daniel86 · daniel86 · Jan 1, 2026 · Dec 30, 2025 · Dec 30, 2025 · Dec 30, 2025
diff --git a/.github/actions/setup-linux/action.yml b/.github/actions/setup-linux/action.yml
@@ -0,0 +1,19 @@
+name: Setup Linux build environment
+description: Install dependencies
+runs:
+  using: "composite"
+  steps:
+    - shell: bash
+      run: |
+        set -euo pipefail
+        sudo apt-get update -y -qq
+        sudo apt-get install libgl-dev \
+            libboost-thread-dev libboost-system-dev libboost-date-time-dev libboost-filesystem-dev \
+            libboost-regex-dev libboost-timer-dev libsimde-dev \
+            libassimp-dev libopenal-dev libdevil-dev libfreetype-dev libbullet-dev \
+            libglew-dev libglu1-mesa-dev libgl1-mesa-dev \
+            libavcodec-dev libavformat-dev libavutil-dev libswscale-dev \
+            libpng-dev libalut-dev \
+            qtbase5-dev libgtest-dev \
+            doxygen graphviz \
+            nlohmann-json3-dev
diff --git a/.github/workflows/main.yml → .github/workflows/ci-linux.yml b/.github/workflows/main.yml → .github/workflows/ci-linux.yml
@@ -1,5 +1,4 @@
-
-name: CI
+name: CI Linux
 on:
   push:
     branches: [ dev ]
@@ -8,44 +7,32 @@ on:
   release:
     types: [published]
 jobs:
-  build:
+  ##############################
+  build-linux:
     runs-on: ubuntu-24.04
     steps:
-    # Note: some steps require the checkout in the root directory
     - uses: actions/checkout@v3
+    - uses: ./.github/actions/setup-linux
     - name: Build REGEN workspace
       shell: bash
       run: |
-        sudo apt-get update -y -qq
-        sudo apt-get install libgl-dev \
-            libboost-thread-dev libboost-system-dev libboost-date-time-dev libboost-filesystem-dev \
-            libboost-regex-dev libboost-timer-dev \
-            libassimp-dev libopenal-dev libdevil-dev libfreetype-dev libbullet-dev \
-            libglew-dev libglu1-mesa-dev libgl1-mesa-dev \
-            libavcodec-dev libavformat-dev libavutil-dev libswscale-dev \
-            libpng-dev libalut-dev \
-            qtbase5-dev libgtest-dev \
-            doxygen graphviz \
-            nlohmann-json3-dev
+        set -euo pipefail
         mkdir build
         cd build
-        cmake ../ -DCMAKE_BUILD_TYPE=Release -DBUILD_TESTS=ON -DBUILD_VIDEO_PLAYER=ON
-        make 2> >(tee "make-output.txt")
+        cmake ../ \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DBUILD_UNIT_TESTS=ON \
+          -DBUILD_TESTS=ON \
+          -DBUILD_VIDEO_PLAYER=ON
+        make -j$(nproc) 2> >(tee "make-output.txt")
     - name: Annotate compilation warnings/errors
       if: ${{github.event_name == 'pull_request'}}
       uses: JacobDomagala/CompileResult@master
       # just so that in case this step fails, the workflow doesn't stop.
-      # this is done as it is unclear how well the action is maintained.
       continue-on-error: true
       with:
         comment_title: Compilation
         compile_result_file: build/make-output.txt
-    - name: Create debian package
-      if: ${{github.event_name == 'push' || github.event_name == 'release'}}
-      shell: bash
-      run: |
-        cd build
-        cpack
     - name: Run unit tests
       if: ${{github.event_name == 'push' || github.event_name == 'pull_request'}}
       shell: bash
@@ -59,12 +46,55 @@ jobs:
         junit_files: "gtest-regen.xml"
         action_fail: true
         action_fail_on_inconclusive: true
-    #####
+    - name: Upload test results
+      uses: actions/upload-artifact@v4
