Generate Python wheels in CI

.github/workflows/python.yml

@@ -0,0 +1,128 @@
+name: python
+
+on:
+  push:
+    paths-ignore:
+      - '**.md'
+  pull_request:
+    paths-ignore:
+      - '**.md'
+  workflow_dispatch:
+
+jobs:
+  # Generate the sdist first. We'll use it to create the wheels.
+  # https://packaging.python.org/en/latest/flow#the-source-distribution-sdist
+  sdist:
+    name: Generate Source Distribution
+    runs-on: ubuntu-latest
+    outputs:
+      sdist_filename: ${{ steps.generate.outputs.filename }}
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - uses: actions/setup-python@v4
+      with:
+        python-version: 3.11
+
+    - name: Install Build Command
+      run: python -m pip install build
+
+    - name: Generate Sdist
+      id: generate
+      run: |
+        python -m build -s . --outdir dist
+        echo "filename=$(ls dist)" >> "$GITHUB_OUTPUT"
+
+    - name: Upload Sdist
+      uses: actions/upload-artifact@v3
+      with:
+        name: sdist
+        path: ./dist/*.tar.gz
+
+  # Create the wheels. It'll use the sdist to confirm that we can compile MaterialX from the sdist.
+  # https://packaging.python.org/en/latest/flow#the-built-distributions-wheels
+  wheels:
+    name: Generate Wheel
+    runs-on: ${{ matrix.os }}
+    needs: ['sdist']
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ['37', '38', '39', '310', '311']
+        os: ['ubuntu-latest', 'macos-latest', 'windows-latest']
+
+    steps:
+    - name: Download Sdist
+      uses: actions/download-artifact@v3
+      with:
+        name: sdist
+        path: sdist
+
+    - name: Build Wheel
+      # https://cibuildwheel.readthedocs.io/en/stable/
+      uses: pypa/[email protected]
+      with:
+        # Build from the sdist. We want to make sure it's valid and works as expected.
+        package-dir: ${{ github.workspace }}/sdist/${{ needs.sdist.outputs.sdist_filename }}
+        output-dir: wheels
+      env:
+        CIBW_BUILD: 'cp${{ matrix.python-version }}-*'
+        CIBW_SKIP: '*musllinux*'
+        CIBW_ARCHS: 'auto64'
+        # https://github.com/pypa/manylinux
+        # manylinux2014 is CentOS 7 based. Which means GCC 10 and glibc 2.17.
+        CIBW_MANYLINUX_X86_64_IMAGE: manylinux2014
+        CIBW_BEFORE_ALL_LINUX: yum install -y libXt-devel
+        CIBW_BEFORE_ALL_MACOS: sudo xcode-select -switch /Applications/Xcode_13.4.app
+        CIBW_BUILD_VERBOSITY: 1
+        CIBW_ENVIRONMENT: CMAKE_BUILD_PARALLEL_LEVEL=2
+        # CIBW_BUILD_FRONTEND: build  # https://github.com/pypa/build
+        MACOSX_DEPLOYMENT_TARGET: '10.15'
+
+    - name: Upload Wheel
+      uses: actions/upload-artifact@v3
+      with:
+        name: wheels
+        path: ./wheels/*.whl
+
+  test:
+    name: Test Wheel
+    needs: ['wheels']
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ['3.7', '3.8', '3.9', '3.10', '3.11']
+        os: ['ubuntu-latest', 'macos-latest', 'windows-latest']
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - uses: actions/setup-python@v4
+      with:
+        python-version: ${{ matrix.python-version }}
+
+    - name: Download Wheels
+      uses: actions/download-artifact@v3
+      with:
+        name: wheels
+        path: wheels
+
+    - name: Install Wheel
+      run: python -m pip install MaterialX --find-links wheels --no-index
+
+    - name: Python Tests
+      shell: bash
+      run: |
+        set -e
+        python python/MaterialXTest/main.py
+        python python/MaterialXTest/genshader.py
+        python python/Scripts/mxformat.py ./resources/Materials/TestSuite/stdlib/upgrade --yes --upgrade
+        python python/Scripts/mxvalidate.py ./resources/Materials/Examples/StandardSurface/standard_surface_marble_solid.mtlx --stdlib --verbose
+        python python/Scripts/mxdoc.py --docType md ./libraries/pbrlib/pbrlib_defs.mtlx
+        python python/Scripts/mxdoc.py --docType html ./libraries/bxdf/standard_surface.mtlx
+        python python/Scripts/generateshader.py ./resources/Materials/Examples/StandardSurface --target glsl
+        python python/Scripts/generateshader.py ./resources/Materials/Examples/StandardSurface --target osl
+        python python/Scripts/generateshader.py ./resources/Materials/Examples/StandardSurface --target mdl
+        python python/Scripts/generateshader.py ./resources/Materials/Examples/StandardSurface --target msl

