Added Proj integration

[michalpelka]

I am publishing current state of proj integration.
It seems to improve quality of geographics conversions (I am comparing it to airborne Lidar).

However I have some misaligment in height (about 3-5 meters):

I am consulting with experts in the field. It seems that is result of GNSS receiver in test data.

About this change:

• I am adding Proj similar to opencv (download binaries on Windows, get from apt on Linux).
• I've wrote CI pipeline to build Proj in github actions.
• I've fixed height in pose grahp slam for GNSS.

What need to be done:

• fixes for Linux build.

[michalpelka]

I do not have idea how to install proj on Mac.

[michalpelka]

Done research, I am little less stupid.

I think I understand what’s happening. The GPSA fix is the WGS84 height.
But the NMEA GGA message, in the alt field, has: “Antenna altitude above/below mean sea level.”
In the following fields there is the parameter u: “Undulation – the relationship between the geoid and the WGS84 ellipsoid.”

So you need to subtract (or add) u to alt to obtain the ellipsoidal height.

The data confirms this (from our system):
11984423415770 1747581809550 $GNGGA,092656.000,5036.007407,N,02258.318671,E,1,08,2.42,231.474,M,38.832,M,,*76
231.474 is the height above mean sea level.
38.832 is the geoid height above the ellipsoid.

The difference I’m seeing now in HDMapping is due to the fact that the mean sea level used in NMEA does not match the mean sea level used in ISOK.

[JanuszBedkowski]

Done research, I am little less stupid.

I think I understand what’s happening. The GPSA fix is the WGS84 height. But the NMEA GGA message, in the alt field, has: “Antenna altitude above/below mean sea level.” In the following fields there is the parameter u: “Undulation – the relationship between the geoid and the WGS84 ellipsoid.”

So you need to subtract (or add) u to alt to obtain the ellipsoidal height.

The data confirms this (from our system): 11984423415770 1747581809550 $GNGGA,092656.000,5036.007407,N,02258.318671,E,1,08,2.42,231.474,M,38.832,M,,*76 231.474 is the height above mean sea level. 38.832 is the geoid height above the ellipsoid.

The difference I’m seeing now in HDMapping is due to the fact that the mean sea level used in NMEA does not match the mean sea level used in ISOK.

Michal --> this is very significant step to City Level mapping! Many THX

[michalpelka]

I had to update runner to ubuntu 24.04 - 22.04 had ancient proj in apt.

[michalpelka]

It is ready for review! Ready for testing!

[michalpelka]

here is how it looks like:

[Copilot]

Pull request overview

This PR integrates the PROJ library into the project to improve GNSS/geographic coordinate conversions and adds UI support for exporting data in multiple coordinate reference systems (with optional geoid models). It also updates CI and build scripts to install/link PROJ and adjusts GNSS usage in pose-graph SLAM to use the newly introduced projected coordinates.

Changes:

• Add PROJ build integration (CMake + 3rd-party binary fetch on Windows; system dependency on Linux) and link it into core and the GUI app.
• Refactor GNSS loading/projection APIs and migrate internal usage from x/y/alt to enu_x/enu_y/enu_z.
• Update GitHub Actions workflows and Ubuntu dependency scripts to include libproj-dev and use Ubuntu 24.04 runners.

Reviewed changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated 19 comments.

Show a summary per file

File	Description
ubuntu-24.04-apt-requirements.sh	Adds libproj-dev to Ubuntu apt requirements.
core/src/pose_graph_loop_closure.cpp	Switches pose-graph GNSS fusion to use enu_* coordinates.
core/src/gnss.cpp	Adds PROJ-based projection/unprojection, geoid discovery, CRT conversion, and migrates GNSS fields to enu_*.
core/include/gnss.h	Updates GNSS API and data model (enu_*), adds CRT identifiers and new conversion APIs.
core/CMakeLists.txt	Links core targets against PROJ.
apps/multi_view_tls_registration/multi_view_tls_registration_gui.cpp	Updates GNSS import/export UI to use new GNSS APIs; adds geoid/CRT export options.
apps/multi_view_tls_registration/CMakeLists.txt	Links the GUI executable against PROJ.
CMakeLists.txt	Includes new PROJ setup script.
3rdpartyBinary/Proj/CMakeLists.txt	Adds PROJ discovery on Linux and prebuilt download on Windows.
.gitignore	Ignores additional build directories.
.github/workflows/python-bindings-linux.yml	Moves to ubuntu-24.04 and installs libproj-dev.
.github/workflows/cmake-linux.yml	Moves to ubuntu-24.04, installs libproj-dev, and adjusts PKG_CONFIG_PATH.
.github/workflows/cmake-linux-deb.yml	Moves to ubuntu-24.04 and installs libproj-dev.

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