* Move grab brush preview method to `grab.cc`
* Use `enum class` where possible
* Use `const` where possible
* Use C++ math libraries where possible
* float3 instead of float *
* numeric limits & constexpr instead of macros
* Clarify naming of some variables
* Add doxygen sections
Pull Request: https://projects.blender.org/blender/blender/pulls/127743
b70c00bf4e