Avoid clearing alpha channel by handle when presenting (#2323)

* Avoid clearning alpha channel by handle when presenting

Previous code was binding then blitting while the framebuffer was bound
and then clearing the alpha channel by its handle.

This ended up triggering a bug since AMD driver 21.4.1 ending up
clearing the whole framebuffer as a result.

New code fix this weird logic by applying the clear on the bound
framebuffer.

Close #2236.

* Address rip's comments

* Fix AMD being broken once again

Ryujinx.Graphics.OpenGL/Pipeline.cs

@@ -1232,7 +1232,7 @@ namespace Ryujinx.Graphics.OpenGL
             }
         }
 
-        private void RestoreComponentMask(int index)
+        public void RestoreComponentMask(int index)
         {
             // If the bound render target is bgra, swap the red and blue masks.
             uint redMask = _fpIsBgra[index] == 0 ? 1u : 4u;

Ryujinx.Graphics.OpenGL/Window.cs

@@ -1,4 +1,3 @@
-using OpenTK.Graphics;
 using OpenTK.Graphics.OpenGL;
 using Ryujinx.Graphics.GAL;
 using Ryujinx.Graphics.OpenGL.Image;
@@ -39,12 +38,8 @@ namespace Ryujinx.Graphics.OpenGL
 
         private void CopyTextureToFrameBufferRGB(int drawFramebuffer, int readFramebuffer, TextureView view, ImageCrop crop)
         {
-            bool[] oldFramebufferColorWritemask = new bool[4];
-
             (int oldDrawFramebufferHandle, int oldReadFramebufferHandle) = ((Pipeline)_renderer.Pipeline).GetBoundFramebuffers();
 
-            GL.GetBoolean(GetIndexedPName.ColorWritemask, drawFramebuffer, oldFramebufferColorWritemask);
-
             GL.BindFramebuffer(FramebufferTarget.DrawFramebuffer, drawFramebuffer);
             GL.BindFramebuffer(FramebufferTarget.ReadFramebuffer, readFramebuffer);
 
@@ -124,13 +119,14 @@ namespace Ryujinx.Graphics.OpenGL
                 BlitFramebufferFilter.Linear);
 
             // Remove Alpha channel
-            GL.ColorMask(drawFramebuffer, false, false, false, true);
-            GL.ClearBuffer(ClearBuffer.Color, drawFramebuffer, new float[] { 0.0f, 0.0f, 0.0f, 1.0f });
-            GL.ColorMask(drawFramebuffer,
-                oldFramebufferColorWritemask[0],
-                oldFramebufferColorWritemask[1],
-                oldFramebufferColorWritemask[2],
-                oldFramebufferColorWritemask[3]);
+            GL.ColorMask(false, false, false, true);
+            GL.ClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+            GL.Clear(ClearBufferMask.ColorBufferBit);
+
+            for (int i = 0; i < Constants.MaxRenderTargets; i++)
+            {
+                ((Pipeline)_renderer.Pipeline).RestoreComponentMask(i);
+            }
 
             GL.BindFramebuffer(FramebufferTarget.ReadFramebuffer, oldReadFramebufferHandle);
             GL.BindFramebuffer(FramebufferTarget.DrawFramebuffer, oldDrawFramebufferHandle);