cmake script to auto download and install the openjpeg dependency

.github/workflows/ci.yml

@@ -544,7 +544,6 @@ jobs:
             setenvs: export OpenImageIO_BUILD_LOCAL_DEPS=all
                             OpenImageIO_DEPENDENCY_BUILD_VERBOSE=ON
                             LIBRAW_VERSION=0.21.4
-                            OPENJPEG_VERSION=v2.5.4
                             PTEX_VERSION=v2.4.2
                             PUGIXML_VERSION=v1.14
                             WEBP_VERSION=v1.4.0

src/cmake/build_OpenJPEG.cmake

@@ -0,0 +1,32 @@
+# Copyright Contributors to the OpenImageIO project.
+# SPDX-License-Identifier: Apache-2.0
+# https://github.com/Academ SoftwareFoundation/OpenImageIO
+
+set_cache (OpenJPEG_BUILD_VERSION 2.5.4 "OpenJPEG version for local builds")
+set (OpenJPEG_GIT_REPOSITORY "https://github.com/uclouvain/openjpeg.git")
+set (OpenJPEG_GIT_TAG "v${OpenJPEG_BUILD_VERSION}")
+set_cache (OpenJPEG_BUILD_SHARED_LIBS ${LOCAL_BUILD_SHARED_LIBS_DEFAULT}
+           DOC "Should a local OpenJPEG build, if necessary, build shared libraries" ADVANCED)
+
+
+string (MAKE_C_IDENTIFIER ${OpenJPEG_BUILD_VERSION} OpenJPEG_VERSION_IDENT)
+
+build_dependency_with_cmake(OpenJPEG
+    VERSION         ${OpenJPEG_BUILD_VERSION}
+    GIT_REPOSITORY  ${OpenJPEG_GIT_REPOSITORY}
+    GIT_TAG         ${OpenJPEG_GIT_TAG}
+    CMAKE_ARGS
+        -D BUILD_CODEC=OFF 
+        -D CMAKE_POSITION_INDEPENDENT_CODE=ON
+    )
+# Set some things up that we'll need for a subsequent find_package to work
+set (OpenJPEG_ROOT ${OpenJPEG_LOCAL_INSTALL_DIR})
+
+
+# Signal to caller that we need to find again at the installed location
+set (OpenJPEG_REFIND TRUE)
+set (OpenJPEG_REFIND_ARGS CONFIG)
+
+if (OpenJPEG_BUILD_SHARED_LIBS)
+    install_local_dependency_libs (OpenJPEG openjp2)
+endif ()

src/cmake/externalpackages.cmake

@@ -172,7 +172,8 @@ checked_find_package (LibRaw
 
 checked_find_package (OpenJPEG VERSION_MIN 2.0
                       RECOMMEND_MIN 2.2
-                      RECOMMEND_MIN_REASON "for multithreading support")
+                      RECOMMEND_MIN_REASON "for multithreading support"
+                      PREFER_CONFIG)
 # Note: Recent OpenJPEG versions have exported cmake configs, but we don't
 # find them reliable at all, so we stick to our FindOpenJPEG.cmake module.
 

src/cmake/modules/FindOpenJPEG.cmake

@@ -174,6 +174,15 @@ if (OPENJPEG_FOUND)
   foreach (tmplib ${OpenJpeg_libvars})
     list (APPEND OPENJPEG_LIBRARIES ${${tmplib}})
   endforeach ()
+
+  if (NOT TARGET openjp2)
+      add_library(openjp2 UNKNOWN IMPORTED)
+      set_target_properties(openjp2 PROPERTIES
+          INTERFACE_INCLUDE_DIRECTORIES "${OPENJPEG_INCLUDES}")
+      set_property(TARGET openjp2 APPEND PROPERTY
+                   IMPORTED_LOCATION "${OPENJPEG_LIBRARIES}")
+  endif()
+
   if (NOT OpenJpeg_FIND_QUIETLY)
     FIND_PACKAGE_MESSAGE (OPENJPEG
       "Found OpenJpeg: v${OPENJPEG_VERSION} ${OPENJPEG_LIBRARIES}"

src/jpeg2000.imageio/CMakeLists.txt

@@ -3,9 +3,17 @@
 # https://github.com/AcademySoftwareFoundation/OpenImageIO
 
 if (OPENJPEG_FOUND)
-    set(_jpeg2000_includes ${OPENJPEG_INCLUDES})
-    set(_jpeg2000_lib_dirs ${OPENJPEG_LIBRARY_DIRS})
-    set(_jpeg2000_libs ${OPENJPEG_LIBRARIES})
+    if (TARGET openjp2_static AND (LINKSTATIC OR NOT TARGET openjp2))
+        # Use static OpenJPEG library for LINKSTATIC situations, or if
+        # no dynamic library is available.
+        set (OPENJPEG_TARGET openjp2_static)
+    elseif (TARGET openjp2)
+        set (OPENJPEG_TARGET openjp2)
+    else ()
+        set(_jpeg2000_includes ${OPENJPEG_INCLUDES})
+        set(_jpeg2000_lib_dirs ${OPENJPEG_LIBRARY_DIRS})
+        set(_jpeg2000_libs ${OPENJPEG_LIBRARIES})
+    endif ()
     set(_jpeg2000_defs "USE_OPENJPEG")
 
     if (openjph_FOUND)
@@ -16,6 +24,7 @@ if (OPENJPEG_FOUND)
         INCLUDE_DIRS ${_jpeg2000_includes}
         LINK_DIRECTORIES ${_jpeg2000_lib_dirs}
         LINK_LIBRARIES ${_jpeg2000_libs}
+                       ${OPENJPEG_TARGET}
                        $<TARGET_NAME_IF_EXISTS:openjph>
         DEFINITIONS ${_jpeg2000_defs}
     )