tzaeschke / phtree-cpp

PH-Tree C++ implementation
Apache License 2.0
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Improve Filter API for multimap #26

Closed tzaeschke closed 2 years ago

tzaeschke commented 2 years ago

Improve the API for PhTreeMultiMap. The current API expects filters that can filter nodes or entries. The multimap uses collections ("buckets") at each coordinate to store multiple values. As a result, the current implementation calls the filter once for every entry in every candidate bucket. This is correct but inefficient.

Many filters will constrain on the coordinate (e.g. FilterSphere). It would be efficient if such a filter would be called only once per bucket, not once per entry in the bucket.

The new API enforces filters with three filter methods:

This change breaks the API.