Added gaussian blur, some refactor, fast gaussian, fix MSVC M_PI build #68

	permissions: read-all

	name: Build / test

	on:
	push:
	branches:
	- '*'
	- '!ci_test_*'
	tags-ignore:
	- '*'
	pull_request:
	branches:
	- '*'
	- '!ci_test_*'

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	jobs:
	cmake_ubuntu_2204:
	name: Build and test ${{ matrix.name }}
	runs-on: ubuntu-22.04
	strategy:
	matrix:
	include:
	- name: Clang-15 (C++20)
	extra_deps: clang-15
	c_compiler: clang-15
	cxx_compiler: clang++-15
	cxx_standard: 20

	- name: GCC-11 (C++20)
	extra_deps: g++-11
	c_compiler: gcc-11
	cxx_compiler: g++-11
	cxx_flags: -ftrapv
	cxx_standard: 20

	- name: GCC-12 (C++20)
	extra_deps: g++-12
	c_compiler: gcc-12
	cxx_compiler: g++-12
	cxx_flags: -ftrapv
	cxx_standard: 20

	steps:
	- name: Harden Runner
	uses: step-security/harden-runner@63c24ba6bd7ba022e95695ff85de572c04a18142 # v2.7.0
	with:
	egress-policy: audit # cannot be block - runner does git checkout

	- uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.0.0

	- name: Install deps
	run: sudo apt-get install ${{ matrix.extra_deps }} git

	- name: Build and test
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	run: \|
	export CMAKE_BUILD_PARALLEL_LEVEL=2
	export CTEST_PARALLEL_LEVEL=2
	git clone --branch widen_mul https://token:${GITHUB_TOKEN}@github.com/awxkee/highway
	CXXFLAGS=${{ matrix.cxx_flags }} CC=${{ matrix.c_compiler }} CXX=${{ matrix.cxx_compiler }} cmake -DCMAKE_CXX_STANDARD=${{ matrix.cxx_standard }} -B out .
	cmake --build out
	ctest --test-dir out

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