Fix Topological editing when CRS are different

[lbartoletti]

Description

The addTopologicalPoints methods attempt to add points without checking the CRS -- which makes sense. So, Topology editing does not work when layers have different CRS.

There are several problems when we use on-the-fly projection, the first is that points are not added when a layer has a different CRS. fix 1

The second one is that when we want to snap to a segment of a layer with a different CRS, it will snap to a vertex (the calculation is done with different coordinates), this is the original request of #29648

Fix 1. Add topological points on layer with a different CRS

before

after

Fix 2. Fix topological editing when CRS are different

before

after

TODO:

• other tools will be fixed in dedicated PR to avoid some confusion
• fix other issue pointed by Topological editing not working when the data CRS is different from project CRS #29648
• test

[nyalldawson]

Is this ready for review?

[lbartoletti]

Is this ready for review?

Yes please. I need to fix other maptools, but I prefer to do this in separated PRs.
The test fail on Travis, but don't know why -- it works on my machine (r)(tm). Do you think this can be related to the proj version (I use proj 7 on my machine)?

[nyalldawson]

Do you think this can be related to the proj version (I use proj 7 on my machine)?

Quite possibly - if you wait till the Github Actions PR is merged then we can re-test...

[lbartoletti]

Do you think this can be related to the proj version (I use proj 7 on my machine)?

Quite possibly - if you wait till the Github Actions PR is merged then we can re-test...

It depends, I'll need this PR to fix the other tools. Maybe I can disable the test for now and I note to readd tests when the GH Actions PR is merged?

[nyalldawson]

@lbartoletti it's really not far off - likely a matter of hours

[nyalldawson]

@lbartoletti if you rebase against master now and force push you'll get the new github workflow

[lbartoletti]

Seems to be OK @nyalldawson ?

[lbartoletti]

Thanks @nyalldawson