Fix for external Imath, must set USE_DEPS_IMATH OFF (#1273)

* Make the Imath detection logic much easier to understand and use
Co-authored-by: Nick Porcino <nporcino@pixar.com>

Author: 2 people

CMakeLists.txt

@@ -31,7 +31,8 @@ option(OTIO_DEPENDENCIES_INSTALL      "Install OTIO's C++ header dependencies (a
 option(OTIO_INSTALL_PYTHON_MODULES    "Install OTIO pure Python modules/files" ON)
 option(OTIO_INSTALL_COMMANDLINE_TOOLS "Install the OTIO command line tools" ON)
 option(OTIO_INSTALL_CONTRIB           "Install the opentimelineio_contrib Python package" ON)
-option(OTIO_FIND_IMATH                "Find Imath in the environment" OFF)
+set(OTIO_IMATH_LIBS "" CACHE STRING   "Imath library overrides to use instead of src/deps or find_package")
+option(OTIO_FIND_IMATH                "Find Imath using find_package, ignored if OTIO_IMATH_LIBS is set" OFF)
 set(OTIO_PYTHON_INSTALL_DIR "" CACHE STRING "Python installation dir (such as the site-packages dir)")
 
 # Build options
@@ -231,23 +232,30 @@ set(CTEST_OUTPUT_ON_FAILURE ON)
 # Build the dependencies and components
 
 #----- Imath
-# prefer an installed Imath 3.
-if (OTIO_FIND_IMATH)
+set(OTIO_RESOLVED_IMATH_LIBRARIES "")
+if (NOT "${OTIO_IMATH_LIBS}" STREQUAL "")
+    message(STATUS "Using Imath from OTIO_MATH_LIBS: ${OTIO_IMATH_LIBS}")
+    set(OTIO_RESOLVED_IMATH_LIBRARIES "${OTIO_IMATH_LIBS}")
+    set(USE_DEPS_IMATH OFF)
+elseif(OTIO_FIND_IMATH)
     find_package(Imath QUIET)
-    if (NOT Imath_FOUND)
-        # check if there is an installed IlmBase
+    if (Imath_FOUND)
+        message(STATUS "Found Imath 3 at ${Imath_CONFIG}")
+        set(USE_DEPS_IMATH OFF)
+    else()
         find_package(IlmBase QUIET)
-        if (NOT IlmBase_FOUND)
-            message(STATUS "Using Imath in OpenTimelineIO/src/deps")
-            set(USE_DEPS_IMATH ON)
+        if (IlmBase_FOUND)
+            message(STATUS "Imath 3 not found, found Imath 2 at ${IlmBase_CONFIG}")
+            message(STATUS "You may need to point to the Imath headers by setting IMATH_INCLUDES")
+            set(USE_DEPS_IMATH_OFF)
+            set(OTIO_RESOLVED_IMATH_LIBRARIES "${IlmBase_LIBRARIES")
         else()
-            message(STATUS "Using IlmBase::Imath specifed by ${IlmBase_CONFIG}")
+            message(STATUS "Imath 3 and 2 were not found, using src/deps/Imath")
+            set(USE_DEPS_IMATH ON)
         endif()
-    else()
-        message(STATUS "Using Imath::Imath specified by ${Imath_CONFIG}")
     endif()
 else()
-    message(STATUS "Using Imath in OpenTimelineIO/src/deps")
+    message(STATUS "Using src/deps/Imath by default")
     set(USE_DEPS_IMATH ON)
 endif()
 

src/opentimelineio/CMakeLists.txt

@@ -40,50 +40,52 @@ set(OPENTIMELINEIO_HEADER_FILES
     version.h)
 
