Look for highgui.h in addition to the opencv package.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/libpipi/trunk@4692 92316355-f0b4-4df1-b90c-862c8a59935f

configure.ac

@@ -121,7 +121,15 @@ AM_CONDITIONAL(USE_SDL, test "${ac_cv_my_have_sdl}" = "yes")
 # Use OpenCV?
 ac_cv_my_have_opencv="no"
 OPENCV="no"
-PKG_CHECK_MODULES(OPENCV, opencv, [ac_cv_my_have_opencv="yes"], [:])
+#FIXME: check for highgui, too.
+PKG_CHECK_MODULES(OPENCV, opencv,
+ [save_CPPFLAGS="${CPPFLAGS}"
+  CPPFLAGS="${CPPFLAGS} ${OPENCV_CFLAGS}"
+  AC_CHECK_HEADERS(highgui.h,
+   [ac_cv_my_have_opencv="yes"],
+   [:])
+  CPPFLAGS="${save_CPPFLAGS}"],
+ [:])
 if test "${ac_cv_my_have_opencv}" != "no"; then
   AC_DEFINE(USE_OPENCV, 1, Define to 1 to use OpenCV)
 fi