cmake: add a new GTK3.0 option

Thanks #micove for the patch

build.sh

@@ -41,6 +41,7 @@ for ARG in "$@"; do
         --asan        ) flags+=(-DUSE_ASAN=TRUE) ;;
         --wx28        ) flags+=(-DWX28_API=TRUE) ;;
         --wx30        ) flags+=(-DWX28_API=FALSE) ;;
+        --gtk3        ) flags+=(-DGTK3_API=TRUE) ;;
         --64-bit-dont-work ) flags+=(-D64BIT_BUILD_DONT_WORK=TRUE) ;;
         --no-simd     ) flags+=(-DDISABLE_ADVANCE_SIMD=TRUE) ;;
         -D*           ) flags+=($ARG) ;;
@@ -51,21 +52,25 @@ for ARG in "$@"; do
             echo "--dev / --devel : Build PCSX2 as a Development build."
             echo "--debug         : Build PCSX2 as a Debug build."
             echo "--release       : Build PCSX2 as a Release build."
+            echo
             echo "--clean         : Do a clean build."
+            echo "--extra         : Build all plugins"
+            echo
             echo "** Developper option **"
             echo "--clang         : Build with Clang/llvm"
-            echo "--extra         : Build all plugins"
+            echo "--asan          : Enable Address sanitizer"
-            echo "--asan          : Enable with Address sanitizer"
             echo
             echo "--wx28          : Force wxWidget 2.8"
             echo "--wx30          : Allow to use wxWidget 3.0"
             echo "--glsl          : Replace CG backend of ZZogl by GLSL"
             echo "--egl           : Replace GLX by EGL (ZZogl plugins only)"
             echo "--sdl2          : Build with SDL2 (crash if wx is linked to SDL1)"
-            echo "--gles          : Replace openGL backend of GSdx by openGLES3"
+            echo "--gles          : Replace openGL backend of GSdx by openGLES3.1"
             echo
+            echo "** Hardcode Developper option **"
             echo "--64-bit-dont-work : Don't use it!"
             echo "--no-simd       : Only allow sse2"
+            echo "--gtk3          : replace GTK2 by GTK3"
             exit 1
     esac
 done

cmake/BuildParameters.cmake

@@ -34,6 +34,7 @@ option(XDG_STD "Use XDG standard path instead of the standard PCSX2 path")
 option(EXTRA_PLUGINS "Build various 'extra' plugins")
 option(SDL2_API "Use SDL2 on spu2x and onepad")
 option(WX28_API "Force wxWidget 2.8 lib")
+option(GTK3_API "Use GTK3 api")
 
 if(PACKAGE_MODE)
     if(NOT DEFINED PLUGIN_DIR)
@@ -239,6 +240,7 @@ else()
     set(ASAN_FLAG "")
 endif()
 
+# Note: -DGTK_DISABLE_DEPRECATED can be used to test a build without gtk deprecated feature. It could be useful to port to a newer API
 set(DEFAULT_GCC_FLAG "${ARCH_FLAG} ${COMMON_FLAG} ${DEFAULT_WARNINGS} ${HARDENING_FLAG} ${DEBUG_FLAG} ${ASAN_FLAG}")
 # c++ only flags
 set(DEFAULT_CPP_FLAG "${DEFAULT_GCC_FLAG} -Wno-invalid-offsetof")

cmake/CheckLib.cmake

@@ -29,7 +29,11 @@ macro(check_lib var lib)
 			include_directories(${${var}_INCLUDE})
 			_internal_message("-- ${lib} found")
 			set(${var}_FOUND 1 CACHE INTERNAL "")
-		else()
+        elseif(${var}_LIBRARIES)
+            _internal_message("-- ${lib} not found (miss include)")
+		elseif(${var}_INCLUDE)
+            _internal_message("-- ${lib} not found (miss lib)")
+        else()
 			_internal_message("-- ${lib} not found")
 		endif()
 	endif()

cmake/SearchForStuff.cmake

@@ -1,12 +1,6 @@
 #-------------------------------------------------------------------------------
 #						Search all libraries on the system
 #-------------------------------------------------------------------------------
-if(Linux)
-    # Most plugins (if not all) and PCSX2 core need gtk2, so set the required flags
-    find_package(GTK2 REQUIRED gtk)
-    find_package(X11)
-endif()
-
 ## Use cmake package to find module
 find_package(ALSA)
 find_package(BZip2)
@@ -50,12 +44,26 @@ else()
     find_package(SDL)
 endif()
 
+if (Linux)
+    find_package(X11)
+    # Most plugins (if not all) and PCSX2 core need gtk2, so set the required flags
+    if (GTK3_API)
+        check_lib(GTK3 gtk+-3.0 gtk/gtk.h)
+    else()
+        find_package(GTK2 REQUIRED gtk)
+    endif()
+endif()
+
 #----------------------------------------
 #		    Use system include
 #----------------------------------------
 if(Linux)
 	if(GTK2_FOUND)
 		include_directories(${GTK2_INCLUDE_DIRS})
+    elseif(GTK3_FOUND)
+		include_directories(${GTK3_INCLUDE_DIRS})
+        # A lazy solution
+        set(GTK2_LIBRARIES ${GTK3_LIBRARIES})
 	endif()
 
 	if(X11_FOUND)