+      with:
+        name: test results
+        path: ./gtest-regen.xml
+  ##############################
+  debian-package:
+    needs: build-linux
+    runs-on: ubuntu-24.04
+    steps:
+    - uses: actions/checkout@v3
+    - uses: ./.github/actions/setup-linux
+    - name: Create debian package
+      if: ${{github.event_name == 'push' || github.event_name == 'release'}}
+      shell: bash
+      run: |
+        set -euo pipefail
+        mkdir build
+        cd build
+        cmake ../ -DCMAKE_BUILD_TYPE=Release
+        cpack
+    - name: Release debian package
+      if: github.event_name == 'release'
+      shell: bash
+      env:
+        GITHUB_TOKEN: ${{ github.TOKEN }}
+      run: |
+        gh release upload ${{github.event.release.tag_name}} ./build/regen-*.deb
+    - name: Upload debian package
+      if: github.event_name == 'push'
+      uses: actions/upload-artifact@v4
+      with:
+        name: debian package
+        path: ./build/regen-*.deb
+  ##############################
+  doxygen:
+    needs: build-linux
+    runs-on: ubuntu-24.04
+    steps:
+    - uses: actions/checkout@v3
+    - uses: ./.github/actions/setup-linux
     - name: Run doxygen
       if: ${{github.event_name == 'push' || github.event_name == 'release'}}
       shell: bash
       run: |
+        set -euo pipefail
+        mkdir build
         cd build
+        cmake ../ -DCMAKE_BUILD_TYPE=Release
         cmake --build . --target doc
         cp -r ../img regen/doc/html/
     - name: Extract version tag
@@ -88,26 +118,3 @@ jobs:
         BRANCH: gh-pages
         # The folder the action should deploy.
         FOLDER: build/regen/doc/html
-        # The folder in the target branch
-        TARGET_FOLDER: ${{ env.REGEN_DOCU_VERSION }}
-        CLEAN: true
-        SINGLE_COMMIT: true
-    #####
-    - name: Release debian package
-      if: github.event_name == 'release'
-      shell: bash
-      env:
-        GITHUB_TOKEN: ${{ github.TOKEN }}
-      run: |
-        gh release upload ${{github.event.release.tag_name}} ./build/regen-*.deb
-    - name: Upload debian package
-      if: github.event_name == 'push'
-      uses: actions/upload-artifact@v4
-      with:
-        name: debian package
-        path: ./build/regen-*.deb
-    - name: Upload test results
-      uses: actions/upload-artifact@v4
-      with:
-        name: test results
-        path: ./gtest-regen.xml
diff --git a/.github/workflows/ci-macos.yml b/.github/workflows/ci-macos.yml
@@ -0,0 +1,29 @@
+name: CI MacOS
+on:
+  push:
+    branches: [ dev ]
+  pull_request:
+    branches: [ dev ]
+  release:
+    types: [published]
+
+jobs:
+  build-macos:
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Install dependencies
+        run: |
+          brew install cmake gcc simde boost assimp openal-soft freetype bullet glew qt5 doxygen graphviz devil ffmpeg alut nlohmann-json googletest
+      - name: Build REGEN workspace
+        run: |
+          mkdir build
+          cd build
+          cmake \
+            -DCMAKE_C_COMPILER=/opt/homebrew/bin/gcc-14 -DCMAKE_CXX_COMPILER=/opt/homebrew/bin/g++-14 \
+            -DCMAKE_PREFIX_PATH="/opt/homebrew/opt/qt@5" \
+            -DCMAKE_BUILD_TYPE=Release \
+            -DBUILD_TESTS=ON \
+            -DREGEN_EXTRA_INCLUDE_DIRS="/opt/homebrew/opt/openal-soft/include/" \
+            ../
+          make
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -75,8 +75,10 @@ endif()
 # given in the books "Effective C++" and "More Effective C++"
 # add_definitions( -Weffc++ )
 
