if no b/a area enabled some speed up when opening images

rtengine/CMakeLists.txt

@@ -0,0 +1,28 @@
+
+include_directories (${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/../rtexif
+    ${EXTRA_INCDIR} ${GTHREAD_INCLUDE_DIRS} ${GOBJECT_INCLUDE_DIRS} ${GLIB2_INCLUDE_DIRS}
+    ${GLIBMM_INCLUDE_DIRS} ${IPTCDATA_INCLUDE_DIRS} ${LCMS_INCLUDE_DIRS}
+	${CMAKE_CURRENT_SOURCE_DIR}/../rtgui ${GTKMM_INCLUDE_DIRS})
+link_directories (${CMAKE_CURRENT_SOURCE_DIR}/../rtexif ${EXTRA_LIBDIR} ${GTHREAD_LIBRARY_DIRS}
+    ${GOBJECT_LIBRARY_DIRS} ${GLIB2_LIBRARY_DIRS} ${GLIBMM_LIBRARY_DIRS}
+    ${IPTCDATA_LIBRARY_DIRS} ${LCMS_LIBRARY_DIRS})
+
+set (RTENGINESOURCEFILES colortemp.cc curves.cc dcraw.cc iccstore.cc
+    image8.cc image16.cc imagedata.cc imageio.cc improcfun.cc init.cc dcrop.cc
+    loadinitial.cc procparams.cc rawimagesource.cc shmap.cc simpleprocess.cc refreshmap.cc
+    stdimagesource.cc myfile.cc iccjpeg.c hlmultipliers.cc improccoordinator.cc
+    processingjob.cc rtthumbnail.cc utils.cc labimage.cc
+    iplab2rgb.cc ipsharpen.cc iptransform.cc ipresize.cc
+    wavelet_dec.cc ipequalizer.cc)
+
+add_library (rtengine ${RTENGINESOURCEFILES})
+#It may be nice to store library version too
+IF (BUILD_SHARED_LIBS)
+    install (TARGETS rtengine DESTINATION ${LIBDIR})
+ENDIF (BUILD_SHARED_LIBS)
+
+set_target_properties (rtengine PROPERTIES COMPILE_FLAGS "${CMAKE_CXX_FLAGS} -ffast-math -funroll-loops")
+
+target_link_libraries (rtengine rtexif ${EXTRA_LIB} ${GOBJECT_LIBRARIES} ${GTHREAD_LIBRARIES}
+    ${GLIB2_LIBRARIES} ${GLIBMM_LIBRARIES} ${LCMS_LIBRARIES} ${IPTCDATA_LIBRARIES}
+    ${JPEG_LIBRARIES} ${PNG_LIBRARIES} ${TIFF_LIBRARIES} ${ZLIB_LIBRARIES})