cmake: simplify packages to ALIASed libraries

cmake/modules/FindBullet.cmake

@@ -1,17 +1,17 @@
 # Override CMake's FindBullet module:
-# create an IMPORTED TARGET
+# - create a bullet::bullet TARGET
 
 include("${CMAKE_ROOT}/Modules/FindBullet.cmake")
 
 if(BULLET_FOUND AND NOT TARGET bullet::bullet)
-  list(GET BULLET_LIBRARIES 0 BULLET_FIRST_LIBRARY)
-  set(BULLET_OTHER_LIBRARIES "${BULLET_LIBRARIES}")
-  list(REMOVE_AT BULLET_OTHER_LIBRARIES 0)
-  add_library(bullet::bullet UNKNOWN IMPORTED)
-  set_target_properties(bullet::bullet PROPERTIES
-    IMPORTED_LINK_INTERFACE_LANGUAGES "C;CXX"
-    IMPORTED_LOCATION "${BULLET_FIRST_LIBRARY}"
-    INTERFACE_LINK_LIBRARIES "${BULLET_OTHER_LIBRARIES}"
-    INTERFACE_INCLUDE_DIRECTORIES "${BULLET_INCLUDE_DIR}"
-    )
+    add_library(bullet INTERFACE)
+    target_link_libraries(bullet
+        INTERFACE
+            ${BULLET_LIBRARIES}
+        )
+    target_include_directories(bullet SYSTEM
+        INTERFACE
+            "${BULLET_INCLUDE_DIR}"
+        )
+    add_library(bullet::bullet ALIAS bullet)
 endif()

cmake/modules/FindFFmpeg.cmake

@@ -62,14 +62,14 @@ include(FindPackageHandleStandardArgs)
 find_package_handle_standard_args(FFmpeg DEFAULT_MSG FFMPEG_LIBRARIES FFMPEG_INCLUDE_DIR)
 
 if(FFMPEG_FOUND AND NOT TARGET ffmpeg::ffmpeg)
-  list(GET FFMPEG_LIBRARIES 0 FFMPEG_FIRST_LIBRARY)
-  set(FFMPEG_OTHER_LIBRARIES "${FFMPEG_LIBRARIES}")
-  list(REMOVE_AT FFMPEG_OTHER_LIBRARIES 0)
-  add_library(ffmpeg::ffmpeg UNKNOWN IMPORTED)
-  set_target_properties(ffmpeg::ffmpeg PROPERTIES
-    IMPORTED_LINK_INTERFACE_LANGUAGES "C;CXX"
-    IMPORTED_LOCATION "${FFMPEG_FIRST_LIBRARY}"
-    INTERFACE_LINK_LIBRARIES "${FFMPEG_OTHER_LIBRARIES}"
-    INTERFACE_INCLUDE_DIRECTORIES "${FFMPEG_INCLUDE_DIR}"
-    )
+    add_library(ffmpeg INTERFACE)
+    target_link_libraries(ffmpeg
+        INTERFACE
+            ${FFMPEG_LIBRARIES}
+        )
+    target_include_directories(ffmpeg SYSTEM
+        INTERFACE
+            "${FFMPEG_INCLUDE_DIR}"
+        )
+    add_library(ffmpeg::ffmpeg ALIAS ffmpeg)
 endif()

cmake/modules/FindGLM.cmake

@@ -65,8 +65,10 @@ IF(GLM_FOUND)
 ENDIF(GLM_FOUND)
 
 if(GLM_FOUND AND NOT TARGET glm::glm)
-  add_library(glm::glm INTERFACE IMPORTED)
-  set_target_properties(glm::glm PROPERTIES
-    INTERFACE_INCLUDE_DIRECTORIES "${GLM_INCLUDE_DIR}"
-    )
+    add_library(glm INTERFACE)
+    target_include_directories(glm SYSTEM
+        INTERFACE
+            "${GLM_INCLUDE_DIR}"
+        )
+    add_library(glm::glm ALIAS glm)
 endif()

cmake/modules/FindOpenAL.cmake

@@ -1,13 +1,17 @@
-# Override CMake's FindBullet module:
-# create an IMPORTED TARGET
+# Override CMake's FindOpenAL module:
+# - create a OpenAL::OpenAL target
 
 include("${CMAKE_ROOT}/Modules/FindOpenAL.cmake")
 
