[All] Propose a new gravity API

[hugtalbot]

This pull request aims at making the gravity clearly appearing in object nodes as a GravityForceField.
Old way to define gravity still works and is not deprecated.

Main changes:

• By implementing this, the Mass is not inheriting from ForceField anymore.
• The optional mechanism of a separate gravity and the Gravity class are also deprecated.
• Default gravity is now 0 (therefore some scenes might fail and need an update)

The GravityForceField can:

• either be manually added by the user in the node
• or the gravity can still be globally defined in the root node which will create the automatic creation of a GravityForceField for each mass in the graph

Fix: #2683

[ci-depends-on https://github.com/sofa-framework/SofaPython3/pull/305]
[ci-depends-on https://github.com/sofa-framework/BeamAdapter/pull/56]
[ci-depends-on https://github.com/sofa-framework/ci/pull/18]

---

By submitting this pull request, I acknowledge that
I have read, understand, and agree SOFA Developer Certificate of Origin (DCO).

---

Reviewers will merge this pull-request only if

• it builds with SUCCESS for all platforms on the CI.
• it does not generate new warnings.
• it does not generate new unit test failures.
• it does not generate new scene test failures.
• it does not break API compatibility.
• it is more than 1 week old (or has fast-merge label).

[hugtalbot]

[ci-build][with-all-tests]

[sofabot]

[ci-depends-on] detected during build #16.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 73de20be7773ab0902fa15b17a01d08839b2ec60
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 30200f8e1e51c09cefcb50b073f9b6756159c10f

[sofabot]

[ci-depends-on] detected during build #17.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80

[hugtalbot]

What was written above (hidden by GH):

---

TODO:

• test when a node is added

One issue remains in my tests :

• simulation starting without gravity, and then gravity is added
• mass added using python, since no init, the link in GravityForceField to the local mass is no performed

[sofabot]

[ci-depends-on] detected during build #18.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80
• Merge or close Remove depreacted plugin from script ci#18
  For this build, ci/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/ci
  GIT_TAG 0570c25092434d8d734ebdafae5a21ece68bf320

[hugtalbot]

[ci-build][with-all-tests]

[sofabot]

[ci-depends-on] detected during build #19.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80
• Merge or close Remove depreacted plugin from script ci#18
  For this build, ci/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/ci
  GIT_TAG cdb80f16c5700c381353f4bd4b99e05ff8065560

[sofabot]

[ci-depends-on] detected during build #20.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80
• Merge or close Remove depreacted plugin from script ci#18
  For this build, ci/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/ci
  GIT_TAG cdb80f16c5700c381353f4bd4b99e05ff8065560

[hugtalbot]

[ci-build][with-all-tests][force-full-build]

[sofabot]

[ci-depends-on] detected during build #21.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80
• Merge or close Remove depreacted plugin from script ci#18
  For this build, ci/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/ci
  GIT_TAG cdb80f16c5700c381353f4bd4b99e05ff8065560

[fredroy]

[ci-build][with-all-tests][force-full-build]

[sofabot]

[ci-depends-on] detected during build #22.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80

[sofabot]

[ci-depends-on] detected during build #23.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80

[sofabot]

[ci-depends-on] detected during build #24.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80

[sofabot]

[ci-depends-on] detected during build #25.

To unlock the merge button, you must

• Merge or close [binding] Make Mass binding compatible with #2988 SofaPython3#305
  For this build, SofaPython3/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/SofaPython3
  GIT_TAG 941eea2a17f394574ca0f5449a8221ef43c201bf
• Merge or close [forcefield] Update ForceFieldAndMass to be compatible with #2988 BeamAdapter#56
  For this build, BeamAdapter/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/BeamAdapter
  GIT_TAG 821cd35912044ce84a89eb401be168a8ff70db80

[hugtalbot]

Not enough convincing arguments to bring such a breaking feature into SOFA
Let's discuss and possibly close it at next STC#15