landmarks can now be defined with respect to a camera geometric frame instead of the world geometric frame

[servantftransperfect]

A new parameter to landmarks is added "referenceViewId".

For a landmark, if this parameter is not UndefinedIndexT, this is considered as the reference view index for this landmark.

In this case, the landmark coordinates will be considered to be relative to the reference view geometric frame.

[fabiencastan]

This needs a unit test to validate the behavior on simple generated data.

[Copilot]

Pull Request Overview

This PR adds support for landmarks to be defined relative to a camera's geometric frame instead of the world frame. The new referenceViewIndex parameter enables landmarks to store their coordinates relative to a specific camera view, which requires coordinate transformations during bundle adjustment.

• New referenceViewIndex field added to landmarks for specifying reference camera frame
• Updated serialization/deserialization to handle the new reference view parameter
• Added projection cost function for relative landmarks with coordinate transformation logic

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
Landmark.hpp	Adds referenceViewIndex field and updates equality operator
jsonIO.cpp	Adds JSON serialization support for referenceViewIndex
AlembicImporter.cpp	Imports referenceViewIndex from Alembic format
AlembicExporter.cpp	Exports referenceViewIndex to Alembic format
projection.hpp	New ProjectionRelativeErrorFunctor for relative landmark projections
BundleAdjustmentCeres.cpp	Integrates relative projection cost function into bundle adjustment
bundleAdjustment_test.cpp	Adds test case for relative landmark bundle adjustment
NViewDataSet.hpp	Adds useRelative configuration flag for test datasets

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[simogasp]

Shouldn't there be a check everywhere we e.g. reproject landmarks into an image to take into account the relative view (or discard it if it is not supported)?

[servantftransperfect]

Shouldn't there be a check everywhere we e.g. reproject landmarks into an image to take into account the relative view (or discard it if it is not supported)?

We are adding multiple things in successive PR. I do agree that we should but this will be a future effort which will rely on heavy modifications.