some prepwork for opengl texture ID importing (skip rendertarget resolve on OGL display method) but there are still problems and it can't be enabled yet

BizHawk.Client.Common/SavestateManager.cs

@@ -38,7 +38,16 @@ namespace BizHawk.Client.Common
 				{
 					var vp = Global.Emulator.VideoProvider();
 					var buff = vp.GetVideoBuffer();
-
+					if (buff.Length == 1)
+					{
+						//is a hacky opengl texture ID. can't handle this now!
+						//need to discuss options
+						//1. cores must be able to provide a pixels videoprovider in addition to a texture ID, on command (not very hard overall but interface changing and work per core)
+						//2. SavestateManager must be setup with a mechanism for resolving texture IDs (even less work, but sloppy)
+						//There are additional problems with AVWriting. They depend on VideoProvider providing pixels.
+					}
+					else
+					{
 						int out_w = vp.BufferWidth;
 						int out_h = vp.BufferHeight;
 
@@ -51,6 +60,7 @@ namespace BizHawk.Client.Common
 						using (new SimpleTime("Save Framebuffer"))
 							bs.PutLump(BinaryStateLump.Framebuffer, (s) => QuickBmpFile.Save(Global.Emulator.VideoProvider(), s, out_w, out_h));
 					}
+				}
 
 				if (Global.MovieSession.Movie.IsActive)
 				{

BizHawk.Client.EmuHawk/DisplayManager/DisplayManager.cs

@@ -348,7 +348,7 @@ namespace BizHawk.Client.EmuHawk
 		/// Then it will stuff it into the bound PresentationPanel.
 		/// ---
 		/// If the int[] is size=1, then it contains an openGL texture ID (and the size should be as specified from videoProvider)
-		/// Don't worry about the case where the frontend isnt using opengl; it isnt supported yet, and it will be my responsibility to deal with anyway
+		/// Don't worry about the case where the frontend isnt using opengl; DisplayManager deals with it
 		/// </summary>
 		public void UpdateSource(IVideoProvider videoProvider)
 		{
@@ -364,6 +364,20 @@ namespace BizHawk.Client.EmuHawk
 			UpdateSourceInternal(job);
 		}
 
+		public BitmapBuffer RenderVideoProvider(IVideoProvider videoProvider)
+		{
+			var job = new JobInfo
+			{
+				videoProvider = videoProvider,
+				simulate = false,
+				chain_outsize = new Size(videoProvider.BufferWidth, videoProvider.BufferHeight),
+				offscreen = true,
+				includeOSD = false
+			};
+			UpdateSourceInternal(job);
+			return job.offscreenBB;
+		}
+
 		public BitmapBuffer RenderOffscreen(IVideoProvider videoProvider, bool includeOSD)
 		{
 			var job = new JobInfo
@@ -653,6 +667,7 @@ namespace BizHawk.Client.EmuHawk
 			fPresent.TextureSize = new Size(bufferWidth, bufferHeight);
 			fPresent.BackgroundColor = videoProvider.BackgroundColor;
 			fPresent.GuiRenderer = Renderer;
+			fPresent.Flip = isGlTextureId;
 			fPresent.Config_FixAspectRatio = Global.Config.DispFixAspectRatio;
 			fPresent.Config_FixScaleInteger = Global.Config.DispFixScaleInteger;
 			fPresent.Padding = ClientExtraPadding;
@@ -681,7 +696,7 @@ namespace BizHawk.Client.EmuHawk
 			//begin rendering on this context
 			//should this have been done earlier?
 			//do i need to check this on an intel video card to see if running excessively is a problem? (it used to be in the FinalTarget command below, shouldnt be a problem)
-			//GraphicsControl.Begin();
+			//GraphicsControl.Begin(); //CRITICAL POINT for yabause+GL
 
 			GlobalWin.GL.BeginScene();
 
@@ -736,6 +751,7 @@ namespace BizHawk.Client.EmuHawk
 			if (job.offscreen)
 			{
 				job.offscreenBB = rtCurr.Texture2d.Resolve();
+				job.offscreenBB.DiscardAlpha();
 			}
 			else
 			{

BizHawk.Client.EmuHawk/DisplayManager/Filters/Gui.cs

@@ -178,6 +178,7 @@ namespace BizHawk.Client.EmuHawk.Filters
 		public Size TextureSize, VirtualTextureSize;
 		public int BackgroundColor;
 		public IGuiRenderer GuiRenderer;
+		public bool Flip;
 		public IGL GL;
 		bool nop;
 		LetterboxingLogic LL;
@@ -238,6 +239,8 @@ namespace BizHawk.Client.EmuHawk.Filters
 				need = true;
 			if (FilterOption != eFilterOption.None)
 				need = true;
+			if (Flip)
+				need = true;
 
 			if (!need)
 			{
@@ -318,7 +321,13 @@ namespace BizHawk.Client.EmuHawk.Filters
 			}
 
