Add SlangConfig.cmake with slang build targets (#5674)

* Modify package config

* Apply formatting.

* Make sure build works for Emscripten

* Add documentation on install target.

---------

Co-authored-by: obhi-d <obi.de.online@gmail.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index dc281211e..5a53ba731 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -338,3 +338,43 @@ install(DIRECTORY "${slang_SOURCE_DIR}/docs/" DESTINATION share/doc/slang)
 install(DIRECTORY "${slang_SOURCE_DIR}/include" DESTINATION .)
 
 include(CPack)
+
+# Write basic package config version file using standard CMakePackageConfigHelpers utility
+include(CMakePackageConfigHelpers)
+write_basic_package_version_file(
+    "${PROJECT_NAME}ConfigVersion.cmake"
+    VERSION ${PROJECT_VERSION}
+    COMPATIBILITY SameMajorVersion
+)
+
+# Write SlangConfig.cmake which should allow find_pacakage(SLANG) to work correctly
+# SlangConfig.cmake will define slang::slang target that can be linked with using
+# target_link_libraries. It will also define SLANG_EXECUTABLE export variable that
+# should point to slangc if SLANG_ENABLE_SLANGC is ON.
+configure_package_config_file(
+    "${PROJECT_SOURCE_DIR}/cmake/SlangConfig.cmake.in"
+    "${PROJECT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
+    INSTALL_DESTINATION cmake
+)
+
+# Conditionally handle the case for Emscripten where slang does not create linkable
+# targets. In this case do not export the targets. Otherwise, just export the 
+# slang target, as this is the library that is required to use the compiler. This possibly
+# should later be expanded to include slang-rhi targets if some program intends to use them, 
+# but possibly wait for a future request before expanding this export set.
+if(NOT CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+    install(TARGETS slang EXPORT SlangExportTarget)
+    install(
+        EXPORT SlangExportTarget
+        FILE ${PROJECT_NAME}Targets.cmake
+        NAMESPACE ${PROJECT_NAME}::
+        DESTINATION cmake
+    )
+endif()
+
+install(
+    FILES
+        "${PROJECT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
+        "${PROJECT_BINARY_DIR}/${PROJECT_NAME}ConfigVersion.cmake"
+    DESTINATION cmake
+)