Window API revision + Framerate limiter (#27)

- add `Backend` enum
- `GraphicsDevice` can now take a preferred backend at creation

- add `GraphicsDevice.ClaimWindow`
- add `GraphicsDevice.UnclaimWindow`
- add `GraphicsDevice.SetPresentMode`

- add `Window.Claimed`
- add `Window.SwapchainFormat`
- fix certain odd behaviors in multi-window scenarios

- rename `FramerateSettings` to `FrameLimiterSettings`
- add `Game.SetFrameLimiter`

Reviewed-on: MoonsideGames/MoonWorks#27

lib/RefreshCS

@@ -1 +1 @@
-Subproject commit 356f8e9ec2a6118b75e32d2a2ed7dbf4297aba78
+Subproject commit 330896a7be6db93b17b3b47734e449817bb30b7a

src/FrameLimiterSettings.cs

@@ -0,0 +1,22 @@
+namespace MoonWorks
+{
+	public enum FrameLimiterMode
+	{
+		Uncapped,
+		Capped
+	}
+
+	public struct FrameLimiterSettings
+	{
+		public FrameLimiterMode Mode;
+		public int Cap;
+
+		public FrameLimiterSettings(
+			FrameLimiterMode mode,
+			int cap
+		) {
+			Mode = mode;
+			Cap = cap;
+		}
+	}
+}

src/FramerateSettings.cs

@@ -1,14 +0,0 @@
-namespace MoonWorks
-{
-	public enum FramerateMode
-	{
-		Uncapped,
-		Capped
-	}
-
-	public struct FramerateSettings
-	{
-		public FramerateMode Mode;
-		public int Cap;
-	}
-}

src/Game.cs

@@ -29,23 +29,16 @@ namespace MoonWorks
 		private bool FramerateCapped = false;
 		private TimeSpan FramerateCapTimeSpan = TimeSpan.Zero;
 
-		public Window Window { get; }
 		public GraphicsDevice GraphicsDevice { get; }
 		public AudioDevice AudioDevice { get; }
 		public Inputs Inputs { get; }
 
-		private Dictionary<PresentMode, RefreshCS.Refresh.PresentMode> moonWorksToRefreshPresentMode = new Dictionary<PresentMode, RefreshCS.Refresh.PresentMode>
+		public Window MainWindow { get; }
-		{
-			{ PresentMode.Immediate, RefreshCS.Refresh.PresentMode.Immediate },
-			{ PresentMode.Mailbox, RefreshCS.Refresh.PresentMode.Mailbox },
-			{ PresentMode.FIFO, RefreshCS.Refresh.PresentMode.FIFO },
-			{ PresentMode.FIFORelaxed, RefreshCS.Refresh.PresentMode.FIFORelaxed }
-		};
 
 		public Game(
 			WindowCreateInfo windowCreateInfo,
 			PresentMode presentMode,
-			FramerateSettings framerateSettings,
+			FrameLimiterSettings frameLimiterSettings,
 			int targetTimestep = 60,
 			bool debugMode = false
 		)
@@ -53,12 +46,7 @@ namespace MoonWorks
 			Timestep = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / targetTimestep);
 			gameTimer = Stopwatch.StartNew();
 
-			FramerateCapped = framerateSettings.Mode == FramerateMode.Capped;
+			SetFrameLimiter(frameLimiterSettings);
-
-			if (FramerateCapped)
-			{
-				FramerateCapTimeSpan = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / framerateSettings.Cap);
-			}
 
 			for (int i = 0; i < previousSleepTimes.Length; i += 1)
 			{
@@ -75,14 +63,18 @@ namespace MoonWorks
 
 			Inputs = new Inputs();
 
-			Window = new Window(windowCreateInfo);
-
 			GraphicsDevice = new GraphicsDevice(
-				Window.Handle,
+				Backend.Vulkan,
-				moonWorksToRefreshPresentMode[presentMode],
 				debugMode
 			);
 
+			MainWindow = new Window(windowCreateInfo, GraphicsDevice.WindowFlags);
+
+			if (!GraphicsDevice.ClaimWindow(MainWindow, presentMode))
+			{
+				throw new System.SystemException("Could not claim window!");
+			}
+
 			AudioDevice = new AudioDevice();
 		}
 
@@ -96,12 +88,26 @@ namespace MoonWorks
 			Destroy();
 
 			AudioDevice.Dispose();
+			MainWindow.Dispose();
 			GraphicsDevice.Dispose();
-			Window.Dispose();
 
