Removes static linking of OpenGL library.

Tested By: Langbart, Stan
Differential Revision: https://code.wildfiregames.com/D4387
This was SVN commit r26104.

build/premake/extern_libs5.lua

@@ -579,35 +579,6 @@ extern_lib_defs = {
 			end
 		end,
 	},
-	opengl = {
-		compile_settings = function()
-			if os.istarget("windows") then
-				add_default_include_paths("opengl")
-			elseif _OPTIONS["gles"] then
-				pkgconfig.add_includes("glesv2")
-			elseif not os.istarget("macosx") then
-				pkgconfig.add_includes("gl")
-			end
-		end,
-		link_settings = function()
-			if os.istarget("windows") then
-				add_default_lib_paths("opengl")
-				add_default_links({
-					win_names  = { "opengl32", "gdi32" },
-					dbg_suffix = "",
-					no_delayload = 1, -- delayload seems to cause errors on startup
-				})
-			elseif os.istarget("macosx") then
-				add_default_links({
-					osx_frameworks = { "OpenGL" },
-				})
-			elseif _OPTIONS["gles"] then
-				pkgconfig.add_links("glesv2")
-			else
-				pkgconfig.add_links("gl")
-			end
-		end,
-	},
 	sdl = {
 		compile_settings = function()
 			if os.istarget("windows") then

build/premake/premake5.lua

@@ -706,7 +706,6 @@ function setup_all_libs ()
 	}
 	extern_libs = {
 		"boost",
-		"opengl",
 		"spidermonkey",
 		"fmt",
 	}
@@ -747,7 +746,6 @@ function setup_all_libs ()
 		"spidermonkey",
 		"sdl",	-- key definitions
 		"libxml2",
-		"opengl",
 		"zlib",
 		"boost",
 		"enet",
@@ -779,7 +777,6 @@ function setup_all_libs ()
 		"third_party/ogre3d_preprocessor"
 	}
 	extern_libs = {
-		"opengl",
 		"sdl",	-- key definitions
 		"spidermonkey",	-- for graphics/scripting
 		"boost",
@@ -800,7 +797,6 @@ function setup_all_libs ()
 	extern_libs = {
 		"boost",
 		"sdl",	-- key definitions
-		"opengl",
 		"spidermonkey",
 		"fmt",
 	}
@@ -818,7 +814,6 @@ function setup_all_libs ()
 	extern_libs = {
 		"spidermonkey",
 		"sdl",	-- key definitions
-		"opengl",
 		"boost",
 		"enet",
 		"tinygettext",
@@ -853,7 +848,6 @@ function setup_all_libs ()
 		"boost",
 		"sdl",
 		"openal",
-		"opengl",
 		"libpng",
 		"zlib",
 		"valgrind",
@@ -917,7 +911,7 @@ function setup_all_libs ()
 	setup_static_lib_project("lowlevel", source_dirs, extern_libs, extra_params)
 
 
-	setup_static_lib_project("gladwrapper", {}, { "opengl", "glad" }, { no_pch = 1 })
+	setup_static_lib_project("gladwrapper", {}, { "glad" }, { no_pch = 1 })
 	glad_path = libraries_source_dir.."glad/"
 	sysincludedirs { glad_path.."include" }
 	if _OPTIONS["gles"] then
@@ -964,7 +958,6 @@ end
 
 -- used for main EXE as well as test
 used_extern_libs = {
-	"opengl",
 	"sdl",
 
 	"libpng",

source/lib/ogl.cpp

@@ -46,10 +46,6 @@
 #include <string.h>
 #include <stdarg.h>
 
-#if MSC_VERSION
-#pragma comment(lib, "opengl32.lib")
-#endif
-
 
 //----------------------------------------------------------------------------
 // extensions

source/renderer/backend/gl/Device.cpp

@@ -133,6 +133,9 @@ std::unique_ptr<CDevice> CDevice::Create(SDL_Window* window)
 
 	if (window)
 	{
+		// According to https://wiki.libsdl.org/SDL_CreateWindow we don't need to
+		// call SDL_GL_LoadLibrary if we have a window with SDL_WINDOW_OPENGL,
+		// because it'll be called internally for the first created window.
 		device->m_Window = window;
 		device->m_Context = SDL_GL_CreateContext(device->m_Window);
 		if (!device->m_Context)
@@ -150,7 +153,6 @@ std::unique_ptr<CDevice> CDevice::Create(SDL_Window* window)
 	}
 	else
 	{
-		// SDL_GL_GetProcAddress is available because we called SDL_GL_LoadLibrary.
 #if OS_WIN
 		ogl_Init(SDL_GL_GetProcAddress, wutil_GetAppHDC());
 #elif defined(SDL_VIDEO_DRIVER_X11) && !CONFIG2_GLES

source/tools/atlas/GameInterface/Handlers/GraphicsSetupHandlers.cpp

@@ -32,6 +32,7 @@
 #include "lib/timer.h"
 #include "maths/MathUtil.h"
 #include "ps/CConsole.h"
+#include "ps/CLogger.h"
 #include "ps/Filesystem.h"
 #include "ps/Profile.h"
 #include "ps/Profiler2.h"
@@ -97,14 +98,18 @@ MESSAGEHANDLER(InitSDL)
 	// When running in Atlas, we skip the SDL video initialisation code
 	// which loads the library, and so SDL_GL_GetProcAddress fails (in
 	// ogl.cpp importExtensionFunctions).
-	// (TODO: I think this is meant to be context-independent, i.e. it
-	// doesn't matter that we're getting extensions from SDL-initialised
-	// GL stuff instead of from the wxWidgets-initialised GL stuff, but that
-	// should be checked.)
 	// So, make sure it's loaded:
 	SDL_InitSubSystem(SDL_INIT_VIDEO);
-	SDL_GL_LoadLibrary(NULL); // NULL = use default
-	// (it shouldn't hurt if this is called multiple times, I think)
+	// wxWidgets doesn't use a proper approach to dynamically load functions and
+	// doesn't provide GetProcAddr-like function. Technically we need to call
+	// SDL_GL_LoadLibrary inside GL device creation, but that might lead to a
+	// crash on Windows because of a wrong order of initialization between SDL
+	// and wxWidgets context management. So leave the call as is while it works.
+	// Refs:
+	//   http://trac.wxwidgets.org/ticket/9213
+	//   http://trac.wxwidgets.org/ticket/9215
+	if (SDL_GL_LoadLibrary(nullptr) && g_Logger)
+		LOGERROR("SDL failed to load GL library: '%s'", SDL_GetError());
 }
 
 MESSAGEHANDLER(InitGraphics)