 add_library(opentimelineio ${OTIO_SHARED_OR_STATIC_LIB} 
-            clip.cpp
-            composable.cpp
-            composition.cpp
-            deserialization.cpp
-            effect.cpp
-            errorStatus.cpp
-            externalReference.cpp
-            freezeFrame.cpp
-            gap.cpp
-            generatorReference.cpp
-            imageSequenceReference.cpp
-            item.cpp
-            linearTimeWarp.cpp
-            marker.cpp
-            mediaReference.cpp
-            missingReference.cpp
-            safely_typed_any.cpp
-            serializableCollection.cpp
-            serializableObject.cpp
-            serializableObjectWithMetadata.cpp
-            serialization.cpp
-            stack.cpp
-            stackAlgorithm.cpp
-            stringUtils.cpp
-            stringUtils.h # stringUtils.h is a private header
-            timeEffect.cpp
-            timeline.cpp
-            track.cpp
-            trackAlgorithm.cpp
-            transition.cpp
-            typeRegistry.cpp
-            unknownSchema.cpp 
-            ${OPENTIMELINEIO_HEADER_FILES})
+    clip.cpp
+    composable.cpp
+    composition.cpp
+    deserialization.cpp
+    effect.cpp
+    errorStatus.cpp
+    externalReference.cpp
+    freezeFrame.cpp
+    gap.cpp
+    generatorReference.cpp
+    imageSequenceReference.cpp
+    item.cpp
+    linearTimeWarp.cpp
+    marker.cpp
+    mediaReference.cpp
+    missingReference.cpp
+    safely_typed_any.cpp
+    serializableCollection.cpp
+    serializableObject.cpp
+    serializableObjectWithMetadata.cpp
+    serialization.cpp
+    stack.cpp
+    stackAlgorithm.cpp
+    stringUtils.cpp
+    stringUtils.h # stringUtils.h is a private header
+    timeEffect.cpp
+    timeline.cpp
+    track.cpp
+    trackAlgorithm.cpp
+    transition.cpp
+    typeRegistry.cpp
+    unknownSchema.cpp 
+    ${OPENTIMELINEIO_HEADER_FILES})
 
 add_library(OTIO::opentimelineio ALIAS opentimelineio)
 
-target_include_directories(opentimelineio PRIVATE
-                           "${IMATH_INCLUDES}"
-                           "${PROJECT_SOURCE_DIR}/src"
-                           "${PROJECT_SOURCE_DIR}/src/deps"
-                           "${PROJECT_SOURCE_DIR}/src/deps/optional-lite/include"
-                           "${PROJECT_SOURCE_DIR}/src/deps/rapidjson/include")
+target_include_directories(opentimelineio
+    PRIVATE       "${IMATH_INCLUDES}"
+                  "${PROJECT_SOURCE_DIR}/src"
+                  "${PROJECT_SOURCE_DIR}/src/deps"
+                  "${PROJECT_SOURCE_DIR}/src/deps/optional-lite/include"
+                  "${PROJECT_SOURCE_DIR}/src/deps/rapidjson/include"
+                  "${IMATH_INCLUDES}")
 
-target_link_libraries(opentimelineio PUBLIC opentime ${OTIO_IMATH_TARGETS})
+target_link_libraries(opentimelineio 
+    PUBLIC opentime ${OTIO_IMATH_TARGETS})
 
 set_target_properties(opentimelineio PROPERTIES
     DEBUG_POSTFIX "${OTIO_DEBUG_POSTFIX}"

tests/CMakeLists.txt

@@ -17,10 +17,14 @@ endforeach()
 
 list(APPEND tests_opentimelineio test_clip)
 foreach(test ${tests_opentimelineio})
-	add_executable(${test} utils.h utils.cpp ${test}.cpp)
-	target_link_libraries(${test} opentimelineio)
-	set_target_properties(${test} PROPERTIES FOLDER tests)
-	add_test(NAME ${test} 
+    add_executable(${test} utils.h utils.cpp ${test}.cpp)
+
+    target_link_libraries(${test} opentimelineio)
+    if (NOT "${IMATH_INCLUDES}" STREQUAL "")
+        target_include_directories(${test} "${IMATH_INCLUDES}")
+    endif()
+    set_target_properties(${test} PROPERTIES FOLDER tests)
+    add_test(NAME ${test} 
            COMMAND ${test}
            # Set the pwd to the source directory so we can load the samples
            # like the python tests do