 
-			GuiRenderer.Draw(InputTexture,LL.vx,LL.vy,LL.vw,LL.vh);
+			GuiRenderer.Modelview.Translate(LL.vx, LL.vy);
+			if (Flip)
+			{
+				GuiRenderer.Modelview.Scale(1, -1);
+				GuiRenderer.Modelview.Translate(0, -LL.vh);
+			}
+			GuiRenderer.Draw(InputTexture,0,0,LL.vw,LL.vh);
 
 			GuiRenderer.End();
 		}

BizHawk.Client.EmuHawk/MainForm.cs

@@ -916,7 +916,6 @@ namespace BizHawk.Client.EmuHawk
 		{
 			using (var bb = GlobalWin.DisplayManager.RenderOffscreen(Global.Emulator.VideoProvider(), Global.Config.Screenshot_CaptureOSD))
 			{
-				bb.DiscardAlpha();
 				using (var img = bb.ToSysdrawingBitmap())
 					Clipboard.SetImage(img);
 			}
@@ -1895,11 +1894,9 @@ namespace BizHawk.Client.EmuHawk
 			}
 		}
 
-		private static unsafe BitmapBuffer MakeScreenshotImage()
+		private static BitmapBuffer MakeScreenshotImage()
 		{
-			var bb = new BitmapBuffer(Global.Emulator.VideoProvider().BufferWidth, Global.Emulator.VideoProvider().BufferHeight, Global.Emulator.VideoProvider().GetVideoBuffer());
+			return GlobalWin.DisplayManager.RenderVideoProvider(Global.Emulator.VideoProvider());
-			bb.DiscardAlpha();
-			return bb;
 		}
 
 		private void SaveSlotSelectedMessage()

BizHawk.Client.EmuHawk/Program.cs

@@ -127,7 +127,7 @@ namespace BizHawk.Client.EmuHawk
 			GlobalWin.IGL_GL = new Bizware.BizwareGL.Drivers.OpenTK.IGL_TK(2,0,false);
 
 			//setup the GL context manager, needed for coping with multiple opengl cores vs opengl display method
-			GLManager.CreateInstance();
+			GLManager.CreateInstance(GlobalWin.IGL_GL);
 			GlobalWin.GLManager = GLManager.Instance;
 			GlobalWin.CR_GL = GlobalWin.GLManager.GetContextForIGL(GlobalWin.GL);
 

BizHawk.Emulation.Cores/Consoles/Sega/Saturn/Yabause.cs

@@ -86,7 +86,7 @@ namespace BizHawk.Emulation.Cores.Sega.Saturn
 
 		public IEmulatorServiceProvider ServiceProvider { get; private set; }
 
-		static object glContext;
+		object glContext;
 
 		void ActivateGL()
 		{
@@ -329,7 +329,14 @@ namespace BizHawk.Emulation.Cores.Sega.Saturn
 		#region IVideoProvider
 
 		int[] VideoBuffer = new int[704 * 512];
-		public int[] GetVideoBuffer() { return VideoBuffer; }
+		int[] TextureIdBuffer = new int[1]; //todo
+		public int[] GetVideoBuffer() {
+			//doesn't work yet
+			//if (SyncSettings.UseGL)
+			//  return new[] { VideoBuffer[0] };
+			//else
+				return VideoBuffer;
+		}
 		public int VirtualWidth { get { return BufferWidth; } }
 		public int VirtualHeight { get { return BufferHeight; } }
 		public int BufferWidth { get; private set; }

Bizware/BizHawk.Bizware.BizwareGL.OpenTK/IGL_TK.cs

@@ -23,6 +23,7 @@ using BizHawk.Bizware.BizwareGL;
 using OpenTK;
 using OpenTK.Graphics;
 using OpenTK.Graphics.OpenGL;
+using otkg = OpenTK.Graphics;
 
 namespace BizHawk.Bizware.BizwareGL.Drivers.OpenTK
 {
@@ -496,7 +497,7 @@ namespace BizHawk.Bizware.BizwareGL.Drivers.OpenTK
 
 		public Texture2d WrapGLTexture2d(IntPtr glTexId, int width, int height)
 		{
-			return new Texture2d(this as IGL, glTexId, width, height);
+			return new Texture2d(this as IGL, glTexId.ToInt32(), width, height);
 		}
 
