From 05b02d6b3e2c3621e620a467effa22818541cbdc Mon Sep 17 00:00:00 2001
From: Erwin Coumans <erwin.coumans@gmail.com>
Date: Thu, 22 Feb 2018 09:08:10 -0800
Subject: [PATCH] fix glx include

---
 build3/findOpenGLGlewGlut.lua             | 17 +++++++++++++----
 build3/premake4.lua                       |  6 ++++++
 examples/OpenGLWindow/X11OpenGLWindow.cpp |  2 +-
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/build3/findOpenGLGlewGlut.lua b/build3/findOpenGLGlewGlut.lua
index 230424021..4e44e0556 100644
--- a/build3/findOpenGLGlewGlut.lua
+++ b/build3/findOpenGLGlewGlut.lua
@@ -63,13 +63,22 @@
 
 		if os.is("Linux") then
 			configuration{"Linux"}
-				print("Using glad and dynamic loading of glx functions")
-			 	defines { "GLEW_STATIC","GLEW_DYNAMIC_LOAD_ALL_GLX_FUNCTIONS=1"}
+				if  _OPTIONS["enable_system_glx"] then --# and (os.isdir("/usr/include") and os.isfile("/usr/include/GL/glx.h")) then
+                                	links{"X11","pthread"}
+					print("Using system GL/glx.h")
+                        	else
+					print("Using glad_glx")
+				 	defines { "GLEW_DYNAMIC_LOAD_ALL_GLX_FUNCTIONS=1"}	
+				 	files { 
+					projectRootDir .. "examples/ThirdPartyLibs/glad/glad_glx.c"}
+				end
+
+				print("Using glad and dynamic loading of GL functions")
+			 	defines { "GLEW_STATIC"}
                         	includedirs {
                                         projectRootDir .. "examples/ThirdPartyLibs/glad"
                         	}
-                        	files { projectRootDir .. "examples/ThirdPartyLibs/glad/glad.c",
-					projectRootDir .. "examples/ThirdPartyLibs/glad/glad_glx.c"}
+                        	files { projectRootDir .. "examples/ThirdPartyLibs/glad/glad.c"}
 				links {"dl"}
 
 		end
diff --git a/build3/premake4.lua b/build3/premake4.lua
index e0aa42acd..a39e926e5 100644
--- a/build3/premake4.lua
+++ b/build3/premake4.lua
@@ -28,6 +28,12 @@
 		description = "Enable iOS target (requires xcode4)"
 	}
 
+	newoption
+	{
+		trigger = "enable_system_glx",
+		description = "Try to link against system glx instead of using glad_glx (default)"
+	}
+
 	newoption
 	{
 		trigger = "enable_system_opengl",
diff --git a/examples/OpenGLWindow/X11OpenGLWindow.cpp b/examples/OpenGLWindow/X11OpenGLWindow.cpp
index 72d7b4589..3fcb51454 100644
--- a/examples/OpenGLWindow/X11OpenGLWindow.cpp
+++ b/examples/OpenGLWindow/X11OpenGLWindow.cpp
@@ -15,7 +15,7 @@
 #ifdef GLEW_DYNAMIC_LOAD_ALL_GLX_FUNCTIONS
 #include "glad/glad_glx.h"
 #else
-#include "GL/glx.h"
+#include <GL/glx.h>
 #endif // GLEW_DYNAMIC_LOAD_ALL_GLX_FUNCTIONS
 #include <assert.h>