ci: As a favor to OpenEXR, test their experimental core library changes

Signed-off-by: Larry Gritz <[email protected]>

.github/workflows/ci.yml

@@ -207,6 +207,19 @@ jobs:
             setenvs: export OIIO_CMAKE_FLAGS="-DOIIO_BUILD_TOOLS=0 -DOIIO_BUILD_TESTS=0 -DUSE_PYTHON=0"
                             USE_OPENCV=0 USE_FFMPEG=0 USE_PYTHON=0 USE_FREETYPE=0
                             CMAKE_BUILD_TYPE=RelWithDebInfo
+          # Special temporary test to exercise OpenEXR's experimental branch
+          # with Kimball's reworking of the C++API to use the EXRCore library.
+          - desc: exr-core-rewrite gcc11/C++17 py3.11 exr3.2 ocio2.3
+            nametag: exr-core-rewrite
+            runner: ubuntu-latest
+            container: aswftesting/ci-osl:2024-clang17
+            vfxyear: 2024
+            cxx_std: 17
+            python_ver: "3.11"
+            simd: "avx2,f16c"
+            pybind11_ver: v2.10.0
+            openexr_ver: staging/cpp_core_rewrite
+            setenvs: export USE_OPENCV=0 USE_FFMPEG=0 USE_OPENVDB=0
 
     runs-on: ${{ matrix.runner }}
     container:

src/libOpenImageIO/CMakeLists.txt

@@ -106,6 +106,11 @@ endif ()
 # Enable default use of OpenEXR core library for versions of the library
 # new enough to support DWA compression in exrcore.
 if (OPENEXR_VERSION VERSION_GREATER_EQUAL 3.1.10)
+    set_option (OIIO_OPENEXR_CORE_DEFAULT "Use OpenEXR core library by default" ON)
+else ()
+    set_option (OIIO_OPENEXR_CORE_DEFAULT "Use OpenEXR core library by default" OFF)
+endif ()
+if (OIIO_OPENEXR_CORE_DEFAULT)
     target_compile_definitions(OpenImageIO
                                PRIVATE OIIO_OPENEXR_CORE_DEFAULT=1)
     message (STATUS "OpenEXR core library will be used by default")