 		public void LoadTextureData(Texture2d tex, BitmapBuffer bmp)
@@ -590,6 +591,7 @@ namespace BizHawk.Bizware.BizwareGL.Drivers.OpenTK
 			var bb = new BitmapBuffer(tex.IntWidth, tex.IntHeight);
 			var bmpdata = bb.LockBits();
 			GL.GetTexImage(TextureTarget.Texture2D, 0, PixelFormat.Bgra, PixelType.UnsignedByte, bmpdata.Scan0);
+			var err = GL.GetError();
 			bb.UnlockBits(bmpdata);
 			return bb;
 		}

Bizware/BizHawk.Bizware.BizwareGL/IGuiRenderer.cs

@@ -35,8 +35,11 @@ namespace BizHawk.Bizware.BizwareGL
 		/// draws the specified Art resource with the specified offset, with the specified size. This could be tricky if youve applied other rotate or scale transforms first.
 		/// </summary>
 		void Draw(Art art, float x, float y, float width, float height);
-		void Draw(Texture2d art, float x, float y, float width, float height);
 
+		/// <summary>
+		/// draws the specified Texture with the specified offset, with the specified size. This could be tricky if youve applied other rotate or scale transforms first.
+		/// </summary>
+		void Draw(Texture2d art, float x, float y, float width, float height);
 
 		/// <summary>
 		/// draws the specified texture2d resource.

yabause/src/libyabause/libyabause.vcxproj

@@ -52,6 +52,7 @@
       <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;LIBYABAUSE_EXPORTS;HAVE_C99_VARIADIC_MACROS;VERSION="LIB";C68K_NO_JUMP_TABLE;HAVE_LIBGL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <DisableSpecificWarnings>4244;4996;4018;4146</DisableSpecificWarnings>
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
+      <MinimalRebuild>false</MinimalRebuild>
     </ClCompile>
     <Link>
       <SubSystem>Windows</SubSystem>

yabause/src/libyabause/yui.cpp

@@ -280,6 +280,7 @@ PerPad_struct *ctrl2;
 
 extern "C" int vdp2height;
 extern "C" int vdp2width;
+extern "C" GLuint FboTexture;
 
 /* Tells the yui to exchange front and back video buffers. This may end
    up being moved to the Video Core. */
@@ -305,6 +306,10 @@ void YuiSwapBuffers(void)
 		}
 		else
 		{
+			#ifdef CAN_RETURN_TEXTURE_IDS
+				//simply write the FboTexture into the videobuffer for later magic detection in frontend
+				memcpy(vidbuff,&FboTexture,4);
+			#else
 				glReadPixels(0, 0, glwidth, glheight, GL_BGRA, GL_UNSIGNED_BYTE, glbuff);
 
 				u32 *src = (u32*)glbuff;
@@ -318,6 +323,7 @@ void YuiSwapBuffers(void)
 					src += glwidth;
 					dst -= glwidth;
 				}
+			#endif
 		}
 	}
 }

yabause/src/ygl.c

@@ -57,6 +57,7 @@ extern int vdp1cog;
 extern int vdp1cob;
 
 GLuint DefaultFrameBuffer;
+GLuint FboTexture, MainFbo;
 
 #ifdef HAVE_GLXGETPROCADDRESS
 void STDCALL * (*yglGetProcAddress)(const char *szProcName) = (void STDCALL *(*)(const char *))glXGetProcAddress;
@@ -563,6 +564,26 @@ int YglGLInit(int width, int height) {
    glBindFramebuffer(GL_FRAMEBUFFER, DefaultFrameBuffer);
    glBindTexture(GL_TEXTURE_2D,_Ygl->texture);
 
+
+		//bizhawk code: create a texture for reading from the main FBO
+		//if the alternate 'main' FBO isn't created yet, now's the time
+		if(MainFbo == 0)
+		{
+			glGenFramebuffers(1,&MainFbo);
+			glBindFramebuffer(GL_FRAMEBUFFER, MainFbo);
+			DefaultFrameBuffer = MainFbo;
+		}
+
+		//delete existing texture if we already have it
+    if( FboTexture != 0 ) glDeleteTextures(1,&FboTexture);
+		glGenTextures(1, &FboTexture);
+		glBindTexture(GL_TEXTURE_2D, FboTexture);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, GlWidth, GlHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE,NULL);
+		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, FboTexture, 0);
+		glBindTexture(GL_TEXTURE_2D, 0);
+   
    return 0;
 }