filters: address TODOs for getMinMax3D to be templated and optimized

[Stado1]

This PR addresses the TODOs for getMinMax3D functions for PCLPointCloud2 to improve performance and allow for different types than just float to be used.

• implemented templates:

  • Moved functions from voxel_grid.cpp to voxel_grid.hpp and templated them on T (for XYZ) and D (for distance fields). This fixes the TODO for only using float types.

• Performance Optimization:

  • Added is_dense checks to skip std::isfinite calls when the cloud is guaranteed to be dense.
  • Moved a couple of operations outside of the for loop to avoid repeated operations.
  • Replaced Eigen::Array4f with separate variables of type T ( x, y, z).

[Copilot]

Pull request overview

This PR refactors the pcl::getMinMax3D overloads for pcl::PCLPointCloud2 to address TODOs by templating coordinate/distance types and applying a few micro-optimizations (e.g., skipping finiteness checks for dense clouds).

Changes:

• Removed the non-templated PCLPointCloud2 getMinMax3D implementations from filters/src/voxel_grid.cpp.
• Replaced the exported non-template declarations in voxel_grid.h with templated declarations for PCLPointCloud2.
• Added the new templated PCLPointCloud2 getMinMax3D definitions into filters/include/pcl/filters/impl/voxel_grid.hpp, plus minor formatting cleanups.

Reviewed changes

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

File	Description
filters/src/voxel_grid.cpp	Deletes the previous float-only PCLPointCloud2 min/max implementations (now moved to templates).
filters/include/pcl/filters/voxel_grid.h	Replaces exported non-template API with template declarations for PCLPointCloud2 overloads.
filters/include/pcl/filters/impl/voxel_grid.hpp	Adds templated PCLPointCloud2 min/max implementations and dense-branch optimizations.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.