From d8f2a01f42a8e0f8141a4d2a5e93aaa8262bd539 Mon Sep 17 00:00:00 2001
From: vanfanel <redwindwanderer@gmail.com>
Date: Wed, 7 Apr 2021 01:32:19 +0200
Subject: [PATCH] Add GLVND OpenGL detection as a GLX(X11) alternative and
 remove the glut header.

---
 CMakeLists.txt | 12 +++++++++++-
 src/main.hpp   |  1 -
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b5a9a38bc..3b12acf42 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -234,7 +234,17 @@ IF (APPLE)
   find_package(SDL2_ttf REQUIRED)
   find_package(IOKit REQUIRED)
 ELSE (APPLE)
-	find_package(OpenGL REQUIRED)
+
+        find_package(OpenGL QUIET)
+	IF(OpenGL_FOUND)
+		message(STATUS "Using OpenGL GLX for OpenGL")
+	ELSE(OpenGL_FOUND)
+		# If we couldn't find old GLX package, try to use modern libglvnd libOpenGL.so instead.
+		message(STATUS "Using GLVND for OpenGL")
+		FIND_LIBRARY(OpenGL_LIBRARY OpenGL)
+		SET(EXTRA_LIBS ${OpenGL_LIBRARY})
+        ENDIF(OpenGL_FOUND)
+
 	IF(NOT WIN32)
 		INCLUDE(FindPkgConfig)
 		PKG_SEARCH_MODULE(SDL2 REQUIRED sdl2)
diff --git a/src/main.hpp b/src/main.hpp
index 5f62c08ff..59f70673e 100644
--- a/src/main.hpp
+++ b/src/main.hpp
@@ -116,7 +116,6 @@ extern bool autoLimbReload;
  #ifndef NINTENDO
   #define GL_GLEXT_PROTOTYPES
   #include <GL/gl.h>
-  #include <GL/glu.h>
  #endif
  #include <GL/glext.h>
  #include "SDL_opengl.h"