From cd95c4635a10c64f85e2704e1fa74e31087d9a46 Mon Sep 17 00:00:00 2001
From: Hans-Kristian Arntzen <post@themaister.net>
Date: Wed, 22 Jan 2025 20:06:30 +0100
Subject: [PATCH] Add support for linking against SDL3 as a system package.

---
 CMakeLists.txt                       |  1 +
 application/input/CMakeLists.txt     |  8 +++++++-
 application/platforms/CMakeLists.txt | 16 ++++++++++------
 third_party/CMakeLists.txt           |  2 +-
 4 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6293aaa4..3df03b1f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -53,6 +53,7 @@ option(GRANITE_FFMPEG "Enable FFmpeg." OFF)
 option(GRANITE_FFMPEG_VULKAN "Enable experimental Vulkan HW decode support in FFmpeg." OFF)
 option(GRANITE_FAST_MATH "Enable fast math." ON)
 option(GRANITE_SHIPPING "Disable code paths not related to development." OFF)
+option(GRANITE_SYSTEM_SDL "Use system SDL3 instead of vendored submodule." OFF)
 
 if (GRANITE_FAST_MATH)
     message("Enabling fast math.")
diff --git a/application/input/CMakeLists.txt b/application/input/CMakeLists.txt
index 3df5c6e5..1f414441 100644
--- a/application/input/CMakeLists.txt
+++ b/application/input/CMakeLists.txt
@@ -4,5 +4,11 @@ target_link_libraries(granite-input PUBLIC granite-util granite-event granite-ma
 
 if (${GRANITE_PLATFORM} MATCHES "SDL")
     add_granite_internal_static_lib(granite-input-sdl input_sdl.cpp input_sdl.hpp)
-    target_link_libraries(granite-input-sdl PUBLIC granite-input SDL3-static)
+    target_link_libraries(granite-input-sdl PUBLIC granite-input)
+    if (GRANITE_SYSTEM_SDL)
+        find_package(SDL3 REQUIRED)
+        target_link_libraries(granite-input-sdl PUBLIC SDL3::SDL3-shared)
+    else()
+        target_link_libraries(granite-input-sdl PUBLIC SDL3-static)
+    endif()
 endif()
\ No newline at end of file
diff --git a/application/platforms/CMakeLists.txt b/application/platforms/CMakeLists.txt
index 8a7c0699..bd62efee 100644
--- a/application/platforms/CMakeLists.txt
+++ b/application/platforms/CMakeLists.txt
@@ -31,13 +31,17 @@ elseif (${GRANITE_PLATFORM} MATCHES "libretro")
     target_include_directories(granite-platform PRIVATE ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/libretro)
 elseif (${GRANITE_PLATFORM} MATCHES "SDL")
     add_granite_internal_static_lib(granite-platform application_sdl3.cpp)
-    # For non-vendored version, but SDL3 is not stable yet as far as I can tell.
-    #find_package(SDL3 REQUIRED CONFIG REQUIRED COMPONENTS SDL3-shared)
-    #target_link_libraries(granite-platform PRIVATE SDL3::SDL3-shared)
-    target_link_libraries(granite-platform PRIVATE SDL3-static granite-input-sdl)
-    if (NOT WIN32)
-        target_link_libraries(granite-platform PRIVATE dl)
+
+    if (GRANITE_SYSTEM_SDL)
+        find_package(SDL3 REQUIRED)
+        target_link_libraries(granite-platform PRIVATE SDL3::SDL3-shared)
+    else()
+        target_link_libraries(granite-platform PRIVATE SDL3-static)
+        if (NOT WIN32)
+            target_link_libraries(granite-platform PRIVATE dl)
+        endif()
     endif()
+    target_link_libraries(granite-platform PRIVATE granite-input-sdl)
 elseif (${GRANITE_PLATFORM} MATCHES "headless")
     add_granite_internal_static_lib(granite-platform application_headless_wrapper.cpp)
 elseif (${GRANITE_PLATFORM} MATCHES "null")
diff --git a/third_party/CMakeLists.txt b/third_party/CMakeLists.txt
index 4abff1ad..8525cd32 100644
--- a/third_party/CMakeLists.txt
+++ b/third_party/CMakeLists.txt
@@ -113,7 +113,7 @@ else()
 endif()
 target_link_libraries(granite-volk PRIVATE granite-volk-headers)
 
-if ((NOT ANDROID) AND (${GRANITE_PLATFORM} MATCHES "SDL"))
+if ((NOT ANDROID) AND (${GRANITE_PLATFORM} MATCHES "SDL") AND (NOT GRANITE_SYSTEM_SDL))
     set(SDL_SHARED OFF CACHE BOOL "" FORCE)
     set(SDL_STATIC ON CACHE BOOL "" FORCE)
     set(SDL_TIMERS ON CACHE BOOL "" FORCE)