 			SDL.SDL_Quit();
 		}
 
+		public void SetFrameLimiter(FrameLimiterSettings settings)
+		{
+			FramerateCapped = settings.Mode == FrameLimiterMode.Capped;
+
+			if (FramerateCapped)
+			{
+				FramerateCapTimeSpan = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / settings.Cap);
+			}
+			else
+			{
+				FramerateCapTimeSpan = TimeSpan.Zero;
+			}
+		}
+
 		protected abstract void Update(TimeSpan delta);
 		protected abstract void Draw(double alpha);
 		protected virtual void Destroy() {}
@@ -224,7 +230,14 @@ namespace MoonWorks
 		{
 			if (evt.window.windowEvent == SDL.SDL_WindowEventID.SDL_WINDOWEVENT_SIZE_CHANGED)
 			{
-				Window.SizeChanged((uint) evt.window.data1, (uint) evt.window.data2);
+				var window = Window.Lookup(evt.window.windowID);
+				window.SizeChanged((uint) evt.window.data1, (uint) evt.window.data2);
+			}
+			else if (evt.window.windowEvent == SDL.SDL_WindowEventID.SDL_WINDOWEVENT_CLOSE)
+			{
+				var window = Window.Lookup(evt.window.windowID);
+				GraphicsDevice.UnclaimWindow(window);
+				window.Dispose();
 			}
 		}
 

src/Graphics/CommandBuffer.cs

@@ -13,15 +13,18 @@ namespace MoonWorks.Graphics
 		public IntPtr Handle { get; }
 
 		// some state for debug validation
-		GraphicsPipeline currentGraphicsPipeline = null;
+		GraphicsPipeline currentGraphicsPipeline;
-		ComputePipeline currentComputePipeline = null;
+		ComputePipeline currentComputePipeline;
-		bool renderPassActive = false;
+		bool renderPassActive;
 
 		// called from RefreshDevice
 		internal CommandBuffer(GraphicsDevice device, IntPtr handle)
 		{
 			Device = device;
 			Handle = handle;
+			currentGraphicsPipeline = null;
+			currentComputePipeline = null;
+			renderPassActive = false;
 		}
 
 		// FIXME: we can probably use the NativeMemory functions to not have to generate arrays here
@@ -815,7 +818,7 @@ namespace MoonWorks.Graphics
 			return new Texture(
 				Device,
 				texturePtr,
-				Device.GetSwapchainFormat(window),
+				window.SwapchainFormat,
 				width,
 				height
 			);

src/Graphics/GraphicsDevice.cs

@@ -8,6 +8,10 @@ namespace MoonWorks.Graphics
 	public class GraphicsDevice : IDisposable
 	{
 		public IntPtr Handle { get; }
+		public Backend Backend { get; }
+
+		private uint windowFlags;
+		public SDL2.SDL.SDL_WindowFlags WindowFlags => (SDL2.SDL.SDL_WindowFlags) windowFlags;
 
 		// Built-in video pipeline
 		private ShaderModule VideoVertexShader { get; }
@@ -19,19 +23,13 @@ namespace MoonWorks.Graphics
 		private readonly List<WeakReference<GraphicsResource>> resources = new List<WeakReference<GraphicsResource>>();
 
 		public GraphicsDevice(
-			IntPtr deviceWindowHandle,
+			Backend preferredBackend,
-			Refresh.PresentMode presentMode,
 			bool debugMode
 		)
 		{
-			var presentationParameters = new Refresh.PresentationParameters
+			Backend = (Backend) Refresh.Refresh_SelectBackend((Refresh.Backend) preferredBackend, out windowFlags);
-			{
-				deviceWindowHandle = deviceWindowHandle,
-				presentMode = presentMode
-			};
 
 			Handle = Refresh.Refresh_CreateDevice(
-				presentationParameters,
 				Conversions.BoolToByte(debugMode)
 			);
 
@@ -56,6 +54,43 @@ namespace MoonWorks.Graphics
 			);
 		}
 
+		public bool ClaimWindow(Window window, PresentMode presentMode)
+		{
+			var success = Conversions.ByteToBool(
+				Refresh.Refresh_ClaimWindow(
+					Handle,
+					window.Handle,
+					(Refresh.PresentMode) presentMode
+				)
+			);
+
+			if (success)
+			{
+				window.Claimed = true;
+				window.SwapchainFormat = GetSwapchainFormat(window);
+			}
+
+			return success;
+		}
+
+		public void UnclaimWindow(Window window)
+		{
+			Refresh.Refresh_UnclaimWindow(
+				Handle,
+				window.Handle
+			);
+			window.Claimed = false;
+		}
+
+		public void SetPresentMode(Window window, PresentMode presentMode)
+		{
+			Refresh.Refresh_SetSwapchainPresentMode(
+				Handle,
+				window.Handle,
+				(Refresh.PresentMode) presentMode
+			);
+		}
+
 		public CommandBuffer AcquireCommandBuffer()
 		{
 			return new CommandBuffer(this, Refresh.Refresh_AcquireCommandBuffer(Handle, 0));
@@ -82,7 +117,7 @@ namespace MoonWorks.Graphics
 			Refresh.Refresh_Wait(Handle);
 		}
 
