correct the pyigl.so path given to strip command

Former-commit-id: 2fa7acb85187999e89da076af720ab27bfe09137

python/CMakeLists.txt

@@ -188,7 +188,7 @@ elseif (UNIX)
     endif()
 
     if (NOT ${U_CMAKE_BUILD_TYPE} MATCHES DEBUG)
-      add_custom_command(TARGET pyigl POST_BUILD COMMAND strip -u -r ${CMAKE_CURRENT_BINARY_DIR}/../pyigl.so)
+      add_custom_command(TARGET pyigl POST_BUILD COMMAND strip -u -r ${PROJECT_SOURCE_DIR}/pyigl.so)
     endif()
   else()
 
@@ -198,7 +198,7 @@ elseif (UNIX)
     endif()
 
     if (NOT ${U_CMAKE_BUILD_TYPE} MATCHES DEBUG)
-      add_custom_command(TARGET pyigl POST_BUILD COMMAND strip ${CMAKE_CURRENT_BINARY_DIR}/../pyigl.so)
+      add_custom_command(TARGET pyigl POST_BUILD COMMAND strip ${PROJECT_SOURCE_DIR}/pyigl.so)
     endif()
   endif()
 endif()
@@ -209,7 +209,7 @@ if (LIBIGL_WITH_PYTHON AND LIBIGL_WITH_NANOGUI)
   add_custom_target(copy ALL)
   add_custom_command(
         TARGET copy
-        COMMAND ${CMAKE_COMMAND} -E copy ${NANOGUI_LIB} ${CMAKE_CURRENT_BINARY_DIR}/../
+        COMMAND ${CMAKE_COMMAND} -E copy ${NANOGUI_LIB} ${PROJECT_SOURCE_DIR}
         )
   add_dependencies(copy pyigl)