# HG changeset patch
# User Sam Lantinga <slouken@libsdl.org>
# Date 1184132619 0
# Node ID f9d0b64cc7b944cf2acc88c55f637ec21117f5ec
# Parent  1c291c47cf1ee1ea2aa343a47994c3d12d8b7e2f
I think this fixes bug #261

Make sure that you don't use a wgl function after the context is deleted.

diff -r 1c291c47cf1e -r f9d0b64cc7b9 src/video/wincommon/SDL_wingl.c
--- a/src/video/wincommon/SDL_wingl.c	Tue Jul 10 20:15:31 2007 +0000
+++ b/src/video/wincommon/SDL_wingl.c	Wed Jul 11 05:43:39 2007 +0000
@@ -109,15 +109,16 @@
 	return 0;
 }
 
-static void Init_WGL_ARB_extensions(_THIS)
+static int ChoosePixelFormatARB(_THIS, const int *iAttribs, const FLOAT *fAttribs)
 {
 	HWND hwnd;
 	HDC hdc;
 	HGLRC hglrc;
-	int pformat;
 	const char * (WINAPI *wglGetExtensionsStringARB)(HDC) = 0;
 	const char *extensions;
-	
+	int pformat = 0;
+	UINT matches = 0;
+
 	hwnd = CreateWindow(SDL_Appname, SDL_Appname, WS_POPUP | WS_DISABLED,
 	                    0, 0, 10, 10,
 	                    NULL, NULL, SDL_Instance, NULL);
@@ -125,8 +126,7 @@
 
 	hdc = GetDC(hwnd);
 
-	pformat = ChoosePixelFormat(hdc, &GL_pfd);
-	SetPixelFormat(hdc, pformat, &GL_pfd);
+	SetPixelFormat(hdc, ChoosePixelFormat(hdc, &GL_pfd), &GL_pfd);
 
 	hglrc = this->gl_data->wglCreateContext(hdc);
 	if ( hglrc ) {
@@ -144,15 +144,12 @@
 
 	this->gl_data->WGL_ARB_pixel_format = 0;
 	if( ExtensionSupported("WGL_ARB_pixel_format", extensions) ) {
-		this->gl_data->wglChoosePixelFormatARB =
+		BOOL (WINAPI *wglChoosePixelFormatARB)(HDC hdc, const int *piAttribIList, const FLOAT *pfAttribFList, UINT nMaxFormats, int *piFormats, UINT *nNumFormats);
+		wglChoosePixelFormatARB =
 			(BOOL (WINAPI *)(HDC, const int *, const FLOAT *, UINT, int *, UINT *))
 			this->gl_data->wglGetProcAddress("wglChoosePixelFormatARB");
-		this->gl_data->wglGetPixelFormatAttribivARB =
-			(BOOL (WINAPI *)(HDC, int, int, UINT, const int *, int *))
-			this->gl_data->wglGetProcAddress("wglGetPixelFormatAttribivARB");
-
-		if( (this->gl_data->wglChoosePixelFormatARB != NULL) &&
-		    (this->gl_data->wglGetPixelFormatAttribivARB != NULL) ) {
+		if( wglChoosePixelFormatARB &&
+		    wglChoosePixelFormatARB(hdc, iAttribs, fAttribs, 1, &pformat, &matches) && pformat ) {
 			this->gl_data->WGL_ARB_pixel_format = 1;
 		}
 	}
@@ -164,6 +161,8 @@
 	ReleaseDC(hwnd, hdc);
 	DestroyWindow(hwnd);
 	WIN_FlushMessageQueue();
+
+	return pformat;
 }
 
