From 0399bfd058316a84177662276c0b0a424ff6e557 Mon Sep 17 00:00:00 2001
From: Haroon Qureshi <haroonq@google.com>
Date: Fri, 1 May 2026 00:17:41 -0700
Subject: [PATCH] Allow custom getProcAddress for glad resolution.

PiperOrigin-RevId: 908587023
Change-Id: Idc4dcc5ee8d2d67f83486ca2ff4667f2b4b283eb
---
 src/render/classic/glad/glad.c    | 15 +++++++++------
 src/render/classic/glad/glad.h    |  2 +-
 src/render/classic/glad/loader.cc |  2 +-
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/src/render/classic/glad/glad.c b/src/render/classic/glad/glad.c
index e570906d..41fe00ae 100644
--- a/src/render/classic/glad/glad.c
+++ b/src/render/classic/glad/glad.c
@@ -86,7 +86,7 @@ static PFNWGLGETPROCADDRESSPROC_PRIVATE mjGladGetProcAddressPtr;
 #endif
 
 static
-int mjGlad_open_gl(void) {
+int mjGlad_open_gl(void* get_proc_address) {
 #ifndef IS_UWP
   mjGlad_libGL = LoadLibraryW(L"opengl32.dll");
   if(mjGlad_libGL != NULL) {
@@ -164,8 +164,11 @@ static int mjGlad_dl_iterate_callback(struct dl_phdr_info* info, size_t size, vo
   return result;
 }
 
-static int mjGlad_open_gl(void) {
-  mjGladGetProcAddressPtr = NULL;
+static int mjGlad_open_gl(void* get_proc_address) {
+  mjGladGetProcAddressPtr = (PFNGLXGETPROCADDRESSPROC_PRIVATE)get_proc_address;
+  if (mjGladGetProcAddressPtr != NULL) {
+    return 1;
+  }
 
   // We try to load a GetProcAddress symbol that's already been loaded into the process first.
   // Since MuJoCo relies on user code to set up a working OpenGL environment, one of these symbols
@@ -224,7 +227,7 @@ static int mjGlad_open_gl(void) {
   return mjGladGetProcAddressPtr ? 1 : 0;
 }
 #else
-static int mjGlad_open_gl(void) {
+static int mjGlad_open_gl(void* get_proc_address) {
   static const char *NAMES[] = {
       "../Frameworks/OpenGL.framework/OpenGL",
       "/Library/Frameworks/OpenGL.framework/OpenGL",
@@ -1490,8 +1493,8 @@ static void mjGlad_find_coreGL(void) {
   }
 }
 
-int mjGladLoadGLUnsafe(void) {
-  if (mjGlad_open_gl()) {
+int mjGladLoadGLUnsafe(void* get_proc_address) {
+  if (mjGlad_open_gl(get_proc_address)) {
     mjGLVersion.major = 0; mjGLVersion.minor = 0;
     glGetString = (PFNGLGETSTRINGPROC)mjGlad_get_proc("glGetString");
     if (glGetString == NULL) return 0;
diff --git a/src/render/classic/glad/glad.h b/src/render/classic/glad/glad.h
index 419968bc..44c700cb 100644
--- a/src/render/classic/glad/glad.h
+++ b/src/render/classic/glad/glad.h
@@ -114,7 +114,7 @@ GLAPI struct gladGLversionStruct mjGLVersion;
 
 GLAPI int mjGladLoadGL(void);
 
-GLAPI int mjGladLoadGLUnsafe(void) MJGLAD_NOEXCEPT;
+GLAPI int mjGladLoadGLUnsafe(void*) MJGLAD_NOEXCEPT;
 
 typedef unsigned int GLenum;
 typedef unsigned char GLboolean;
diff --git a/src/render/classic/glad/loader.cc b/src/render/classic/glad/loader.cc
index 5eb1638e..b43357c3 100644
--- a/src/render/classic/glad/loader.cc
+++ b/src/render/classic/glad/loader.cc
@@ -17,7 +17,7 @@
 extern "C" {
 
 GLAPI int mjGladLoadGL() {
-  static const int glad_initialized = mjGladLoadGLUnsafe();
+  static const int glad_initialized = mjGladLoadGLUnsafe(nullptr);
   return glad_initialized;
 }