From bcc0d83bf0106d13484e21410beb244116a87887 Mon Sep 17 00:00:00 2001
From: CasualPokePlayer <50538166+CasualPokePlayer@users.noreply.github.com>
Date: Fri, 7 Jun 2024 23:41:13 -0700
Subject: [PATCH] Fix OpenGL shared contexts not actually being shared

---
 .../OpenGL/SDL2OpenGLContext.cs               | 21 +++++++------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/src/BizHawk.Bizware.Graphics/OpenGL/SDL2OpenGLContext.cs b/src/BizHawk.Bizware.Graphics/OpenGL/SDL2OpenGLContext.cs
index af66b7706b..6886263c5d 100644
--- a/src/BizHawk.Bizware.Graphics/OpenGL/SDL2OpenGLContext.cs
+++ b/src/BizHawk.Bizware.Graphics/OpenGL/SDL2OpenGLContext.cs
@@ -47,7 +47,7 @@ namespace BizHawk.Bizware.Graphics
 		private IntPtr _sdlWindow;
 		private IntPtr _glContext;
 
-		private void CreateContext(int majorVersion, int minorVersion, bool coreProfile)
+		private void CreateContext(int majorVersion, int minorVersion, bool coreProfile, bool shareContext)
 		{
 			// set some sensible defaults
 			SDL_GL_ResetAttributes();
@@ -86,6 +86,11 @@ namespace BizHawk.Bizware.Graphics
 				throw new($"Could not set GL profile! SDL Error: {SDL_GetError()}");
 			}
 
+			if (SDL_GL_SetAttribute(SDL_GLattr.SDL_GL_SHARE_WITH_CURRENT_CONTEXT, shareContext ? 1 : 0) != 0)
+			{
+				throw new($"Could not set share context attribute! SDL Error: {SDL_GetError()}");
+			}
+
 			_glContext = SDL_GL_CreateContext(_sdlWindow);
 			if (_glContext == IntPtr.Zero)
 			{
@@ -113,12 +118,7 @@ namespace BizHawk.Bizware.Graphics
 			}
 
 			// Controls are not shared, they are the sharees
-			if (SDL_GL_SetAttribute(SDL_GLattr.SDL_GL_SHARE_WITH_CURRENT_CONTEXT, 0) != 0)
-			{
-				throw new($"Could not set share context attribute! SDL Error: {SDL_GetError()}");
-			}
-
-			CreateContext(majorVersion, minorVersion, coreProfile);
+			CreateContext(majorVersion, minorVersion, coreProfile, shareContext: false);
 		}
 
 		public SDL2OpenGLContext(int majorVersion, int minorVersion, bool coreProfile)
@@ -132,12 +132,7 @@ namespace BizHawk.Bizware.Graphics
 
 			// offscreen contexts are shared (as we want to send texture from it over to our control's context)
 			// make sure to set the current graphics control context before creating this context
-			if (SDL_GL_SetAttribute(SDL_GLattr.SDL_GL_SHARE_WITH_CURRENT_CONTEXT, 1) != 0)
-			{
-				throw new($"Could not set share context attribute! SDL Error: {SDL_GetError()}");
-			}
-
-			CreateContext(majorVersion, minorVersion, coreProfile);
+			CreateContext(majorVersion, minorVersion, coreProfile, shareContext: true);
 		}
 
 		public void Dispose()