From 4b8a3cbb06362672cbced8ba136b0b31f9100b92 Mon Sep 17 00:00:00 2001
From: "M. Eric Irrgang" <vardarirrgan1@llnl.gov>
Date: Fri, 8 Aug 2025 14:51:49 -0700
Subject: [PATCH] Support Python wheel packaging.

- Update CMake infrastructure.
- Update Python source layout.
- Add pyproject.toml.
- Add additional instructions.

Deferred:
- Editable installs are not yet supported because of the way the Python code calls `ctypes`.
---
 CMakeLists.txt                                |  4 +-
 README.md                                     | 20 +++++++++-
 pyproject.toml                                | 40 +++++++++++++++++++
 src/CMakeLists.txt                            | 13 ++----
 .../__init__.py}                              |  2 +-
 5 files changed, 65 insertions(+), 14 deletions(-)
 create mode 100644 pyproject.toml
 rename src/{xrayphysics.py => xrayphysics/__init__.py} (99%)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e922031..397630a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
-cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.20 FATAL_ERROR)
 
-project(xrayphysics)
+project(xrayphysics CXX)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
diff --git a/README.md b/README.md
index f61d407..eb32266 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,25 @@ The x-ray source models are at least as accurate as TASMICS and much more flexib
 
 ## Installation and Usage
 
+A python *wheel* package can be built and installed as follows.
+
+```commandline
+python -m pip install --upgrade pip build
+python -m build .
+pip install dist/xrayphysics*whl
+```
+
+The wildcard `*` is used in the above example because the exact package file name may vary.
+
+If the build system cannot find all dependencies, they can be provided with CMake variables.
+For example,
+
+```commandline
+python -m build . \
+    -Ccmake.define.CMAKE_PREFIX_PATH=/opt/homebrew \
+    -Ccmake.define.OpenMP_ROOT=/opt/homebrew/opt/libomp
+```
+
 Documentation is available [here](https://xrayphysics.readthedocs.io/)
 
 Installation and usage information is posted on the [wiki page](https://github.com/kylechampley/XrayPhysics/wiki)
@@ -40,4 +59,3 @@ Champley, Kyle M., Stephen G. Azevedo, Isaac M. Seetho, Steven M. Glenn, Larry D
 Kyle Champley and Timo Bremer. ”Efficient and Accurate Correction of
 Beam Hardening Artifacts.”, 3rd International Congress on Image Formation
 in X-ray CT, 2014.
-
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..4cffa3d
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,40 @@
+[build-system]
+requires = ["scikit-build-core"]
+build-backend = "scikit_build_core.build"
+
+[project]
+name = "xrayphysics"
+authors = [
+    { name = "Kyle Champley", email = "champley@gmail.com" },
+]
+description = "x-ray cross section tables, x-ray tube source simulation, beam hardening correction, and dual energy decompositon"
+readme = "README.md"
+requires-python = ">=3.6"
+#license = { text = "internal use only" }
+dependencies = [
+    "numpy",
+]
+version = "1.2"
+
+[project.optional-dependencies]
+
+[tool.scikit-build]
+
+# Extra args to pass directly to the builder in the build step.
+build.tool-args = []
+
+# The build targets to use when building the project. Empty builds the default
+# target.
+build.targets = []
+
+# The components to install. If empty, all default components are installed.
+install.components = []
+
+sdist.cmake = true
+sdist.include = [
+    "LICENSE",
+]
+
+wheel.packages = ["src/xrayphysics"]
+wheel.license-files = ["LICENSE.txt"]
+wheel.py-api = "py3"
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index ed9df05..163df9b 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,10 +1,3 @@
-cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
-
-project(xrayphysics CXX)
-
-set(CMAKE_CXX_STANDARD 17)
-set(CMAKE_CXX_STANDARD_REQUIRED ON)
-
 find_package(OpenMP REQUIRED)
 
 if (WIN32)
@@ -62,7 +55,7 @@ target_link_libraries(${PROJECT_NAME}
 
 install(TARGETS ${PROJECT_NAME}
   PUBLIC_HEADER DESTINATION include
-  RUNTIME DESTINATION bin
-  ARCHIVE DESTINATION lib
-  LIBRARY DESTINATION lib
+  RUNTIME DESTINATION xrayphysics
+  ARCHIVE DESTINATION xrayphysics
+  LIBRARY DESTINATION xrayphysics
 )
diff --git a/src/xrayphysics.py b/src/xrayphysics/__init__.py
similarity index 99%
rename from src/xrayphysics.py
rename to src/xrayphysics/__init__.py
index 3cc4143..6dc60d6 100644
--- a/src/xrayphysics.py
+++ b/src/xrayphysics/__init__.py
@@ -160,7 +160,7 @@ def resample(self, gammas, s, gammas_out):
         Args:
             gammas (numpy array): the energy samples (keV) of the given spectra
             s (numpy array): the given spectra to resample
-            gammmas_out (numpy array): the energy samples (keV) to rebin to
+            gammas_out (numpy array): the energy samples (keV) to rebin to
         
         Returns:
             resampled spectra