[Framework] Apply template method design pattern to Contact

[NiziL]

SED Sprint 2025

Base class Contact, function modified:

• getCollisionModels
• setDetectionOuputs
• createResponse
• removeResponse

Child classes modified:

• Sofa: components
  • BarycentricStickContact
  • BarycentricPenaltyContact
  • BaseUnilateralContactResponse
  • RayContact
  • StickContactConstraint

• child class RegistrationContact modified in Registration plugin (see below)

[ci-depends-on https://github.com/sofa-framework/Registration/pull/24]

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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).

[sofabot]

[ci-depends-on] detected during build #1.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[sofabot]

[ci-depends-on] detected during build #2.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[sofabot]

[ci-depends-on] detected during build #3.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[sofabot]

[ci-depends-on] detected during build #4.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[sofabot]

[ci-depends-on] detected during build #5.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[sofabot]

[ci-depends-on] detected during build #6.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[NiziL]

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

[sofabot]

[ci-depends-on] detected during build #7.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[damienmarchal]

I'm not sure it makes sens to move from absrtact method to a virtual final. Shouldn't it be a non virtual one ? (same comment apply everywhere)

[NiziL]

I'm going to talk about this to the team during the daily meeting, might apply to all the SED Sprint PRs

[NiziL]

@damienmarchal Talked about it with the team, for us it's important to declare them as virtual final to ensure child class cannot shadow them.

[bakpaul]

Yes, I confirm, putting virtual final will make sure no one override it

[alxbilger]

@damienmarchal's point is pertinent but the context must be taken into account:
The function createResponse was virtual. There are chances that someone overloaded this function in a derived class. And there are two cases:

1. The overload has the override keyword:
   • if the base class function is virtual final, it will trigger a compilation error because of a final method cannot be overloaded.
   • If the base class function is a non-virtual function, it will also trigger a compilation error because there is nothing to override.
2. The overload has not the override keyword:
   • if the base class function is virtual final, it will trigger a compilation error because it tries to override a final function.
   • If the base class function is a non-virtual function, the function in the derived class will be valid. And that's not what we want. We want to notice the derived class that something changed and the code must be adapted. This case will not notice the developer of the derived class, and will introduce a bug.

Because of that, virtual final is not silly. However, this case should be rare because the override keyword should be widely used. So going with a non-virtual function should not be risky, and be the objective.

[sofabot]

[ci-depends-on] detected during build #8.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[sofabot]

[ci-depends-on] detected during build #9.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='bdd6b0fbd05c450611612662021173fb25c1cc45'

[sofabot]

[ci-depends-on] detected during build #10.

To unlock the merge button, you must

• Merge or close [Framework] Apply template method design pattern to Contact Registration#24
  For this build, the following CMake flags will be set
  -DREGISTRATION_GIT_REPOSITORY='https://github.com/sofa-framework/Registration'
  -DREGISTRATION_GIT_TAG='c0d59cb0af63b01b4385e470ad77c8fd17c3c47d'