--- ray/src/hd/CMakeLists.txt	2012/05/30 18:31:11	1.6
+++ ray/src/hd/CMakeLists.txt	2014/03/20 22:49:21	1.7
@@ -20,13 +20,14 @@ if(UNIX)
   target_link_libraries(rhpict rtrad)
   install(TARGETS rholo rhoptimize rhpict RUNTIME DESTINATION bin) 
 
-
-	add_executable(x11.hdi rhdisp.c rhdisp2.c viewbeams.c rhd_x11.c rhd_qtree.c rhd_qtree2r.c rhd_ctab.c holo.c)
-	target_link_libraries (x11.hdi rtrad ${X11_LIBRARIES})
-  if(CMAKE_SYSTEM_NAME STREQUAL "SunOS")
-    target_link_libraries(x11.hdi rt)
+  if(X11_FOUND)
+    add_executable(x11.hdi rhdisp.c rhdisp2.c viewbeams.c rhd_x11.c rhd_qtree.c rhd_qtree2r.c rhd_ctab.c holo.c)
+    target_link_libraries (x11.hdi rtrad ${X11_LIBRARIES})
+    if(CMAKE_SYSTEM_NAME STREQUAL "SunOS")
+      target_link_libraries(x11.hdi rt)
+    endif()
+    install(TARGETS x11.hdi RUNTIME DESTINATION bin)
   endif()
-	install(TARGETS x11.hdi RUNTIME DESTINATION bin)
 endif()