.gitignore

@@ -1 +1,2 @@
 build
+dist

CMakeLists.txt

@@ -31,7 +31,7 @@ if (MATERIALX_BUILD_JS)
     endif()
 endif()
 
-project(MaterialX)
+project(MaterialX VERSION ${MATERIALX_LIBRARY_VERSION})
 
 option(MATERIALX_BUILD_PYTHON "Build the MaterialX Python package from C++ bindings. Requires Python 3.6 or greater." OFF)
 option(MATERIALX_BUILD_VIEWER "Build the MaterialX Viewer." OFF)
@@ -101,6 +101,12 @@ set(MATERIALX_OSL_BINARY_OSLC "" CACHE FILEPATH "Full path to the OSL compiler b
 set(MATERIALX_OSL_BINARY_TESTRENDER "" CACHE FILEPATH "Full path to the OSL test render binary.")
 set(MATERIALX_OSL_INCLUDE_PATH "" CACHE PATH "Full path to OSL shader includes (e.g. 'stdosl.h').")
 
+set(MATERIALX_PYTHON_FOLDER_NAME "python/MaterialX" CACHE INTERNAL "Folder name to user for installing the Python library.")
+
+if(SKBUILD)
+    set(MATERIALX_PYTHON_FOLDER_NAME "MaterialX")
+endif()
+
 # Helpers for MDL validation
 if (MATERIALX_BUILD_GEN_MDL)
     set(MATERIALX_MDLC_EXECUTABLE "" CACHE FILEPATH "Full path to the mdlc binary.")
@@ -207,6 +213,12 @@ set(MATERIALX_SAME_DIR_RPATH "${RPATH_RELATIVE_SYMBOL};${CMAKE_INSTALL_PREFIX}/$
 set(MATERIALX_UP_ONE_RPATH "${RPATH_RELATIVE_SYMBOL}/../${MATERIALX_INSTALL_LIB_PATH};${MATERIALX_SAME_DIR_RPATH}")
 # For linking to libraries where source is two directories deep, ie: "MATX/python/MaterialX/../../lib"
 set(MATERIALX_UP_TWO_RPATH "${RPATH_RELATIVE_SYMBOL}/../../${MATERIALX_INSTALL_LIB_PATH};${MATERIALX_SAME_DIR_RPATH}")
+if(SKBUILD)
+    # When building the Python wheels, we don't want to set any RPATH because
+    # we want to wheel to be self-contained. We don't want any interference from
+    # external paths.
+    set(MATERIALX_UP_TWO_RPATH "${RPATH_RELATIVE_SYMBOL}")
+endif()
 
 # Adjust compiler settings
 if(MSVC)
@@ -300,7 +312,7 @@ if(MATERIALX_BUILD_RENDER)
     if(MATERIALX_BUILD_GRAPH_EDITOR)
         add_subdirectory(source/MaterialXGraphEditor)
     endif()
-    if(MATERIALX_INSTALL_RESOURCES)
+    if(MATERIALX_INSTALL_RESOURCES AND NOT SKBUILD)
         add_subdirectory(resources)
     endif()
 endif()
@@ -335,26 +347,28 @@ if(${CMAKE_VERSION} VERSION_GREATER "3.6.2")
 endif()
 
 # Install root-level documents
-install(FILES LICENSE CHANGELOG.md README.md THIRD-PARTY.md
-        DESTINATION .)
-
-set(MATERIALX_GEN_CONFIG_PATH "${MATERIALX_INSTALL_LIB_PATH}/cmake/${CMAKE_PROJECT_NAME}")
-
-include(CMakePackageConfigHelpers)
-configure_package_config_file(cmake/modules/MaterialXConfig.cmake.in
-                              ${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}Config.cmake
-                              INSTALL_DESTINATION "${MATERIALX_GEN_CONFIG_PATH}"
-                              PATH_VARS CMAKE_INSTALL_PREFIX CMAKE_PROJECT_NAME)
-write_basic_package_version_file(${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}ConfigVersion.cmake
-                                 VERSION ${MATERIALX_LIBRARY_VERSION}
-                                 COMPATIBILITY AnyNewerVersion)
-
-# Install the auto-generated CMake configuration files:
-
-install(EXPORT MaterialX
-        DESTINATION "${MATERIALX_GEN_CONFIG_PATH}"
-        FILE ${CMAKE_PROJECT_NAME}Targets.cmake)
-
-install(FILES "${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}ConfigVersion.cmake"
-        "${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}Config.cmake"
-        DESTINATION "${MATERIALX_GEN_CONFIG_PATH}")
+if(NOT SKBUILD)
+    install(FILES LICENSE CHANGELOG.md README.md THIRD-PARTY.md
+            DESTINATION .)
+
+    set(MATERIALX_GEN_CONFIG_PATH "${MATERIALX_INSTALL_LIB_PATH}/cmake/${CMAKE_PROJECT_NAME}")
+
+    include(CMakePackageConfigHelpers)
+    configure_package_config_file(cmake/modules/MaterialXConfig.cmake.in
+                                ${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}Config.cmake
+                                INSTALL_DESTINATION "${MATERIALX_GEN_CONFIG_PATH}"
+                                PATH_VARS CMAKE_INSTALL_PREFIX CMAKE_PROJECT_NAME)
+    write_basic_package_version_file(${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}ConfigVersion.cmake
+                                    VERSION ${MATERIALX_LIBRARY_VERSION}
+                                    COMPATIBILITY AnyNewerVersion)
+
+    # Install the auto-generated CMake configuration files:
+
+    install(EXPORT MaterialX
+            DESTINATION "${MATERIALX_GEN_CONFIG_PATH}"
+            FILE ${CMAKE_PROJECT_NAME}Targets.cmake)
+
+    install(FILES "${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}ConfigVersion.cmake"
+            "${CMAKE_BINARY_DIR}/cmake/${CMAKE_PROJECT_NAME}Config.cmake"
+            DESTINATION "${MATERIALX_GEN_CONFIG_PATH}")
+endif()

