Add support for custom Video shaders

src/Graphics/GraphicsDevice.cs

@@ -22,6 +22,10 @@ namespace MoonWorks.Graphics
 
 		private readonly List<WeakReference<GraphicsResource>> resources = new List<WeakReference<GraphicsResource>>();
 
+		private static bool usingCustomVideoShaders;
+		private static string customVideoVertexShaderFilepath;
+		private static string customVideoFragmentShaderFilepath;
+
 		public GraphicsDevice(
 			Backend preferredBackend,
 			bool debugMode
@@ -38,8 +42,24 @@ namespace MoonWorks.Graphics
 				Conversions.BoolToByte(debugMode)
 			);
 
-			VideoVertexShader = new ShaderModule(this, GetEmbeddedResource("MoonWorks.Shaders.FullscreenVert.spv"));
-			VideoFragmentShader = new ShaderModule(this, GetEmbeddedResource("MoonWorks.Shaders.YUV2RGBAFrag.spv"));
+			Stream videoVertexShaderStream;
+			Stream videoFragmentShaderStream;
+			if (!usingCustomVideoShaders)
+			{
+				videoVertexShaderStream = GetEmbeddedResource("MoonWorks.Shaders.FullscreenVert.spv");
+				videoFragmentShaderStream = GetEmbeddedResource("MoonWorks.Shaders.YUV2RGBAFrag.spv");
+			}
+			else
+			{
+				videoVertexShaderStream = File.Open(customVideoVertexShaderFilepath, FileMode.Open, FileAccess.Read);
+				videoFragmentShaderStream = File.Open(customVideoFragmentShaderFilepath, FileMode.Open, FileAccess.Read);
+			}
+
+			VideoVertexShader = new ShaderModule(this, videoVertexShaderStream);
+			VideoFragmentShader = new ShaderModule(this, videoFragmentShaderStream);
+
+			videoVertexShaderStream.Close();
+			videoFragmentShaderStream.Close();
 
 			VideoPipeline = new GraphicsPipeline(
 				this,
@@ -148,6 +168,16 @@ namespace MoonWorks.Graphics
 			return typeof(GraphicsDevice).Assembly.GetManifestResourceStream(name);
 		}
 
+		/// <summary>
+		/// Use this ONLY for platforms with non-standard graphics APIs where the shader code can't be embedded into the assembly!
+		/// </summary>
+		public static void UseCustomVideoShaders(string vertexShaderFilePath, string fragmentShaderFilePath)
+		{
+			usingCustomVideoShaders = true;
+			customVideoVertexShaderFilepath = vertexShaderFilePath;
+			customVideoFragmentShaderFilepath = fragmentShaderFilePath;
+		}
+
 		protected virtual void Dispose(bool disposing)
 		{
 			if (!IsDisposed)