- GZDoom now runs on an OpenGL core profile. :)

It's probably still necessary to replace GLEW with another loader library. GLEW is pretty much broken on core OpenGL without some hacky workarounds...

src/gl/system/gl_framebuffer.cpp

@@ -121,6 +121,7 @@ void OpenGLFrameBuffer::InitializeState()
 
 	if (first)
 	{
+		glewExperimental=TRUE;
 		glewInit();
 	}
 
@@ -140,7 +141,6 @@ void OpenGLFrameBuffer::InitializeState()
 	glDepthFunc(GL_LESS);
 
 	glEnable(GL_DITHER);
-	glEnable(GL_ALPHA_TEST);
 	glDisable(GL_CULL_FACE);
 	glDisable(GL_POLYGON_OFFSET_FILL);
 	glEnable(GL_POLYGON_OFFSET_LINE);

src/gl/system/gl_interface.cpp

@@ -61,24 +61,15 @@ int occlusion_type=0;
 
 static void CollectExtensions()
 {
-	const char *supported = NULL;
+	const char *extension;
-	char *extensions, *extension;
 
-	supported = (char *)glGetString(GL_EXTENSIONS);
+	int max = 0;
+	glGetIntegerv(GL_NUM_EXTENSIONS, &max);
 
-	if (supported)
+	for(int i = 0; i < max; i++)
 	{
-		extensions = new char[strlen(supported) + 1];
+		extension = (const char*)glGetStringi(GL_EXTENSIONS, i);
-		strcpy(extensions, supported);
+		m_Extensions.Push(FString(extension));
-
-		extension = strtok(extensions, " ");
-		while(extension)
-		{
-			m_Extensions.Push(FString(extension));
-			extension = strtok(NULL, " ");
-		}
-
-		delete [] extensions;
 	}
 }
 
@@ -132,14 +123,16 @@ void gl_LoadExtensions()
 	{
 		I_FatalError("Unsupported OpenGL version.\nAt least GL 3.0 is required to run " GAMENAME ".\n");
 	}
-	gl.version = strtod(version, NULL);
+
-	gl.glslversion = strtod((char*)glGetString(GL_SHADING_LANGUAGE_VERSION), NULL);
+	// add 0.01 to account for roundoff errors making the number a tad smaller than the actual version
+	gl.version = strtod(version, NULL) + 0.01f;
+	gl.glslversion = strtod((char*)glGetString(GL_SHADING_LANGUAGE_VERSION), NULL) + 0.01f;
 
 	gl.vendorstring=(char*)glGetString(GL_VENDOR);
 
 	if (CheckExtension("GL_ARB_texture_compression")) gl.flags|=RFL_TEXTURE_COMPRESSION;
 	if (CheckExtension("GL_EXT_texture_compression_s3tc")) gl.flags|=RFL_TEXTURE_COMPRESSION_S3TC;
-	if (gl.version >= 4.f && CheckExtension("GL_ARB_buffer_storage")) gl.flags |= RFL_BUFFER_STORAGE;
+	if (CheckExtension("GL_ARB_buffer_storage")) gl.flags |= RFL_BUFFER_STORAGE;
 
 	glGetIntegerv(GL_MAX_TEXTURE_SIZE,&gl.max_texturesize);
 	glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
@@ -157,11 +150,15 @@ void gl_PrintStartupLog()
 	Printf ("GL_RENDERER: %s\n", glGetString(GL_RENDERER));
 	Printf ("GL_VERSION: %s\n", glGetString(GL_VERSION));
 	Printf ("GL_SHADING_LANGUAGE_VERSION: %s\n", glGetString(GL_SHADING_LANGUAGE_VERSION));
-	Printf ("GL_EXTENSIONS: %s\n", glGetString(GL_EXTENSIONS));
+	Printf ("GL_EXTENSIONS:");
+	for (unsigned i = 0; i < m_Extensions.Size(); i++)
+	{
+		Printf(" %s", m_Extensions[i].GetChars());
+	}
 	int v;
 
 	glGetIntegerv(GL_MAX_TEXTURE_SIZE, &v);
-	Printf("Max. texture size: %d\n", v);
+	Printf("\nMax. texture size: %d\n", v);
 	glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &v);
 	Printf ("Max. texture units: %d\n", v);
 	glGetIntegerv(GL_MAX_FRAGMENT_UNIFORM_COMPONENTS, &v);

src/gl/system/gl_system.h

@@ -68,7 +68,6 @@
 
 //GL headers
 #include <GL/glew.h>
-//#include "gl_load.h"
 
 #if defined(__APPLE__)
 	#include <OpenGL/OpenGL.h>

src/win32/win32gliface.cpp

@@ -610,7 +610,7 @@ bool Win32GLVideo::SetPixelFormat()
 //
 //==========================================================================
 
