CMake: Collective UseInternalLibs option

Author: aufau

CMakeLists.txt

@@ -63,7 +63,12 @@ else()
 	set(UseInternalSDL2 OFF)
 	set(UseInternalOpenAL OFF)
 
-	if(MINGW)
+	if(UseInternalLibs)
+		set(UseInternalPNGDefault ON)
+		set(UseInternalJPEGDefault ON)
+		set(UseInternalZLIBDefault ON)
+		set(UseInternalMiniZipDefault ON)
+	elseif(MINGW)
 		set(UseInternalPNGDefault OFF)
 		set(UseInternalJPEGDefault OFF)
 		set(UseInternalZLIBDefault OFF)
@@ -80,7 +85,8 @@ else()
 		set(UseInternalMiniZipDefault OFF)
 		set(UseInternalSDL2 OFF)
 	endif()
-	
+
+	option(UseInternalLibs "Whether to use included libraries instead of locally installed ones")
 	option(UseInternalPNG "Whether to use the included libpng instead of a locally installed one" ${UseInternalPNGDefault})
 	option(UseInternalJPEG "Whether to use the included libjpeg instead of a locally installed one" ${UseInternalJPEGDefault})
 	option(UseInternalZLIB "Whether to use the included zlib instead of a locally installed one" ${UseInternalZLIBDefault})