id was changed from High to Normal
• status_id was changed from Feedback to Open

[qgib]

Author Name: Giovanni Manghi (@gioman)

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

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• duplicated was configured as Multi-part Polygon is not mapped with shortest segments #26213

[qgib]

Author Name: Andreas Neumann (@andreasneumann)

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• relates was configured as Disappearing -180 / 180 longitude grid lines on certain zoom levels #27571

[qgib]

Author Name: Giovanni Manghi (@gioman)

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End of life notice: QGIS 2.18 LTR

Source:
http://blog.qgis.org/2019/03/09/end-of-life-notice-qgis-2-18-ltr/

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• resolution was changed from to end of life
• status_id was changed from Open to Closed