build(deps): add yaml-cpp build recipe

It's an OCIO dependency.

src/cmake/build_yaml-cpp.cmake

@@ -0,0 +1,41 @@
+# Copyright Contributors to the OpenImageIO project.
+# SPDX-License-Identifier: Apache-2.0
+# https://github.com/AcademySoftwareFoundation/OpenImageIO
+
+######################################################################
+# yaml-cpp by hand!
+######################################################################
+
+set_cache (yaml-cpp_BUILD_VERSION 0.8.0 "yaml-cpp version for local builds")
+set (yaml-cpp_GIT_REPOSITORY "https://github.com/jbeder/yaml-cpp")
+set (yaml-cpp_GIT_TAG "${yaml-cpp_BUILD_VERSION}") # NB: versions earlier than 0.8.0 had a "yaml-cpp-" prefix
+
+set_cache (yaml-cpp_BUILD_SHARED_LIBS ${LOCAL_BUILD_SHARED_LIBS_DEFAULT}
+           DOC "Should a local yaml-cpp build, if necessary, build shared libraries" ADVANCED)
+
+string (MAKE_C_IDENTIFIER ${yaml-cpp_BUILD_VERSION} yaml-cpp_VERSION_IDENT)
+
+build_dependency_with_cmake(yaml-cpp
+    VERSION         ${yaml-cpp_BUILD_VERSION}
+    GIT_REPOSITORY  ${yaml-cpp_GIT_REPOSITORY}
+    GIT_TAG         ${yaml-cpp_GIT_TAG}
+    CMAKE_ARGS
+        -D YAML_CPP_BUILD_TESTS=OFF
+        -D YAML_CPP_BUILD_TOOLS=OFF
+        -D YAML_CPP_BUILD_CONTRIB=OFF
+        -D YAML_BUILD_SHARED_LIBS=${yaml-cpp_BUILD_SHARED_LIBS}
+        -D CMAKE_INSTALL_LIBDIR=lib
+    )
+
+set (yaml-cpp_ROOT ${yaml-cpp_LOCAL_INSTALL_DIR})
+set (yaml-cpp_DIR ${yaml-cpp_LOCAL_INSTALL_DIR})
+set (yaml-cpp_VERSION ${yaml-cpp_BUILD_VERSION})
+
+set (yaml-cpp_REFIND TRUE)
+set (yaml-cpp_REFIND_ARGS CONFIG)
+set (yaml-cpp_REFIND_VERSION ${yaml-cpp_BUILD_VERSION})
+
+
+if (yaml-cpp_BUILD_SHARED_LIBS)
+    install_local_dependency_libs (yaml-cpp yaml-cpp)
+endif ()

src/cmake/externalpackages.cmake

@@ -129,8 +129,12 @@ checked_find_package (Freetype
                       VERSION_MIN 2.10.0
                       DEFINITIONS USE_FREETYPE=1 )
 
-checked_find_package (OpenColorIO
-                      VERSION_MIN 1.1
+
+checked_find_package (yaml-cpp
+                      VERSION_MIN 0.6.0 )  # Used by OpenColorIO
+
+checked_find_package (OpenColorIO REQUIRED
+                      VERSION_MIN 2.2
                       VERSION_MAX 2.9
                       NO_FP_RANGE_CHECK
                       DEFINITIONS  USE_OCIO=1 USE_OPENCOLORIO=1