message: add advanced CMake option to toggle building the ISPC device
diff: @@ -461,6 +461,10 @@ COMPONENT
  lib
  )
  +OPTION(OSPRAY_BUILD_ISPC_DEVICE "Build ISPC Device" ON)
  +MARK_AS_ADVANCED(OSPRAY_BUILD_ISPC_DEVICE)
  +
  +IF(OSPRAY_BUILD_ISPC_DEVICE)
  OSPRAY_CREATE_LIBRARY(ospray_module_ispc
  ${OSPRAY_ISPC_DEVICE_SOURCES}
  LINK
  @@ -470,6 +474,7 @@ LINK
  COMPONENT
  lib
  )
  +ENDIF()
  # build ospTutorial, for testing
  ADD_EXECUTABLE(ospTutorial ../apps/ospTutorial.c)
  