Fix for OpenCV 4

alexdewar · lava · commit 277221701102 · 2019-08-22T15:47:42.000+02:00
In the latest version of OpenCV, several constants were removed in
favour of enum classes. Fix by #define'ing the ones we need.
diff --git a/matplotlibcpp.h b/matplotlibcpp.h
@@ -17,8 +17,17 @@
 #  include <numpy/arrayobject.h>
 
 #  ifdef WITH_OPENCV
-#  include <opencv2/opencv.hpp>
+#    include <opencv2/opencv.hpp>
 #  endif // WITH_OPENCV
+
+/*
+ * A bunch of constants were removed in OpenCV 4 in favour of enum classes, so
+ * define the ones we need here.
+ */
+#  if CV_MAJOR_VERSION > 3
+#    define CV_BGR2RGB cv::COLOR_BGR2RGB
+#    define CV_BGRA2RGBA cv::COLOR_BGRA2RGBA
+#  endif
 #endif // WITHOUT_NUMPY
 
 #if PY_MAJOR_VERSION >= 3