-		public TextureFormat GetSwapchainFormat(Window window)
+		private TextureFormat GetSwapchainFormat(Window window)
 		{
 			return (TextureFormat) Refresh.Refresh_GetSwapchainFormat(Handle, window.Handle);
 		}

src/Graphics/RefreshEnums.cs

@@ -280,4 +280,12 @@ namespace MoonWorks.Graphics
 		FloatOpaqueWhite,
 		IntOpaqueWhite
 	}
+
+	public enum Backend
+	{
+		DontCare,
+		Vulkan,
+		PS5,
+		Invalid
+	}
 }

src/Window.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using SDL2;
 
 namespace MoonWorks
@@ -10,29 +11,32 @@ namespace MoonWorks
 		public uint Width { get; private set; }
 		public uint Height { get; private set; }
 
+		public bool Claimed { get; internal set; }
+		public MoonWorks.Graphics.TextureFormat SwapchainFormat { get; internal set; }
+
 		private bool IsDisposed;
 
-		public Window(WindowCreateInfo windowCreateInfo)
+		private static Dictionary<uint, Window> idLookup = new Dictionary<uint, Window>();
-		{
-			var windowFlags = SDL.SDL_WindowFlags.SDL_WINDOW_VULKAN;
 
+		public Window(WindowCreateInfo windowCreateInfo, SDL.SDL_WindowFlags flags)
+		{
 			if (windowCreateInfo.ScreenMode == ScreenMode.Fullscreen)
 			{
-				windowFlags |= SDL.SDL_WindowFlags.SDL_WINDOW_FULLSCREEN;
+				flags |= SDL.SDL_WindowFlags.SDL_WINDOW_FULLSCREEN;
 			}
 			else if (windowCreateInfo.ScreenMode == ScreenMode.BorderlessWindow)
 			{
-				windowFlags |= SDL.SDL_WindowFlags.SDL_WINDOW_FULLSCREEN_DESKTOP;
+				flags |= SDL.SDL_WindowFlags.SDL_WINDOW_FULLSCREEN_DESKTOP;
 			}
 
 			if (windowCreateInfo.SystemResizable)
 			{
-				windowFlags |= SDL.SDL_WindowFlags.SDL_WINDOW_RESIZABLE;
+				flags |= SDL.SDL_WindowFlags.SDL_WINDOW_RESIZABLE;
 			}
 
 			if (windowCreateInfo.StartMaximized)
 			{
-				windowFlags |= SDL.SDL_WindowFlags.SDL_WINDOW_MAXIMIZED;
+				flags |= SDL.SDL_WindowFlags.SDL_WINDOW_MAXIMIZED;
 			}
 
 			ScreenMode = windowCreateInfo.ScreenMode;
@@ -43,11 +47,13 @@ namespace MoonWorks
 				SDL.SDL_WINDOWPOS_UNDEFINED,
 				(int) windowCreateInfo.WindowWidth,
 				(int) windowCreateInfo.WindowHeight,
-				windowFlags
+				flags
 			);
 
 			Width = windowCreateInfo.WindowWidth;
 			Height = windowCreateInfo.WindowHeight;
+
+			idLookup.Add(SDL.SDL_GetWindowID(Handle), this);
 		}
 
 		public void ChangeScreenMode(ScreenMode screenMode)
@@ -81,6 +87,11 @@ namespace MoonWorks
 			Height = height;
 		}
 
+		internal static Window Lookup(uint windowID)
+		{
+			return idLookup.ContainsKey(windowID) ? idLookup[windowID] : null;
+		}
+
 		internal void SizeChanged(uint width, uint height)
 		{
 			Width = width;
@@ -96,6 +107,7 @@ namespace MoonWorks
 					// dispose managed state (managed objects)
 				}
 
+				idLookup.Remove(SDL.SDL_GetWindowID(Handle));
 				SDL.SDL_DestroyWindow(Handle);
 
 				IsDisposed = true;