Use project-local CMake variables

doc/CMakeLists.txt

@@ -3,7 +3,7 @@ find_package(Doxygen REQUIRED)
 
 # set the input and output documentation paths
 set(DOXYGEN_INPUT_DIR ${PROJECT_SOURCE_DIR})
-set(DOXYGEN_OUTPUT_DIR ${CMAKE_BINARY_DIR}/doc)
+set(DOXYGEN_OUTPUT_DIR ${CMAKE_CURRENT_BINARY_DIR})
 
 # see if we can generate the CHM documentation
 if(SFML_OS_WINDOWS)

src/CSFML/CMakeLists.txt

@@ -5,7 +5,7 @@ include(${PROJECT_SOURCE_DIR}/cmake/Macros.cmake)
 include_directories(${PROJECT_SOURCE_DIR}/src)
 
 # set the output directory for CSFML libraries
-set(LIBRARY_OUTPUT_PATH "${CMAKE_BINARY_DIR}/lib")
+set(LIBRARY_OUTPUT_PATH "${PROJECT_BINARY_DIR}/lib")
 
 # define the export symbol
 add_definitions(-DCSFML_EXPORTS)