 #endif /* SDL_VIDEO_OPENGL */
@@ -188,6 +187,105 @@
 		}
 	}
 
+	/* Set up the pixel format descriptor with our needed format */
+	SDL_memset(&GL_pfd, 0, sizeof(GL_pfd));
+	GL_pfd.nSize = sizeof(GL_pfd);
+	GL_pfd.nVersion = 1;
+	GL_pfd.dwFlags = (PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL);
+	if ( this->gl_config.double_buffer ) {
+		GL_pfd.dwFlags |= PFD_DOUBLEBUFFER;
+	}
+	if ( this->gl_config.stereo ) {
+		GL_pfd.dwFlags |= PFD_STEREO;
+	}
+	GL_pfd.iPixelType = PFD_TYPE_RGBA;
+	GL_pfd.cColorBits = this->gl_config.buffer_size;
+	GL_pfd.cRedBits = this->gl_config.red_size;
+	GL_pfd.cGreenBits = this->gl_config.green_size;
+	GL_pfd.cBlueBits = this->gl_config.blue_size;
+	GL_pfd.cAlphaBits = this->gl_config.alpha_size;
+	GL_pfd.cAccumRedBits = this->gl_config.accum_red_size;
+	GL_pfd.cAccumGreenBits = this->gl_config.accum_green_size;
+	GL_pfd.cAccumBlueBits = this->gl_config.accum_blue_size;
+	GL_pfd.cAccumAlphaBits = this->gl_config.accum_alpha_size;
+	GL_pfd.cAccumBits =
+		(GL_pfd.cAccumRedBits + GL_pfd.cAccumGreenBits +
+		 GL_pfd.cAccumBlueBits + GL_pfd.cAccumAlphaBits);
+	GL_pfd.cDepthBits = this->gl_config.depth_size;
+	GL_pfd.cStencilBits = this->gl_config.stencil_size;
+
+	/* setup WGL_ARB_pixel_format attribs */
+	iAttr = &iAttribs[0];
+
+	*iAttr++ = WGL_DRAW_TO_WINDOW_ARB;
+	*iAttr++ = GL_TRUE;
+	*iAttr++ = WGL_ACCELERATION_ARB;
+	*iAttr++ = WGL_FULL_ACCELERATION_ARB;
+	*iAttr++ = WGL_RED_BITS_ARB;
+	*iAttr++ = this->gl_config.red_size;
+	*iAttr++ = WGL_GREEN_BITS_ARB;
+	*iAttr++ = this->gl_config.green_size;
+	*iAttr++ = WGL_BLUE_BITS_ARB;
+	*iAttr++ = this->gl_config.blue_size;
+	
+	if ( this->gl_config.alpha_size ) {
+		*iAttr++ = WGL_ALPHA_BITS_ARB;
+		*iAttr++ = this->gl_config.alpha_size;
+	}
+
+	*iAttr++ = WGL_DOUBLE_BUFFER_ARB;
+	*iAttr++ = this->gl_config.double_buffer;
+
+	*iAttr++ = WGL_DEPTH_BITS_ARB;
+	*iAttr++ = this->gl_config.depth_size;
+
+	if ( this->gl_config.stencil_size ) {
+		*iAttr++ = WGL_STENCIL_BITS_ARB;
+		*iAttr++ = this->gl_config.stencil_size;
+	}
+
+	if ( this->gl_config.accum_red_size ) {
+		*iAttr++ = WGL_ACCUM_RED_BITS_ARB;
+		*iAttr++ = this->gl_config.accum_red_size;
+	}
+
+	if ( this->gl_config.accum_green_size ) {
+		*iAttr++ = WGL_ACCUM_GREEN_BITS_ARB;
+		*iAttr++ = this->gl_config.accum_green_size;
+	}
+
+	if ( this->gl_config.accum_blue_size ) {
+		*iAttr++ = WGL_ACCUM_BLUE_BITS_ARB;
+		*iAttr++ = this->gl_config.accum_blue_size;
+	}
+
+	if ( this->gl_config.accum_alpha_size ) {
+		*iAttr++ = WGL_ACCUM_ALPHA_BITS_ARB;
+		*iAttr++ = this->gl_config.accum_alpha_size;
+	}
+
+	if ( this->gl_config.stereo ) {
+		*iAttr++ = WGL_STEREO_ARB;
+		*iAttr++ = GL_TRUE;
+	}
+
+	if ( this->gl_config.multisamplebuffers ) {
+		*iAttr++ = WGL_SAMPLE_BUFFERS_ARB;
+		*iAttr++ = this->gl_config.multisamplebuffers;
+	}
+
+	if ( this->gl_config.multisamplesamples ) {
+		*iAttr++ = WGL_SAMPLES_ARB;
+		*iAttr++ = this->gl_config.multisamplesamples;
+	}
+
+	if ( this->gl_config.accelerated >= 0 ) {
+		*iAttr++ = WGL_ACCELERATION_ARB;
+		*iAttr++ = (this->gl_config.accelerated ? WGL_GENERIC_ACCELERATION_ARB : WGL_NO_ACCELERATION_ARB);
+	}
+
+	*iAttr = 0;
+
 	for ( i=0; ; ++i ) {
 		/* Get the window device context for our OpenGL drawing */
 		GL_hdc = GetDC(SDL_Window);
@@ -196,114 +294,10 @@
 			return(-1);
 		}
 
