Make bare-minimum changes to get SDL3 compiling

CHANGELOG.md

@@ -6,6 +6,10 @@ on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ## [Upcoming Release]
 
 - A CC-BY license was added to `resources/icons` (#944)
+- "Windows Fullscreen" was dropped from the about page: the "Fullscreen" button now
+  always follows "windowed fullscreen" behavior (exclusive fullscreen usage was deemed
+  to be niche).
+- Internal: SDL2 was upgraded to SDL3
 
 ## [0.5.16] - 2024/11/04
 

src/OpenSimCreator/UI/Shared/MainMenu.cpp

@@ -258,16 +258,10 @@ void osc::MainMenuAboutTab::onDraw()
         ui::draw_text_unformatted("window");
         ui::next_column();
 
-        if (ui::draw_button(OSC_ICON_EXPAND " fullscreen"))
-        {
-            App::upd().make_fullscreen();
-        }
-        if (ui::draw_button(OSC_ICON_EXPAND " windowed fullscreen"))
-        {
+        if (ui::draw_button(OSC_ICON_EXPAND " fullscreen")) {
             App::upd().make_windowed_fullscreen();
         }
-        if (ui::draw_button(OSC_ICON_WINDOW_RESTORE " windowed"))
-        {
+        if (ui::draw_button(OSC_ICON_WINDOW_RESTORE " windowed")) {
             App::upd().make_windowed();
         }
         ui::next_column();

src/oscar/CMakeLists.txt

@@ -14,7 +14,7 @@ if (NOT ${OSC_EMSCRIPTEN})
     # source code).
     find_package(OpenGL REQUIRED)
     find_package(glew REQUIRED CONFIG)
-    find_package(SDL2 REQUIRED CONFIG)
+    find_package(SDL3 REQUIRED CONFIG)
     find_package(nativefiledialog REQUIRED CONFIG)
 endif()
 find_package(imgui REQUIRED CONFIG)
@@ -268,7 +268,6 @@ add_library(oscar STATIC
     Maths/Vec3.h
     Maths/Vec4.h
 
-    Platform/Detail/SDL2Helpers.h
     Platform/App.cpp
     Platform/App.h
     Platform/AppClock.h
@@ -647,7 +646,7 @@ target_link_libraries(oscar PRIVATE
     $<$<NOT:$<BOOL:${OSC_EMSCRIPTEN}>>:
         OpenGL::GL
         GLEW::glew_s
-        SDL2::SDL2
+        SDL3::SDL3
         nativefiledialog
     >
 

src/oscar/Graphics/GraphicsImplementation.cpp

@@ -71,7 +71,6 @@
 #include <oscar/Maths/Vec4.h>
 #include <oscar/Maths/VecFunctions.h>
 #include <oscar/Platform/App.h>
-#include <oscar/Platform/Detail/SDL2Helpers.h>
 #include <oscar/Platform/Log.h>
 #include <oscar/Utils/Algorithms.h>
 #include <oscar/Utils/Assertions.h>
@@ -86,8 +85,10 @@
 #include <oscar/Utils/TransparentStringHasher.h>
 #include <oscar/Utils/UID.h>
 
-#include <GL/glew.h>
 #include <ankerl/unordered_dense.h>
+#include <GL/glew.h>
+#include <SDL3/SDL.h>
+#undef main
 
 #include <algorithm>
 #include <array>
@@ -115,6 +116,56 @@ using namespace osc::literals;
 using namespace osc;
 namespace rgs = std::ranges;
 
+namespace osc::sdl
+{
+    // RAII wrapper around `SDL_GLContext` that calls `SDL_GL_DeleteContext` on dtor
+    //     https://wiki.libsdl.org/SDL_GL_DeleteContext
+    class GLContext final {
+    public:
+        GLContext(const GLContext&) = delete;
+        GLContext(GLContext&& tmp) noexcept :
+            context_handle_{std::exchange(tmp.context_handle_, nullptr)}
+        {}
+        GLContext& operator=(const GLContext&) = delete;
+        GLContext& operator=(GLContext&&) = delete;
+        ~GLContext() noexcept
+        {
+            if (context_handle_) {
+                SDL_GL_DestroyContext(context_handle_);
+            }
+        }
+
+        SDL_GLContext get() { return context_handle_; }
+
+    private:
+        friend GLContext GL_CreateContext(SDL_Window* w);
+        GLContext(SDL_GLContext _ctx) :
+            context_handle_{_ctx}
+        {}
+
+        SDL_GLContext context_handle_;
+    };
+
+    // https://wiki.libsdl.org/SDL_GL_CreateContext
+    inline GLContext GL_CreateContext(SDL_Window* w)
+    {
+        const SDL_GLContext ctx = SDL_GL_CreateContext(w);
+
+        if (ctx == nullptr) {
+            throw std::runtime_error{std::string{"SDL_GL_CreateContext failed: "} + SDL_GetError()};
+        }
+
+        return GLContext{ctx};
+    }
+
+    inline int GetOpenGLSwapInterval()
+    {
+        int rv = 0;
+        SDL_GL_GetSwapInterval(&rv);
+        return rv;
+    }
+}
+
 // shader source
 namespace
 {
@@ -5872,15 +5923,15 @@ namespace
         sdl::GLContext ctx = sdl::GL_CreateContext(&window);
 
         // enable the OpenGL context
-        if (SDL_GL_MakeCurrent(&window, ctx.get()) != 0) {
+        if (not SDL_GL_MakeCurrent(&window, ctx.get())) {
             throw std::runtime_error{std::string{"SDL_GL_MakeCurrent failed: "} + SDL_GetError()};
         }
 
         // enable vsync by default
         //
         // vsync can feel a little laggy on some systems, but vsync reduces CPU usage
         // on *constrained* systems (e.g. laptops, which the majority of users are using)
-        if (SDL_GL_SetSwapInterval(-1) != 0) {
+        if (not SDL_GL_SetSwapInterval(-1)) {
             SDL_GL_SetSwapInterval(1);
         }
 
@@ -6118,13 +6169,13 @@ class osc::GraphicsContext::Impl final {
             }
 
             // always read the vsync state back from SDL
-            vsync_enabled_ = SDL_GL_GetSwapInterval() != 0;
+            vsync_enabled_ = sdl::GetOpenGLSwapInterval();
         }
         else {
             // try to disable vsync
 
             SDL_GL_SetSwapInterval(0);
-            vsync_enabled_ = SDL_GL_GetSwapInterval() != 0;
+            vsync_enabled_ = sdl::GetOpenGLSwapInterval();
         }
     }
 
@@ -6260,7 +6311,7 @@ class osc::GraphicsContext::Impl final {
     // maximum number of antiAliasingLevel supported by this hardware's OpenGL MSXAA API
     AntiAliasingLevel max_aa_level_ = get_opengl_max_aa_level(opengl_context_);
 
-    bool vsync_enabled_ = SDL_GL_GetSwapInterval() != 0;
+    bool vsync_enabled_ = sdl::GetOpenGLSwapInterval();
 
     // true if OpenGL's debug mode is enabled
     bool debug_mode_enabled_ = false;