From 58d501f7585a02d23cd02edeb6980bf84dee688d Mon Sep 17 00:00:00 2001
From: Thog <me@thog.eu>
Date: Thu, 13 Feb 2020 16:22:48 +0100
Subject: [PATCH] Make sure to clear alpha channel when presenting Texture

This fix once and for all the transparency issue on Windows.
---
 Ryujinx.Graphics.OpenGL/Window.cs | 40 +++++++++++++++++++++----------
 Ryujinx/Ui/GLRenderer.cs          |  2 +-
 2 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/Ryujinx.Graphics.OpenGL/Window.cs b/Ryujinx.Graphics.OpenGL/Window.cs
index 26fc6a64b8..2689a7c4a6 100644
--- a/Ryujinx.Graphics.OpenGL/Window.cs
+++ b/Ryujinx.Graphics.OpenGL/Window.cs
@@ -22,15 +22,30 @@ namespace Ryujinx.Graphics.OpenGL
 
         public void Present(ITexture texture, ImageCrop crop)
         {
-            TextureView view = (TextureView)texture;
-
             GL.Disable(EnableCap.FramebufferSrgb);
 
+            CopyTextureToFrameBufferRGB(0, GetCopyFramebufferHandleLazy(), (TextureView)texture, crop);
+
+            GL.Enable(EnableCap.FramebufferSrgb);
+        }
+
+        public void SetSize(int width, int height)
+        {
+            _width  = width;
+            _height = height;
+        }
+
+
+        private void CopyTextureToFrameBufferRGB(int drawFramebuffer, int readFramebuffer, TextureView view, ImageCrop crop)
+        {
+            bool[] oldFramebufferColorWritemask = new bool[4];
+
             int oldReadFramebufferHandle = GL.GetInteger(GetPName.ReadFramebufferBinding);
             int oldDrawFramebufferHandle = GL.GetInteger(GetPName.DrawFramebufferBinding);
+            GL.GetBoolean(GetIndexedPName.ColorWritemask, drawFramebuffer, oldFramebufferColorWritemask);
 
-            GL.BindFramebuffer(FramebufferTarget.DrawFramebuffer, 0);
-            GL.BindFramebuffer(FramebufferTarget.ReadFramebuffer, GetCopyFramebufferHandleLazy());
+            GL.BindFramebuffer(FramebufferTarget.DrawFramebuffer, drawFramebuffer);
+            GL.BindFramebuffer(FramebufferTarget.ReadFramebuffer, readFramebuffer);
 
             GL.FramebufferTexture(
                 FramebufferTarget.ReadFramebuffer,
@@ -93,16 +108,17 @@ namespace Ryujinx.Graphics.OpenGL
                 ClearBufferMask.ColorBufferBit,
                 BlitFramebufferFilter.Linear);
 
+            // Remove Alpha channel
+            GL.ColorMask(drawFramebuffer, false, false, false, true);
+            GL.ClearBuffer(ClearBuffer.Color, 0, new float[] { 0.0f, 0.0f, 0.0f, 1.0f });
+            GL.ColorMask(drawFramebuffer,
+                oldFramebufferColorWritemask[0],
+                oldFramebufferColorWritemask[1],
+                oldFramebufferColorWritemask[2],
+                oldFramebufferColorWritemask[3]);
+
             GL.BindFramebuffer(FramebufferTarget.ReadFramebuffer, oldReadFramebufferHandle);
             GL.BindFramebuffer(FramebufferTarget.DrawFramebuffer, oldDrawFramebufferHandle);
-
-            GL.Enable(EnableCap.FramebufferSrgb);
-        }
-
-        public void SetSize(int width, int height)
-        {
-            _width  = width;
-            _height = height;
         }
 
         private int GetCopyFramebufferHandleLazy()
diff --git a/Ryujinx/Ui/GLRenderer.cs b/Ryujinx/Ui/GLRenderer.cs
index 0e5c7bb11f..be76fb0240 100644
--- a/Ryujinx/Ui/GLRenderer.cs
+++ b/Ryujinx/Ui/GLRenderer.cs
@@ -53,7 +53,7 @@ namespace Ryujinx.Ui
         private Input.NpadController _primaryController;
 
         public GLRenderer(Switch device) 
-            : base (new GraphicsMode(new ColorFormat(24)), 
+            : base (new GraphicsMode(new ColorFormat()),
             3, 3, 
             GraphicsContextFlags.ForwardCompatible)
         {