-bool Win32GLVideo::SetupPixelFormat(bool allowsoftware, int multisample)
+bool Win32GLVideo::SetupPixelFormat(int multisample)
 {
 	int colorDepth;
 	HDC deskDC;
@@ -646,14 +646,7 @@ bool Win32GLVideo::SetupPixelFormat(bool allowsoftware, int multisample)
 		attributes[17]	=	true;
 	
 		attributes[18]	=	WGL_ACCELERATION_ARB;	//required to be FULL_ACCELERATION_ARB
-		if (allowsoftware)
+		attributes[19]	=	WGL_FULL_ACCELERATION_ARB;
-		{
-			attributes[19]	=	WGL_NO_ACCELERATION_ARB;
-		}
-		else
-		{
-			attributes[19]	=	WGL_FULL_ACCELERATION_ARB;
-		}
 	
 		if (multisample > 0)
 		{
@@ -713,11 +706,8 @@ bool Win32GLVideo::SetupPixelFormat(bool allowsoftware, int multisample)
 
 		if (pfd.dwFlags & PFD_GENERIC_FORMAT)
 		{
-			if (!allowsoftware)
+			Printf("R_OPENGL: OpenGL driver not accelerated!  Falling back to software renderer.\n");
-			{
+			return false;
-				Printf("R_OPENGL: OpenGL driver not accelerated!  Falling back to software renderer.\n");
-				return false;
-			}
 		}
 	}
 
@@ -735,32 +725,40 @@ bool Win32GLVideo::SetupPixelFormat(bool allowsoftware, int multisample)
 //
 //==========================================================================
 
-bool Win32GLVideo::InitHardware (HWND Window, bool allowsoftware, int multisample)
+bool Win32GLVideo::InitHardware (HWND Window, int multisample)
 {
 	m_Window=Window;
 	m_hDC = GetDC(Window);
 
-	if (!SetupPixelFormat(allowsoftware, multisample))
+	if (!SetupPixelFormat(multisample))
 	{
 		Printf ("R_OPENGL: Reverting to software mode...\n");
 		return false;
 	}
 
-	m_hRC = 0;
+	m_hRC = NULL;
 	if (myWglCreateContextAttribsARB != NULL)
 	{
-		int ctxAttribs[] = {
+		// let's try to get the best version possible.
-			WGL_CONTEXT_MAJOR_VERSION_ARB, 3,
+		static int versions[] = { 44, 43, 42, 41, 40, 33, 32, -1 };
-			WGL_CONTEXT_MINOR_VERSION_ARB, 3,
-			WGL_CONTEXT_FLAGS_ARB, gl_debug? WGL_CONTEXT_DEBUG_BIT_ARB : 0,
-			WGL_CONTEXT_PROFILE_MASK_ARB, WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB,
-			0
-		};
 
-		m_hRC = myWglCreateContextAttribsARB(m_hDC, 0, ctxAttribs);
+		for (int i = 0; versions[i] > 0; i++)
+		{
+			int ctxAttribs[] = {
+				WGL_CONTEXT_MAJOR_VERSION_ARB, versions[i] / 10,
+				WGL_CONTEXT_MINOR_VERSION_ARB, versions[i] % 10,
+				WGL_CONTEXT_FLAGS_ARB, gl_debug ? WGL_CONTEXT_DEBUG_BIT_ARB : 0,
+				WGL_CONTEXT_PROFILE_MASK_ARB, WGL_CONTEXT_CORE_PROFILE_BIT_ARB,
+				0
+			};
+
+			m_hRC = myWglCreateContextAttribsARB(m_hDC, 0, ctxAttribs);
+			if (m_hRC != NULL) break;
+		}
 	}
 	if (m_hRC == 0)
 	{
+		// If we are unable to get a core context, let's try whatever the system gives us.
 		m_hRC = wglCreateContext(m_hDC);
 	}
 
@@ -903,7 +901,7 @@ Win32GLFrameBuffer::Win32GLFrameBuffer(void *hMonitor, int width, int height, in
 		I_RestoreWindowedPos();
 	}
 
-	if (!static_cast<Win32GLVideo *>(Video)->InitHardware(Window, false, localmultisample))
+	if (!static_cast<Win32GLVideo *>(Video)->InitHardware(Window, localmultisample))
 	{
 		vid_renderer = 0;
 		return;

src/win32/win32gliface.h

@@ -42,7 +42,7 @@ public:
 	DFrameBuffer *CreateFrameBuffer (int width, int height, bool fs, DFrameBuffer *old);
 	virtual bool SetResolution (int width, int height, int bits);
 	void DumpAdapters();
-	bool InitHardware (HWND Window, bool allowsoftware, int multisample);
+	bool InitHardware (HWND Window, int multisample);
 	void Shutdown();
 	bool SetFullscreen(const char *devicename, int w, int h, int bits, int hz);
 
@@ -81,7 +81,7 @@ protected:
 	HWND InitDummy();
 	void ShutdownDummy(HWND dummy);
 	bool SetPixelFormat();
-	bool SetupPixelFormat(bool allowsoftware, int multisample);
+	bool SetupPixelFormat(int multisample);
 
 	void GetDisplayDeviceName();
 	void MakeModesList();

wadsrc/static/shaders/glsl/main.vp

@@ -22,7 +22,7 @@ void main()
 
 #ifdef UNIFORM_VB
 	
-	if (gl_MultiTexCoord0.x >= 100000.0)
+	if (aTexCoord.x >= 100000.0)
 	{
 		int fakeVI = int(aTexCoord.y)*5;
 		vert = aPosition + vec4(fakeVB[fakeVI], fakeVB[fakeVI+1], fakeVB[fakeVI+2], 0.0);