Allow renderers to pick the graphics API (#96)

ultramodern/include/ultramodern/config.hpp

@@ -74,8 +74,6 @@ namespace ultramodern {
 
             virtual ~GraphicsConfig() = default;
 
-            std::string get_graphics_api_name() const;
-
             auto operator<=>(const GraphicsConfig& rhs) const = default;
         };
 
@@ -103,6 +101,7 @@ namespace ultramodern {
             {ultramodern::renderer::GraphicsApi::Auto, "Auto"},
             {ultramodern::renderer::GraphicsApi::D3D12, "D3D12"},
             {ultramodern::renderer::GraphicsApi::Vulkan, "Vulkan"},
+            {ultramodern::renderer::GraphicsApi::Metal, "Metal"},
         });
 
         NLOHMANN_JSON_SERIALIZE_ENUM(ultramodern::renderer::AspectRatio, {

ultramodern/include/ultramodern/renderer_context.hpp

@@ -62,6 +62,7 @@ namespace ultramodern {
 
                 virtual bool valid() = 0;
                 virtual SetupResult get_setup_result() const { return setup_result; }
+                virtual GraphicsApi get_chosen_api() const { return chosen_api; }
 
                 virtual bool update_config(const GraphicsConfig& old_config, const GraphicsConfig& new_config) = 0;
 
@@ -74,11 +75,12 @@ namespace ultramodern {
 
             protected:
                 SetupResult setup_result;
+                GraphicsApi chosen_api;
         };
 
         struct callbacks_t {
             using create_render_context_t = std::unique_ptr<RendererContext>(uint8_t* rdram, WindowHandle window_handle, bool developer_mode);
-            using get_graphics_api_name_t = std::string(const GraphicsConfig& config);
+            using get_graphics_api_name_t = std::string(GraphicsApi api);
 
             /**
              * Instances a subclass of RendererContext that is used to render the game.
@@ -97,7 +99,7 @@ namespace ultramodern {
 
         std::unique_ptr<RendererContext> create_render_context(uint8_t* rdram, WindowHandle window_handle, bool developer_mode);
 
-        std::string get_graphics_api_name(const GraphicsConfig& config);
+        std::string get_graphics_api_name(GraphicsApi api);
     }
 }
 

ultramodern/src/events.cpp

@@ -249,6 +249,7 @@ void ultramodern::trigger_config_action() {
 }
 
 std::atomic<ultramodern::renderer::SetupResult> renderer_setup_result = ultramodern::renderer::SetupResult::Success;
+std::atomic<ultramodern::renderer::GraphicsApi> renderer_chosen_api = ultramodern::renderer::GraphicsApi::Auto;
 
 void gfx_thread_func(uint8_t* rdram, moodycamel::LightweightSemaphore* thread_ready, ultramodern::renderer::WindowHandle window_handle) {
     bool enabled_instant_present = false;
@@ -261,6 +262,7 @@ void gfx_thread_func(uint8_t* rdram, moodycamel::LightweightSemaphore* thread_re
 
     auto renderer_context = ultramodern::renderer::create_render_context(rdram, window_handle, ultramodern::renderer::get_graphics_config().developer_mode);
 
+    renderer_chosen_api.store(renderer_context->get_chosen_api());
     if (!renderer_context->valid()) {
         renderer_setup_result.store(renderer_context->get_setup_result());
         // Notify the caller thread that this thread is ready.
@@ -534,10 +536,10 @@ void ultramodern::init_events(RDRAM_ARG ultramodern::renderer::WindowHandle wind
                 show_renderer_error("Failed to load dynamic libraries. Make sure the DLLs are next to the recomp executable.");
                 break;
             case ultramodern::renderer::SetupResult::InvalidGraphicsAPI:
-                show_renderer_error(ultramodern::renderer::get_graphics_api_name(ultramodern::renderer::get_graphics_config()) + " is not supported on this platform. Please select a different graphics API.");
+                show_renderer_error(ultramodern::renderer::get_graphics_api_name(renderer_chosen_api.load()) + " is not supported on this platform. Please select a different graphics API.");
                 break;
             case ultramodern::renderer::SetupResult::GraphicsAPINotFound:
-                show_renderer_error("Unable to initialize " + ultramodern::renderer::get_graphics_api_name(ultramodern::renderer::get_graphics_config()) + "." + driver_os_suffix);
+                show_renderer_error("Unable to initialize " + ultramodern::renderer::get_graphics_api_name(renderer_chosen_api.load()) + "." + driver_os_suffix);
                 break;
             case ultramodern::renderer::SetupResult::GraphicsDeviceNotFound:
                 show_renderer_error("Unable to find compatible graphics device." + driver_os_suffix);

ultramodern/src/renderer_context.cpp

@@ -20,11 +20,22 @@ std::unique_ptr<ultramodern::renderer::RendererContext> ultramodern::renderer::c
     return render_callbacks.create_render_context(rdram, window_handle, developer_mode);
 }
 
-std::string ultramodern::renderer::get_graphics_api_name(const GraphicsConfig& config) {
+std::string ultramodern::renderer::get_graphics_api_name(GraphicsApi api) {
     if (render_callbacks.get_graphics_api_name != nullptr) {
-        return render_callbacks.get_graphics_api_name(config);
+        return render_callbacks.get_graphics_api_name(api);
+    }
+    switch (api) {
+    case ultramodern::renderer::GraphicsApi::Auto:
+        return "Auto";
+    case ultramodern::renderer::GraphicsApi::D3D12:
+        return "D3D12";
+    case ultramodern::renderer::GraphicsApi::Vulkan:
+        return "Vulkan";
+    case ultramodern::renderer::GraphicsApi::Metal:
+        return "Metal";
+    default:
+        return "[Unknown graphics API]";
     }
-    return config.get_graphics_api_name();
 }
 
 
@@ -41,30 +52,3 @@ const ultramodern::renderer::GraphicsConfig& ultramodern::renderer::get_graphics
     std::lock_guard<std::mutex> lock(graphic_config_mutex);
     return graphic_config;
 }
-
-std::string ultramodern::renderer::GraphicsConfig::get_graphics_api_name() const {
-    ultramodern::renderer::GraphicsApi api = api_option;
-
-    if (api == ultramodern::renderer::GraphicsApi::Auto) {
-#if defined(_WIN32)
-        api = ultramodern::renderer::GraphicsApi::D3D12;
-#elif defined(__gnu_linux__)
-        api = ultramodern::renderer::GraphicsApi::Vulkan;
-#elif defined(__APPLE__)
-        api = ultramodern::renderer::GraphicsApi::Metal;
-#else
-        static_assert(false && "Unimplemented")
-#endif
-    }
-
-    switch (api) {
-        case ultramodern::renderer::GraphicsApi::D3D12:
-            return "D3D12";
-        case ultramodern::renderer::GraphicsApi::Vulkan:
-            return "Vulkan";
-        case ultramodern::renderer::GraphicsApi::Metal:
-            return "Metal";
-        default:
-            return "[Unknown graphics API]";
-    }
-}