This commit applies the following changes: * Use c++ math types instead of float / int arrays where possible * Use c++ math library where c++ math types are used * Use const where possible * Reduces scope of variables where possible * Clarifies some variable naming (e.g. d prefix to _delta suffix) The main areas left untouched are anything that is part of a public function signature to avoid making changes in many different files at once. Pull Request: https://projects.blender.org/blender/blender/pulls/129576