-		/* Set up the pixel format descriptor with our needed format */
-		SDL_memset(&GL_pfd, 0, sizeof(GL_pfd));
-		GL_pfd.nSize = sizeof(GL_pfd);
-		GL_pfd.nVersion = 1;
-		GL_pfd.dwFlags = (PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL);
-		if ( this->gl_config.double_buffer ) {
-			GL_pfd.dwFlags |= PFD_DOUBLEBUFFER;
-		}
-		if ( this->gl_config.stereo ) {
-			GL_pfd.dwFlags |= PFD_STEREO;
-		}
-		GL_pfd.iPixelType = PFD_TYPE_RGBA;
-		GL_pfd.cColorBits = this->gl_config.buffer_size;
-		GL_pfd.cRedBits = this->gl_config.red_size;
-		GL_pfd.cGreenBits = this->gl_config.green_size;
-		GL_pfd.cBlueBits = this->gl_config.blue_size;
-		GL_pfd.cAlphaBits = this->gl_config.alpha_size;
-		GL_pfd.cAccumRedBits = this->gl_config.accum_red_size;
-		GL_pfd.cAccumGreenBits = this->gl_config.accum_green_size;
-		GL_pfd.cAccumBlueBits = this->gl_config.accum_blue_size;
-		GL_pfd.cAccumAlphaBits = this->gl_config.accum_alpha_size;
-		GL_pfd.cAccumBits =
-			(GL_pfd.cAccumRedBits + GL_pfd.cAccumGreenBits +
-			 GL_pfd.cAccumBlueBits + GL_pfd.cAccumAlphaBits);
-		GL_pfd.cDepthBits = this->gl_config.depth_size;
-		GL_pfd.cStencilBits = this->gl_config.stencil_size;
-
-		/* initialize WGL_ARB_pixel_format */
-		Init_WGL_ARB_extensions(this);
-
-		/* setup WGL_ARB_pixel_format attribs */
-		iAttr = &iAttribs[0];
-
-		*iAttr++ = WGL_DRAW_TO_WINDOW_ARB;
-		*iAttr++ = GL_TRUE;
-		*iAttr++ = WGL_ACCELERATION_ARB;
-		*iAttr++ = WGL_FULL_ACCELERATION_ARB;
-		*iAttr++ = WGL_RED_BITS_ARB;
-		*iAttr++ = this->gl_config.red_size;
-		*iAttr++ = WGL_GREEN_BITS_ARB;
-		*iAttr++ = this->gl_config.green_size;
-		*iAttr++ = WGL_BLUE_BITS_ARB;
-		*iAttr++ = this->gl_config.blue_size;
-		
-		if ( this->gl_config.alpha_size ) {
-			*iAttr++ = WGL_ALPHA_BITS_ARB;
-			*iAttr++ = this->gl_config.alpha_size;
-		}
-
-		*iAttr++ = WGL_DOUBLE_BUFFER_ARB;
-		*iAttr++ = this->gl_config.double_buffer;
-
-		*iAttr++ = WGL_DEPTH_BITS_ARB;
-		*iAttr++ = this->gl_config.depth_size;
-
-		if ( this->gl_config.stencil_size ) {
-			*iAttr++ = WGL_STENCIL_BITS_ARB;
-			*iAttr++ = this->gl_config.stencil_size;
-		}
-
-		if ( this->gl_config.accum_red_size ) {
-			*iAttr++ = WGL_ACCUM_RED_BITS_ARB;
-			*iAttr++ = this->gl_config.accum_red_size;
-		}
-
-		if ( this->gl_config.accum_green_size ) {
-			*iAttr++ = WGL_ACCUM_GREEN_BITS_ARB;
-			*iAttr++ = this->gl_config.accum_green_size;
-		}
-
-		if ( this->gl_config.accum_blue_size ) {
-			*iAttr++ = WGL_ACCUM_BLUE_BITS_ARB;
-			*iAttr++ = this->gl_config.accum_blue_size;
-		}
-
-		if ( this->gl_config.accum_alpha_size ) {
-			*iAttr++ = WGL_ACCUM_ALPHA_BITS_ARB;
-			*iAttr++ = this->gl_config.accum_alpha_size;
-		}
-
-		if ( this->gl_config.stereo ) {
-			*iAttr++ = WGL_STEREO_ARB;
-			*iAttr++ = GL_TRUE;
-		}
-
-		if ( this->gl_config.multisamplebuffers ) {
-			*iAttr++ = WGL_SAMPLE_BUFFERS_ARB;
-			*iAttr++ = this->gl_config.multisamplebuffers;
-		}
-
-		if ( this->gl_config.multisamplesamples ) {
-			*iAttr++ = WGL_SAMPLES_ARB;
-			*iAttr++ = this->gl_config.multisamplesamples;
-		}
-
-		if ( this->gl_config.accelerated >= 0 ) {
-			*iAttr++ = WGL_ACCELERATION_ARB;
-			*iAttr++ = (this->gl_config.accelerated ? WGL_GENERIC_ACCELERATION_ARB : WGL_NO_ACCELERATION_ARB);
-		}
-
-		*iAttr = 0;
-
 		/* Choose and set the closest available pixel format */
-		if ( !this->gl_data->WGL_ARB_pixel_format ||
-		     !this->gl_data->wglChoosePixelFormatARB(GL_hdc, iAttribs, fAttribs, 1, &pixel_format, &matching) ||
-		     !matching ) {
+		pixel_format = ChoosePixelFormatARB(this, iAttribs, fAttribs);
+		if ( !pixel_format ) {
 			pixel_format = ChoosePixelFormat(GL_hdc, &GL_pfd);
-			this->gl_data->WGL_ARB_pixel_format = 0;
 		}
 		if ( !pixel_format ) {
 			SDL_SetError("No matching GL pixel format available");
@@ -335,6 +329,15 @@
 	}
 	gl_active = 1;
 
