My first CMake

cmake_minimum_required(VERSION 3.2)
project(Terralysis)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

set(INTERFACE_FILES main.cpp)
file(GLOB_RECURSE SOURCE_FILES src/*.cpp)
file(GLOB_RECURSE TEST_FILES test/*.cpp)
set(TERRALYSIS_DEPS png)

add_executable(Terralysis ${INTERFACE_FILES} ${SOURCE_FILES})
target_include_directories(Terralysis PUBLIC include)
target_link_libraries(Terralysis ${TERRALYSIS_DEPS})

# Google Test Framework
find_package(GTest QUIET)
if (GTEST_FOUND)
  set(GTEST_DEPS ${GTEST_MAIN_LIBRARIES} ${GTEST_LIBRARIES} pthread)

  add_executable(TerralysisTesting ${TEST_FILES} ${SOURCE_FILES})
  target_include_directories(TerralysisTesting PUBLIC include)
  target_include_directories(TerralysisTesting PUBLIC ${GTEST_INCLUDE_DIRS})
  target_link_libraries(TerralysisTesting ${GTEST_DEPS} ${TERRALYSIS_DEPS})
  add_test(TerralysisTests TerralysisTesting)
else()
  message("GTest framework is missing. Test binary not generated.")
endif()