Support for high precision framebuffers and dither noise (RT64)

From Zelda64Recomp/Zelda64Recomp#252 commit 23eb6b7eea9fd12f93d31c313faa335245bbfb3c

Co-authored-by: Mr-Wiseguy <mrwiseguyromhacking@gmail.com>

rt64

@@ -1 +1 @@
-Subproject commit ca26fb8096b9af117c668e8dfaa49fdde815c3b7
+Subproject commit 64b9e166f75b4dc44a59983b67c3e9ecc1f4cfd7

ultramodern/include/ultramodern/config.hpp

@@ -28,6 +28,12 @@ namespace ultramodern {
 		Vulkan,
 		OptionCount
 	};
+	enum class HighPrecisionFramebuffer {
+		Auto,
+		On,
+		Off,
+		OptionCount
+	};
 
 	struct GraphicsConfig {
 		Resolution res_option;
@@ -38,6 +44,7 @@ namespace ultramodern {
 		RT64::UserConfiguration::AspectRatio ar_option;
 		RT64::UserConfiguration::Antialiasing msaa_option;
 		RT64::UserConfiguration::RefreshRate rr_option;
+		HighPrecisionFramebuffer hpfb_option;
 		int rr_manual_value;
 		int ds_option;
 		bool developer_mode;
@@ -70,6 +77,12 @@ namespace ultramodern {
 		{ultramodern::GraphicsApi::D3D12, "D3D12"},
 		{ultramodern::GraphicsApi::Vulkan, "Vulkan"},
 	});
+
+	NLOHMANN_JSON_SERIALIZE_ENUM(ultramodern::HighPrecisionFramebuffer, {
+		{ultramodern::HighPrecisionFramebuffer::Auto, "Auto"},
+		{ultramodern::HighPrecisionFramebuffer::On, "On"},
+		{ultramodern::HighPrecisionFramebuffer::Off, "Off"},
+	});
 };
 
 #endif

ultramodern/include/ultramodern/rt64_layer.h

@@ -32,6 +32,7 @@ namespace ultramodern {
             void shutdown();
             void set_dummy_vi();
             uint32_t get_display_framerate();
+            float get_resolution_scale();
             void load_shader_cache(std::span<const char> cache_binary);
         private:
             RT64SetupResult setup_result;
@@ -40,6 +41,7 @@ namespace ultramodern {
 
     RT64::UserConfiguration::Antialiasing RT64MaxMSAA();
     bool RT64SamplePositionsSupported();
+    bool RT64HighPrecisionFBEnabled();
 }
 
 void set_rt64_hooks();

ultramodern/include/ultramodern/ultramodern.hpp

@@ -122,9 +122,9 @@ void sleep_milliseconds(uint32_t millis);
 void sleep_until(const std::chrono::high_resolution_clock::time_point& time_point);
 
 // Graphics
-void get_window_size(uint32_t& width, uint32_t& height);
 uint32_t get_target_framerate(uint32_t original);
 uint32_t get_display_refresh_rate();
+float get_resolution_scale();
 void load_shader_cache(std::span<const char> cache_data);
 
 // Audio

ultramodern/src/events.cpp

@@ -241,6 +241,7 @@ ultramodern::GraphicsConfig ultramodern::get_graphics_config() {
 }
 
 std::atomic_uint32_t display_refresh_rate = 60;
+std::atomic<float> resolution_scale = 1.0f;
 
 uint32_t ultramodern::get_target_framerate(uint32_t original) {
     ultramodern::GraphicsConfig graphics_config = ultramodern::get_graphics_config();
@@ -260,6 +261,10 @@ uint32_t ultramodern::get_display_refresh_rate() {
     return display_refresh_rate.load();
 }
 
