From d51723c153f4e9cba806c8b0f9db504fb61e1cda Mon Sep 17 00:00:00 2001
From: Swung0x48 <swung0x48@outlook.com>
Date: Thu, 11 Jun 2026 10:28:39 +0800
Subject: [PATCH] [Fix] (MG_Backend/DirectGLES): use safer buffer upload path.
 MAY AFFECT PERFORMANCE!!

---
 MobileGL/MG_Backend/DirectGLES/Managers.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/MobileGL/MG_Backend/DirectGLES/Managers.cpp b/MobileGL/MG_Backend/DirectGLES/Managers.cpp
index a8c9dc50..2d5fdd6a 100644
--- a/MobileGL/MG_Backend/DirectGLES/Managers.cpp
+++ b/MobileGL/MG_Backend/DirectGLES/Managers.cpp
@@ -26,7 +26,7 @@
 #include <cctype>
 
 namespace MobileGL::MG_Backend::DirectGLES {
-    constexpr Bool PREFER_MAP_BUFFER_RANGE_FOR_BUFFER_SYNC = true;
+    constexpr Bool PREFER_MAP_BUFFER_RANGE_FOR_BUFFER_SYNC = false;
     constexpr const char* BASE_INSTANCE_UNIFORM_NAME = "mg_BaseInstance";
 
     static Uint ResolveBackendEsslVersion() {
@@ -130,9 +130,11 @@ namespace MobileGL::MG_Backend::DirectGLES {
 
             // glMapBufferRange or glBufferSubData
             Bool useInvalidationMap = !(stateBufferObject->GetChangeBits() & BufferChangeBits::ForbidInvalidationBit);
+            // TODO: MAY AFFECT PERFORMANCE
             Bool useUnsynchronizedMap =
                 !(stateBufferObject->GetChangeBits() & BufferChangeBits::ForbidUnsynchronizationBit);
-            Bool useMapBufferRange = useInvalidationMap || useUnsynchronizedMap;
+            Bool useMapBufferRange = PREFER_MAP_BUFFER_RANGE_FOR_BUFFER_SYNC &&
+                                     (useInvalidationMap || useUnsynchronizedMap);
 
             if (!useMapBufferRange && PREFER_MAP_BUFFER_RANGE_FOR_BUFFER_SYNC) {
                 auto usage = stateBufferObject->GetUsage();