Use INTERFACE targets for SDL2 libraries

Author: Grumbel

CMakeLists.txt

@@ -205,7 +205,7 @@ target_compile_definitions(supertux2_lib PUBLIC -DGLM_ENABLE_EXPERIMENTAL)
 
 if(WIN32)
   add_executable(supertux2 WIN32 src/main.cpp ${CMAKE_CURRENT_SOURCE_DIR}/data/images/engine/icons/supertux.rc)
-  target_link_libraries(supertux2 ${SDL2MAIN_LIBRARIES})
+  target_link_libraries(supertux2 SDL2main)
 else()
   add_executable(supertux2 src/main.cpp)
 endif()
@@ -238,14 +238,7 @@ endif()
 
 ## Link supertux binary with squirrel and other libraries
 if(NOT EMSCRIPTEN)
-  target_include_directories(supertux2_lib SYSTEM PUBLIC ${SDL2_INCLUDE_DIRS})
-  target_include_directories(supertux2_lib SYSTEM PUBLIC ${SDL2IMAGE_INCLUDE_DIRS})
-  if(VCPKG_BUILD AND NOT WIN32)
-    target_link_libraries(supertux2_lib PRIVATE SDL2::SDL2main SDL2::SDL2 SDL2::SDL2_image)
-  else()
-    target_link_libraries(supertux2_lib PUBLIC ${SDL2_LIBRARIES})
-    target_link_libraries(supertux2_lib PUBLIC ${SDL2IMAGE_LIBRARIES})
-  endif()
+  target_link_libraries(supertux2_lib PUBLIC SDL2 SDL2_image)
 endif()
 
 target_link_libraries(supertux2_lib PUBLIC SDL2_ttf)

mk/cmake/SuperTux/ProvideSDL2.cmake

@@ -1,9 +1,9 @@
+message(STATUS "Checking for SDL2")
 if(WIN32)
   if(VCPKG_BUILD)
     find_package(SDL2 CONFIG REQUIRED)
     find_library(SDL2IMAGE_LIBRARIES SDL2_image)
     find_library(SDL2MAIN_LIBRARIES SDL2main)
-    message(STATUS "SDL2_INCLUDE_DIR is ${SDL2_INCLUDE_DIRS}")
   else()
     find_path(SDL2_INCLUDE_DIRS NAMES SDL.h PATHS "${DEPENDENCY_FOLDER}/include/SDL2")
     find_path(SDL2IMAGE_INCLUDE_DIRS NAMES SDL_image.h PATHS "${DEPENDENCY_FOLDER}/include/SDL2_image")
@@ -25,7 +25,6 @@ else()
       set(SDL2IMAGE_INCLUDE_DIRS ${SDL2IMAGE_INCLUDE_DIRS}/SDL2)
       find_library(SDL2_LIBRARIES SDL2)
       find_library(SDL2IMAGE_LIBRARIES SDL2_image)
-      message(STATUS "SDL2_INCLUDE_DIR is ${SDL2_INCLUDE_DIRS}")
     elseif(CMAKE_SIZEOF_VOID_P EQUAL 4)
       # 32-bit
       find_library(SDL2_LIBRARIES SDL2)
@@ -34,18 +33,38 @@ else()
       find_path(SDL2IMAGE_INCLUDE_DIRS SDL2/SDL_image.h)
       set(SDL2_INCLUDE_DIRS ${SDL2_INCLUDE_DIRS}/SDL2)
       set(SDL2IMAGE_INCLUDE_DIRS ${SDL2IMAGE_INCLUDE_DIRS}/SDL2)
-      message(STATUS "SDL LIBS: ${SDL2_LIBRARIES}")
-      message(STATUS "SDL INCL: ${SDL2_INCLUDE_DIRS}")
     else()
       # 64-bit
       include(FindPkgConfig)
       pkg_search_module(SDL2 REQUIRED sdl2>=2.0.1)
       pkg_search_module(SDL2IMAGE REQUIRED SDL2_image>=2.0.0)
+      set(SDL2_LIBRARIES "${SDL2_LINK_LIBRARIES}")
+      set(SDL2IMAGE_LIBRARIES "${SDL2IMAGE_LINK_LIBRARIES}")
     endif()
   endif()
 endif()
 set(HAVE_SDL TRUE)
 
+message(STATUS "  SDL2_LIBRARIES: ${SDL2_LIBRARIES}")
+message(STATUS "  SDL2_INCLUDE_DIRS: ${SDL2_INCLUDE_DIRS}")
+message(STATUS "  SDL2IMAGE_LIBRARIES: ${SDL2IMAGE_LIBRARIES}")
+message(STATUS "  SDL2IMAGE_INCLUDE_DIRS: ${SDL2IMAGE_INCLUDE_DIRS}")
+
+add_library(SDL2 INTERFACE)
+set_target_properties(SDL2 PROPERTIES
+  INTERFACE_INCLUDE_DIRECTORIES "${SDL2_INCLUDE_DIRS}"
+  INTERFACE_LINK_LIBRARIES "${SDL2_LIBRARIES}")
+
+add_library(SDL2main INTERFACE)
+set_target_properties(SDL2main PROPERTIES
+  INTERFACE_INCLUDE_DIRECTORIES "${SDL2_INCLUDE_DIRS}"
+  INTERFACE_LINK_LIBRARIES "${SDL2MAIN_LIBRARIES}")
+
+add_library(SDL2_image INTERFACE)
+set_target_properties(SDL2_image PROPERTIES
+  INTERFACE_INCLUDE_DIRECTORIES "${SDL2IMAGE_INCLUDE_DIRS}"
+  INTERFACE_LINK_LIBRARIES "${SDL2IMAGE_LIBRARIES}")
+
 mark_as_advanced(
   SDL2_INCLUDE_DIRS
   SDL2_LIBRARIES