+float ultramodern::get_resolution_scale() {
+    return resolution_scale.load();
+}
+
 void ultramodern::load_shader_cache(std::span<const char> cache_data) {
     events_context.action_queue.enqueue(LoadShaderCacheAction{cache_data});
 }
@@ -322,6 +327,7 @@ void gfx_thread_func(uint8_t* rdram, moodycamel::LightweightSemaphore* thread_re
                 events_context.vi.current_buffer = events_context.vi.next_buffer;
                 rt64.update_screen(swap_action->origin);
                 display_refresh_rate = rt64.get_display_framerate();
+                resolution_scale = rt64.get_resolution_scale();
             }
             else if (const auto* config_action = std::get_if<UpdateConfigAction>(&action)) {
                 ultramodern::GraphicsConfig new_config = cur_config;

ultramodern/src/rt64_layer.cpp

@@ -11,6 +11,7 @@ ultramodern::RT64Context::~RT64Context() = default;
 
 static RT64::UserConfiguration::Antialiasing device_max_msaa = RT64::UserConfiguration::Antialiasing::None;
 static bool sample_positions_supported = false;
+static bool high_precision_fb_enabled = false;
 
 static uint8_t DMEM[0x1000];
 static uint8_t IMEM[0x1000];
@@ -58,6 +59,19 @@ RT64::UserConfiguration::Antialiasing compute_max_supported_aa(RT64::RenderSampl
     return RT64::UserConfiguration::Antialiasing::None;
 }
 
+RT64::UserConfiguration::InternalColorFormat to_rt64(ultramodern::HighPrecisionFramebuffer option) {
+    switch (option) {
+        case ultramodern::HighPrecisionFramebuffer::Off:
+            return RT64::UserConfiguration::InternalColorFormat::Standard;
+        case ultramodern::HighPrecisionFramebuffer::On:
+            return RT64::UserConfiguration::InternalColorFormat::High;
+        case ultramodern::HighPrecisionFramebuffer::Auto:
+            return RT64::UserConfiguration::InternalColorFormat::Automatic;
+        default:
+            return RT64::UserConfiguration::InternalColorFormat::OptionCount;
+    }
+}
+
 void set_application_user_config(RT64::Application* application, const ultramodern::GraphicsConfig& config) {
     switch (config.res_option) {
         default:
@@ -95,6 +109,7 @@ void set_application_user_config(RT64::Application* application, const ultramode
     application->userConfig.antialiasing = config.msaa_option;
     application->userConfig.refreshRate = config.rr_option;
     application->userConfig.refreshRateTarget = config.rr_manual_value;
+    application->userConfig.internalColorFormat = to_rt64(config.hpfb_option);
 }
 
 ultramodern::RT64SetupResult map_setup_result(RT64::Application::SetupResult rt64_result) {
@@ -223,6 +238,8 @@ ultramodern::RT64Context::RT64Context(uint8_t* rdram, ultramodern::WindowHandle
         device_max_msaa = RT64::UserConfiguration::Antialiasing::None;
         sample_positions_supported = false;
     }
+
+    high_precision_fb_enabled = app->shaderLibrary->usesHDR;
 }
 
 void ultramodern::RT64Context::send_dl(const OSTask* task) {
@@ -268,6 +285,24 @@ uint32_t ultramodern::RT64Context::get_display_framerate() {
     return app->presentQueue->ext.sharedResources->swapChainRate;
 }
 
+float ultramodern::RT64Context::get_resolution_scale() {
+    constexpr int ReferenceHeight = 240;
+    switch (app->userConfig.resolution) {
+        case RT64::UserConfiguration::Resolution::WindowIntegerScale:
+            if (app->sharedQueueResources->swapChainHeight > 0) {
+                return std::max(float((app->sharedQueueResources->swapChainHeight + ReferenceHeight - 1) / ReferenceHeight), 1.0f);
+            }
+            else {
+                return 1.0f;
+            }
+        case RT64::UserConfiguration::Resolution::Manual:
+            return float(app->userConfig.resolutionMultiplier);
+        case RT64::UserConfiguration::Resolution::Original:
+        default:
+            return 1.0f;
+    }
+}
+
 void ultramodern::RT64Context::load_shader_cache(std::span<const char> cache_binary) {
     // TODO figure out how to avoid a copy here.
     std::istringstream cache_stream{std::string{cache_binary.data(), cache_binary.size()}};
@@ -285,3 +320,7 @@ RT64::UserConfiguration::Antialiasing ultramodern::RT64MaxMSAA() {
 bool ultramodern::RT64SamplePositionsSupported() {
     return sample_positions_supported;
 }
+
+bool ultramodern::RT64HighPrecisionFBEnabled() {
+    return high_precision_fb_enabled;
+}