-if(UNIX) # gcc options
-    add_definitions( -mfpmath=sse -march=native )
+if(UNIX)
+    # -march=native enables all instruction subsets supported by the local machine
+    # e.g. SSE2, SSE3, SSE4, AVX, AVX2, etc.
+    add_definitions( -march=native )
 endif()
 
 # perform more aggressive floating-point optimizations
@@ -107,6 +109,10 @@ find_package(Boost ${Boost_MIN_VERSION}
 find_package(Threads REQUIRED)
 # Font library: text rendering support
 find_package(Freetype REQUIRED)
+# Note: On Linux, it seems needed in addition to link against brotlidec
+if (UNIX AND NOT APPLE)
+    set(FREETYPE_LIBRARIES ${FREETYPE_LIBRARIES} -lbrotlidec)
+endif()
 # JSON library: for serialization
 find_package(nlohmann_json REQUIRED)
 set(JSON_LIBRARIES nlohmann_json::nlohmann_json)
@@ -184,8 +190,10 @@ message(STATUS "  Models:${ASSIMP_INCLUDE_DIRS};")
 message(STATUS "  Fonts:${FREETYPE_INCLUDE_DIRS};")
 message(STATUS "  Physics:${BULLET_INCLUDE_DIRS};")
 
-enable_testing()
-find_package(GTest REQUIRED)
+if (BUILD_UNIT_TESTS)
+    enable_testing()
+    find_package(GTest REQUIRED)
+endif ()
 
 if (HAS_AV_LIBS)
     # allow includes without AL/ prefix. Some openAL versions require this.
@@ -199,7 +207,7 @@ set(REGEN_LIBRARIES
     ${Boost_LIBRARIES}
     ${JSON_LIBRARIES}
     ${ASSIMP_LIBRARIES}
-    ${FREETYPE_LIBRARIES} -lbrotlidec
+    ${FREETYPE_LIBRARIES}
     ${IMG_LIBRARIES}
     ${AV_LIBRARIES}
     ${CMAKE_THREAD_LIBS_INIT}
@@ -239,6 +247,10 @@ endif()
 ###########
 ###########
 
+if(REGEN_EXTRA_INCLUDE_DIRS)
+    include_directories(${REGEN_EXTRA_INCLUDE_DIRS})
+endif()
+
 # allow includes like <regen/xxx.h> even if the engine is not installed
 include_directories(.)
 # allow include of generated files
@@ -260,19 +272,21 @@ install(FILES img/icon-small.png DESTINATION ${SHARE_INSTALL_PATH}/img)
 ########## Unit Testings
 ##############
 
-# add an executable target for GTest.
-# but the testing code is partly in the *knowrob* library
-# where gtest won't find them without using the "--no-as-needed"
-# flag for the linker.
-add_executable(all_gtests
-        tests/gtests.cpp
-        tests/shapes/quad-tree-test.cpp)
-target_link_libraries(all_gtests
-        -Wl,--whole-archive,--no-as-needed
-        regen
-        -Wl,--no-whole-archive
-        ${Boost_Python_COMPONENT}
-        ${GTEST_MAIN_LIBRARIES})
+if (BUILD_UNIT_TESTS)
+    # add an executable target for GTest.
+    # but the testing code is partly in the *knowrob* library
+    # where gtest won't find them without using the "--no-as-needed"
+    # flag for the linker.
+    add_executable(all_gtests
+            tests/gtests.cpp
+            tests/shapes/quad-tree-test.cpp)
+    target_link_libraries(all_gtests
+            -Wl,--whole-archive,--no-as-needed
+            regen
+            -Wl,--no-whole-archive
+            ${Boost_Python_COMPONENT}
+            ${GTEST_MAIN_LIBRARIES})
+endif ()
 
 ##############
 ########## packaging

diff --git a/README.md b/README.md
@@ -10,7 +10,13 @@
     <img src="img/gallery.gif" width="160" height="100" />
 </p>
 
