robust discovery & link to openexr in opencv 3.x

recipes/opencv/3.x/conandata.yml

@@ -9,3 +9,14 @@ sources:
       sha256: "c8919dfb5ead6be67534bf794cb0925534311f1cd5c6680f8164ad1813c88d13"
     - url: "https://github.com/opencv/opencv_contrib/archive/3.4.12.tar.gz"
       sha256: "b207024589674dd2efc7c25740ef192ee4f3e0783e773e2d49a198c37e3e7570"
+patches:
+  "3.4.17":
+    - patch_file: "patches/3.4.17-0001-find-openexr.patch"
+      patch_description: "Robust discovery & injection of OpenEXR"
+      patch_type: "conan"
+      base_path: "src"
+  "3.4.12":
+    - patch_file: "patches/3.4.12-0001-find-openexr.patch"
+      patch_description: "Robust discovery & injection of OpenEXR"
+      patch_type: "conan"
+      base_path: "src"

recipes/opencv/3.x/conanfile.py

@@ -1,6 +1,6 @@
 from conan import ConanFile
 from conan.errors import ConanInvalidConfiguration
-from conan.tools.files import copy, get, rename, replace_in_file, rmdir, save
+from conan.tools.files import apply_conandata_patches, copy, export_conandata_patches, get, rename, replace_in_file, rmdir, save
 from conan.tools.microsoft import is_msvc, is_msvc_static_runtime
 from conan.tools.scm import Version
 from conans import CMake
@@ -51,7 +51,6 @@ class OpenCVConan(ConanFile):
     }
 
     short_paths = True
-    exports_sources = "CMakeLists.txt"
     generators = "cmake", "cmake_find_package"
     _cmake = None
 
@@ -67,6 +66,10 @@ def _contrib_folder(self):
     def _build_folder(self):
         return os.path.join(self.source_folder, "build")
 
+    def export_sources(self):
+        copy(self, "CMakeLists.txt", src=self.recipe_folder, dst=self.export_sources_folder)
+        export_conandata_patches(self)
+
     def config_options(self):
         if self.settings.os == "Windows":
             del self.options.fPIC
@@ -126,6 +129,7 @@ def source(self):
             destination=self._contrib_folder, strip_root=True)
 
     def _patch_sources(self):
+        apply_conandata_patches(self)
         rmdir(self, os.path.join(self._source_folder, "3rdparty"))
         if self.options.contrib:
             freetype_cmake = os.path.join(self._contrib_folder, "modules", "freetype", "CMakeLists.txt")
@@ -277,8 +281,6 @@ def _configure_cmake(self):
 
         if is_msvc(self):
             self._cmake.definitions["BUILD_WITH_STATIC_CRT"] = is_msvc_static_runtime(self)
-        if self.options.with_openexr:
-            self._cmake.definitions["OPENEXR_ROOT"] = self.dependencies["openexr"].package_folder.replace("\\", "/")
         self._cmake.definitions["ENABLE_PIC"] = self.options.get_safe("fPIC", True)
         self._cmake.definitions["ENABLE_CCACHE"] = False
 

recipes/opencv/3.x/patches/3.4.12-0001-find-openexr.patch

@@ -0,0 +1,18 @@
+--- a/cmake/OpenCVFindOpenEXR.cmake
++++ b/cmake/OpenCVFindOpenEXR.cmake
+@@ -8,6 +8,15 @@
+ # OPENEXR_INCLUDE_PATHS = OpenEXR include directories.
+ # OPENEXR_LIBRARIES = libraries that are needed to use OpenEXR.
+ #
++find_package(OpenEXR REQUIRED)
++if(TARGET OpenEXR::OpenEXR)
++    set(OPENEXR_LIBRARIES OpenEXR::OpenEXR)
++else()
++    set(OPENEXR_LIBRARIES openexr::openexr)
++endif()
++set(OPENEXR_FOUND TRUE)
++set(OPENEXR_VERSION ${OpenEXR_VERSION})
++return()
+
+ SET(OPENEXR_LIBRARIES "")
+ SET(OPENEXR_LIBSEARCH_SUFFIXES "")

recipes/opencv/3.x/patches/3.4.17-0001-find-openexr.patch

@@ -0,0 +1,18 @@
+--- a/cmake/OpenCVFindOpenEXR.cmake
++++ b/cmake/OpenCVFindOpenEXR.cmake
+@@ -8,6 +8,15 @@
+ # OPENEXR_INCLUDE_PATHS = OpenEXR include directories.
+ # OPENEXR_LIBRARIES = libraries that are needed to use OpenEXR.
+ #
++find_package(OpenEXR REQUIRED)
++if(TARGET OpenEXR::OpenEXR)
++    set(OPENEXR_LIBRARIES OpenEXR::OpenEXR)
++else()
++    set(OPENEXR_LIBRARIES openexr::openexr)
++endif()
++set(OPENEXR_FOUND TRUE)
++set(OPENEXR_VERSION ${OpenEXR_VERSION})
++return()
+
+ if(NOT HAVE_CXX11)
+   message(STATUS "OpenEXR: enable C++11 to use external OpenEXR")