Add top level CMakeLists.txt

This file currently acts as a placeholder for optional/CMakeLists.txt to
enable automatic builds. Maybe it's a good idea to move
optional/CMakeLists.txt here.


Former-commit-id: f77e8ba252063aa3ece5e5d1b58eec8222666529

CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.1)
+
+include(${CMAKE_CURRENT_LIST_DIR}/optional/CMakeLists.txt)

optional/CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.1)
 project(libigl)
 
-set (CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/../shared/cmake")
+set (CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/../shared/cmake")
 # These ensure that lib*.a are placed in the directory where `cmake
 # ../optional/` was issued.
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})
@@ -9,7 +9,7 @@ set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})
 
 ### conditionally compile certain modules depending on libraries found on the system
-list(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/../shared/cmake)
+list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_LIST_DIR}/../shared/cmake)
 find_package(CGAL QUIET COMPONENTS Core)
 find_package(MATLAB QUIET)
 find_package(MOSEK)