nixpkgs/pkgs/development/libraries/opencv/cmake-don-t-use-OpenCVFindOpenEXR.patch

From 6d988c08e852379a163ecd20df8639196d84d014 Mon Sep 17 00:00:00 2001
From: Bernardo Meurer <meurerbernardo@gmail.com>
Date: Sun, 26 Apr 2020 14:50:25 -0700
Subject: [PATCH] cmake: don't use OpenCVFindOpenEXR

Use find_package for this.
---
 CMakeLists.txt                  |  2 ++
 cmake/OpenCVFindLibsGrfmt.cmake | 15 +++------------
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4c0b3880fc..0360469350 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,6 +14,8 @@ FATAL: In-source builds are not allowed.
 ")
 endif()
 
+# the future!
+include(FindPkgConfig)
 
 include(cmake/OpenCVMinDepVersions.cmake)
 
diff --git a/cmake/OpenCVFindLibsGrfmt.cmake b/cmake/OpenCVFindLibsGrfmt.cmake
index 0beaf19317..4c5e46e615 100644
--- a/cmake/OpenCVFindLibsGrfmt.cmake
+++ b/cmake/OpenCVFindLibsGrfmt.cmake
@@ -227,20 +227,11 @@ endif()
 # --- OpenEXR (optional) ---
 if(WITH_OPENEXR)
   ocv_clear_vars(HAVE_OPENEXR)
-  if(NOT BUILD_OPENEXR)
-    include("${OpenCV_SOURCE_DIR}/cmake/OpenCVFindOpenEXR.cmake")
-  endif()
-
+  pkg_check_modules(OPENEXR OpenEXR)
   if(OPENEXR_FOUND)
     set(HAVE_OPENEXR YES)
-  else()
-    ocv_clear_vars(OPENEXR_INCLUDE_PATHS OPENEXR_LIBRARIES OPENEXR_ILMIMF_LIBRARY OPENEXR_VERSION)
-
-    set(OPENEXR_LIBRARIES IlmImf)
-    add_subdirectory("${OpenCV_SOURCE_DIR}/3rdparty/openexr")
-    if(OPENEXR_VERSION)  # check via TARGET doesn't work
-      set(HAVE_OPENEXR YES)
-    endif()
+    set(OPENEXR_INCLUDE_PATHS ${OPENEXR_INCLUDE_DIRS})
+    set(OPENEXR_LIBRARIES ${OPENEXR_LIBRARIES})
   endif()
 endif()
 
-- 
2.26.1