libraries/CMakeLists.txt

@@ -1,20 +1,26 @@
-install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/
-        DESTINATION "${MATERIALX_INSTALL_STDLIB_PATH}" MESSAGE_NEVER
-        PATTERN "CMakeLists.txt" EXCLUDE
-        PATTERN "pbrlib_genosl_impl.*" EXCLUDE)
-
 if (MATERIALX_OSL_LEGACY_CLOSURES)
     set(PBRLIB_SUFFIX "legacy")
 else()
     set(PBRLIB_SUFFIX "mtlx")
 endif()
 
-install(FILES "${CMAKE_CURRENT_SOURCE_DIR}/pbrlib/genosl/pbrlib_genosl_impl.${PBRLIB_SUFFIX}"
-        DESTINATION "${MATERIALX_INSTALL_STDLIB_PATH}/pbrlib/genosl/" RENAME pbrlib_genosl_impl.mtlx)
+if(NOT SKBUILD)
+    install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/
+            DESTINATION "${MATERIALX_INSTALL_STDLIB_PATH}"
+            PATTERN "CMakeLists.txt" EXCLUDE
+            PATTERN "pbrlib_genosl_impl.*" EXCLUDE)
+    install(FILES "${CMAKE_CURRENT_SOURCE_DIR}/pbrlib/genosl/pbrlib_genosl_impl.${PBRLIB_SUFFIX}"
+            DESTINATION "${MATERIALX_INSTALL_STDLIB_PATH}/pbrlib/genosl/" RENAME pbrlib_genosl_impl.mtlx)
+endif()
+
+set(MATERIALX_PYTHON_LIBRARIES_PATH "${MATERIALX_PYTHON_FOLDER_NAME}/${MATERIALX_INSTALL_STDLIB_PATH}")
+if(SKBUILD)
+    set(MATERIALX_PYTHON_LIBRARIES_PATH "${SKBUILD_PLATLIB_DIR}/MaterialX/libraries")
+endif()
 
 install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/
-        DESTINATION "python/MaterialX/${MATERIALX_INSTALL_STDLIB_PATH}" 
+        DESTINATION "${MATERIALX_PYTHON_LIBRARIES_PATH}"
         PATTERN "CMakeLists.txt" EXCLUDE
         PATTERN "pbrlib_genosl_impl.*" EXCLUDE)
 install(FILES "${CMAKE_CURRENT_SOURCE_DIR}/pbrlib/genosl/pbrlib_genosl_impl.${PBRLIB_SUFFIX}"
-        DESTINATION "python/MaterialX/${MATERIALX_INSTALL_STDLIB_PATH}/pbrlib/genosl/" RENAME pbrlib_genosl_impl.mtlx)
+        DESTINATION "${MATERIALX_PYTHON_LIBRARIES_PATH}/pbrlib/genosl/" RENAME pbrlib_genosl_impl.mtlx)