-![CI](https://github.com/daniel86/regen/workflows/CI/badge.svg)
+![Linux](https://github.com/daniel86/regen/actions/workflows/ci-linux.yml/badge.svg)
+![MacOS](https://github.com/daniel86/regen/actions/workflows/ci-macos.yml/badge.svg)
+![Warnings](https://img.shields.io/badge/compiler%20warnings-clean-brightgreen)
+[![Docs](https://img.shields.io/badge/docs-online-blue)](https://daniel86.github.io/regen/)
+![Debian](https://img.shields.io/badge/debian-.deb%20package-blue)
+![GitHub release](https://img.shields.io/github/v/release/daniel86/regen?include_prereleases)
+![License](https://img.shields.io/github/license/daniel86/regen)
 
 `regen` -- **Real-time Graphics Engine** -- is a modular OpenGL-based C++ engine designed for research and experimentation in real-time rendering, GPU compute, and virtual world simulation.
 

diff --git a/regen/compute/radix-sort-cpu.h b/regen/compute/radix-sort-cpu.h
@@ -139,31 +139,31 @@ namespace regen {
 					if constexpr (KEY_TYPE_BITS == 16) {
 						// Gather 8 keys manually, and promote to 32-bit
 						for (int k = 0; k < 8; ++k) tmpKeys32[k] = static_cast<int32_t>(keys[src[keyIdx+k]]);
-						r0 = _mm256_load_si256(reinterpret_cast<const __m256i*>(tmpKeys32));
-						r0 = _mm256_and_si256(_mm256_srli_epi32(r0, SHIFT), mask);
+						r0 = simde_mm256_load_si256(reinterpret_cast<const simde__m256i*>(tmpKeys32));
+						r0 = simde_mm256_and_si256(simde_mm256_srli_epi32(r0, SHIFT), mask);
 						keyIdx += 8; // processed 8 keys, not 16!
 					}
 					else if constexpr (KEY_TYPE_BITS == 32) {
-						simd::Register_i idx = _mm256_loadu_si256(reinterpret_cast<const __m256i*>(&src[keyIdx]));
+						simd::Register_i idx = simde_mm256_loadu_si256(reinterpret_cast<const simde__m256i*>(&src[keyIdx]));
 						// Gather 8 scattered keys, and apply shift and mask to get bucket ids
-						r0 = _mm256_i32gather_epi32(reinterpret_cast<const int*>(keys), idx, 4);
-						r0 = _mm256_and_si256(_mm256_srli_epi32(r0, SHIFT), mask);
+						r0 = simde_mm256_i32gather_epi32(reinterpret_cast<const int*>(keys), idx, 4);
+						r0 = simde_mm256_and_si256(simde_mm256_srli_epi32(r0, SHIFT), mask);
 						keyIdx += KEYS_PER_SIMD_PASS;
 					}
 					else if constexpr (KEY_TYPE_BITS == 64) {
 						// note: values have 32 bits, use __m128i to load only 4
-						__m128i idx32 = _mm_loadu_si128(reinterpret_cast<const __m128i*>(&src[keyIdx]));
+						simde__m128i idx32 = simde_mm_loadu_si128(reinterpret_cast<const simde__m128i*>(&src[keyIdx]));
 						// Gather 4 scattered keys, and apply shift and mask to get bucket ids
-						r0 = _mm256_i32gather_epi64(reinterpret_cast<const long long*>(keys), idx32, 8);
-						r0 = _mm256_and_si256(_mm256_srli_epi64(r0, SHIFT), mask);
+						r0 = simde_mm256_i32gather_epi64(reinterpret_cast<const long long*>(keys), idx32, 8);
+						r0 = simde_mm256_and_si256(simde_mm256_srli_epi64(r0, SHIFT), mask);
 						keyIdx += KEYS_PER_SIMD_PASS;
 					}
 					else {
 						static_assert("Unsupported key size for SIMD radix sort");
 						break;
 					}
 					// Store results into tmpBins_ and increment histogram
-					_mm256_storeu_si256(reinterpret_cast<__m256i*>(tmpBins_), r0);
+					simde_mm256_storeu_si256(reinterpret_cast<simde__m256i*>(tmpBins_), r0);
 					for (auto x : tmpBins_) ++histogram_[x];
 				}
 			}