+	/* Get the wglGetPixelFormatAttribivARB pointer for the context */
+	if ( this->gl_data->WGL_ARB_pixel_format ) {
+		this->gl_data->wglGetPixelFormatAttribivARB =
+			(BOOL (WINAPI *)(HDC, int, int, UINT, const int *, int *))
+			this->gl_data->wglGetProcAddress("wglGetPixelFormatAttribivARB");
+	} else {
+		this->gl_data->wglGetPixelFormatAttribivARB = NULL;
+	}
+
 	/* Vsync control under Windows.  Checking glGetString here is
 	 * somewhat a documented and reliable hack - it was originally
 	 * as a feature added by mistake, but since so many people rely
@@ -416,7 +419,7 @@
 		return -1;
 	}
 
-	if ( this->gl_data->WGL_ARB_pixel_format ) {
+	if ( this->gl_data->wglGetPixelFormatAttribivARB ) {
 		int wgl_attrib;
 
 		switch(attrib) {
@@ -566,7 +569,6 @@
 		this->gl_data->wglCreateContext = NULL;
 		this->gl_data->wglDeleteContext = NULL;
 		this->gl_data->wglMakeCurrent = NULL;
-		this->gl_data->wglChoosePixelFormatARB = NULL;
 		this->gl_data->wglGetPixelFormatAttribivARB = NULL;
 		this->gl_data->wglSwapIntervalEXT = NULL;
 		this->gl_data->wglGetSwapIntervalEXT = NULL;
diff -r 1c291c47cf1e -r f9d0b64cc7b9 src/video/wincommon/SDL_wingl_c.h
--- a/src/video/wincommon/SDL_wingl_c.h	Tue Jul 10 20:15:31 2007 +0000
+++ b/src/video/wincommon/SDL_wingl_c.h	Wed Jul 11 05:43:39 2007 +0000
@@ -44,10 +44,6 @@
 
     BOOL (WINAPI *wglMakeCurrent)(HDC hdc, HGLRC hglrc);
    
-    BOOL (WINAPI *wglChoosePixelFormatARB)(HDC hdc, const int *piAttribIList,
-                                           const FLOAT *pfAttribFList,
-                                           UINT nMaxFormats, int *piFormats,
-                                           UINT *nNumFormats);
     BOOL (WINAPI *wglGetPixelFormatAttribivARB)(HDC hdc, int iPixelFormat,
                                                 int iLayerPlane,
                                                 UINT nAttributes,