pyproject.toml

@@ -0,0 +1,78 @@
+[build-system]
+# Use a fixed version because we use an experimental feature
+# (a custom plugin) and for now that functionality has
+# no compatibility promises.
+requires = ["scikit-build-core==0.4.4"]
+build-backend = "scikit_build_core.build"
+
+[project]
+name = "MaterialX"
+dynamic = ["version"]
+
+authors = [
+  { name="Contributors to the MaterialX project", email="[email protected]" },
+]
+readme = "README.md"
+requires-python = ">=3.6"
+
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: Apache Software License",
+    "Operating System :: OS Independent",
+]
+
+[project.urls]
+"Homepage" = "https://materialx.org"
+"Source" = "https://github.com/AcademySoftwareFoundation/MaterialX"
+"Bug Tracker" = "https://github.com/AcademySoftwareFoundation/MaterialX/issues"
+
+[project.scripts]
+baketextures = "MaterialX._scripts.baketextures:main"
+generateshader = "MaterialX._scripts.generateshader:main"
+genmdl = "MaterialX._scripts.genmdl:main"
+mxdoc = "MaterialX._scripts.mxdoc:main"
+mxupdate = "MaterialX._scripts.mxupdate:main"
+mxvalidate = "MaterialX._scripts.mxvalidate:main"
+translateshader = "MaterialX._scripts.translateshader:main"
+writenodegraphs = "MaterialX._scripts.writenodegraphs:main"
+
+[tool.scikit-build]
+cmake.minimum-version = "3.18"
+cmake.verbose = false
+cmake.build-type = "Release"
+
+# Enable experimental features if any are available
+# In this case we need custom local plugin to get
+# the project version from cmake.
+experimental = true
+metadata.version.provider = "mtx_skbuild_plugin"
+metadata.version.provider-path = "./python"
+
+# Uncoment when developing locally to enable inplace builds.
+# build-dir = "build/"
+
+logging.level = "DEBUG"
+
+# Since the python package doesn't live in a standard directory
+# in the source (i.e ./src or ./), we need to manually specify
+# where the package is.
+wheel.packages = ["python/MaterialX"]
+
+sdist.exclude = [
+    "/build",
+    "/dist",
+    "/resources",
+    "/javascript",
+    "/documents",
+    "/.github",
+    "MANIFEST.in"
+]
+
+[tool.scikit-build.cmake.define]
+MATERIALX_BUILD_SHARED_LIBS = 'OFF' # Be explicit
+MATERIALX_BUILD_PYTHON = 'ON'
+MATERIALX_TEST_RENDER = 'OFF'
+MATERIALX_WARNINGS_AS_ERRORS = 'ON'
+MATERIALX_BUILD_TESTS = 'OFF'
+# TODO: How could we harmonize this variable with SKBUILD?
+MATERIALX_INSTALL_PYTHON = 'OFF'

python/CMakeLists.txt

@@ -1,18 +1,25 @@
-set(SETUP_PY_IN "${CMAKE_CURRENT_SOURCE_DIR}/setup.py.in")
-set(SETUP_PY "${CMAKE_INSTALL_PREFIX}/python/setup.py")
-
-configure_file(${SETUP_PY_IN} ${SETUP_PY})
+if(NOT SKBUILD)
+  install(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/MaterialX" DESTINATION "python" MESSAGE_NEVER)
+  install(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/Scripts" DESTINATION "python" MESSAGE_NEVER)
+endif()
 
-install(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/MaterialX" DESTINATION "python" MESSAGE_NEVER)
-install(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/Scripts" DESTINATION "python" MESSAGE_NEVER)
+if(SKBUILD)
+  install(
+    DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/Scripts/"
+    DESTINATION "${MATERIALX_PYTHON_FOLDER_NAME}/_scripts"
+    PATTERN "README.md" EXCLUDE
+  )
+endif()
 
 if(MATERIALX_PYTHON_OCIO_DIR)
   if(NOT EXISTS "${MATERIALX_PYTHON_OCIO_DIR}/config.ocio")
     message(WARNING "No file named config.ocio was found in the given OCIO directory.")
   endif()
-  install(DIRECTORY "${MATERIALX_PYTHON_OCIO_DIR}/" DESTINATION "python/MaterialX/config/" MESSAGE_NEVER)
+  install(DIRECTORY "${MATERIALX_PYTHON_OCIO_DIR}/" DESTINATION "${MATERIALX_PYTHON_FOLDER_NAME}/config/" MESSAGE_NEVER)
 endif()
 
-if(MATERIALX_INSTALL_PYTHON AND PYTHON_EXECUTABLE)
-  install(CODE "execute_process(COMMAND ${PYTHON_EXECUTABLE} ${SETUP_PY} install clean --all)" MESSAGE_NEVER)
+if(MATERIALX_INSTALL_PYTHON AND PYTHON_EXECUTABLE AND NOT SKBUILD)
+  set(SETUP_PY "${CMAKE_INSTALL_PREFIX}/python/setup.py")
+  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/setup.py.in" "${SETUP_PY}")
+  install(CODE "execute_process(COMMAND ${PYTHON_EXECUTABLE} ${SETUP_PY} install clean --all)")
 endif()

python/MaterialX/_scripts/README.md

@@ -0,0 +1,2 @@
+This directory is empty buit it's used when packaging the Python library.
+the files in ../../Scripts will be copied inside.

python/MaterialX/_scripts/__init__.py

@@ -0,0 +1 @@
+# Only required for entry-points.