 if(OPENAL_FOUND AND NOT TARGET OpenAL::OpenAL)
-  add_library(OpenAL::OpenAL UNKNOWN IMPORTED)
-  set_target_properties(OpenAL::OpenAL PROPERTIES
-    IMPORTED_LINK_INTERFACE_LANGUAGES "C;CXX"
-    IMPORTED_LOCATION "${OPENAL_LIBRARY}"
-    INTERFACE_INCLUDE_DIRECTORIES "${OPENAL_INCLUDE_DIR}"
-    )
+    add_library(OpenAL INTERFACE)
+    target_link_libraries(OpenAL
+        INTERFACE
+            "${OPENAL_LIBRARY}"
+        )
+    target_include_directories(OpenAL SYSTEM
+        INTERFACE
+            "${OPENAL_INCLUDE_DIR}"
+        )
+    add_library(OpenAL::OpenAL ALIAS OpenAL)
 endif()

cmake/modules/FindOpenGL.cmake

@@ -1,14 +1,17 @@
+# Override CMake's FindOpenGL module:
+# - create a OPENGL::GL TARGET
+
 include("${CMAKE_ROOT}/Modules/FindOpenGL.cmake")
 
 if(OPENGL_FOUND AND NOT TARGET OpenGL::GL)
-  list(GET OPENGL_LIBRARIES 0 OPENGL_FIRST_LIBRARY)
-  set(OPENGL_OTHER_LIBRARIES "${OPENGL_LIBRARIES}")
-  list(REMOVE_AT OPENGL_OTHER_LIBRARIES 0)
-  add_library(OpenGL::GL UNKNOWN IMPORTED)
-  set_target_properties(OpenGL::GL PROPERTIES
-    IMPORTED_LINK_INTERFACE_LANGUAGES "C;CXX"
-    IMPORTED_LOCATION "${OPENGL_FIRST_LIBRARY}"
-    INTERFACE_LINK_LIBRARIES "${OPENGL_OTHER_LIBRARIES}"
-    INTERFACE_INCLUDE_DIRECTORIES "${OPENGL_INCLUDE_DIR}"
-    )
+    add_library(OpenGL INTERFACE)
+    target_link_libraries(OpenGL
+        INTERFACE
+            ${OPENGL_LIBRARIES}
+        )
+    target_include_directories(OpenGL SYSTEM
+        INTERFACE
+            "${OPENGL_INCLUDE_DIR}"
+        )
+    add_library(OpenGL::GL ALIAS OpenGL)
 endif()

cmake/modules/FindSDL2.cmake

@@ -169,7 +169,7 @@ IF(SDL2_LIBRARY_TEMP)
   IF(MINGW)
     SET(SDL2_LIBRARY_TEMP ${MINGW32_LIBRARY} ${SDL2_LIBRARY_TEMP})
   ENDIF(MINGW)
-  
+
   IF(WIN32)
     SET(SDL2_LIBRARY_TEMP winmm imm32 version msimg32 ${SDL2_LIBRARY_TEMP})
   ENDIF(WIN32)
@@ -196,13 +196,14 @@ IF(SDL2_STATIC)
 ENDIF(SDL2_STATIC)
 
 if(SDL2_FOUND AND NOT TARGET SDL2::SDL2)
-  set(SDL2_EXTRA_LIBS "${SDL2_LIBRARY_TEMP}")
-  list(REMOVE_ITEM SDL2_EXTRA_LIBS "${SDL2_LIBRARY_PATH}")
-  add_library(SDL2::SDL2 UNKNOWN IMPORTED)
-  set_target_properties(SDL2::SDL2 PROPERTIES
-    IMPORTED_LINK_INTERFACE_LANGUAGES "C;CXX"
-    IMPORTED_LINK_DEPENDENT_LIBRARIES "${SDL2_EXTRA_LIBS}"
-    IMPORTED_LOCATION "${SDL2_LIBRARY_PATH}"
-    INTERFACE_INCLUDE_DIRECTORIES "${SDL2_INCLUDE_DIR}"
-    )
+    add_library(SDL2 INTERFACE)
+    target_link_libraries(SDL2
+        INTERFACE
+            ${SDL2_LIBRARY}
+        )
+    target_include_directories(SDL2 SYSTEM
+        INTERFACE
+            "${SDL2_INCLUDE_DIR}"
+        )
+    add_library(SDL2::SDL2 ALIAS SDL2)
 endif()