[Feat] (WGL): add Windows host layer - drop-in opengl32.dll with WGL over EGLImpl, Win32 window backend plumbing for both backends, ANGLE loader path, and leak-at-exit process teardown

MobileGL/MG_Backend/BackendObject.h

@@ -313,7 +313,8 @@ namespace MobileGL {
             Android,
             X11,
             MetalLayer,
-            // TODO: Wayland, Windows, etc.
+            Win32, // Handle is an HWND
+            // TODO: Wayland, etc.
             WindowBackendCount,
             Unknown = -1
         };

MobileGL/MG_Backend/DirectGLES/BackendObject_DirectGLES.cpp

@@ -701,9 +701,10 @@ namespace MobileGL::MG_Backend::DirectGLES {
 
         if ((handle.Backend != WindowBackend::Android &&
              handle.Backend != WindowBackend::X11 &&
-             handle.Backend != WindowBackend::MetalLayer) ||
+             handle.Backend != WindowBackend::MetalLayer &&
+             handle.Backend != WindowBackend::Win32) ||
             !handle.Handle) {
-            MGLOG_E("DirectGLES backend only supports Android, X11, and CAMetalLayer native windows");
+            MGLOG_E("DirectGLES backend only supports Android, X11, CAMetalLayer, and Win32 native windows");
             return false;
         }
 

MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp

@@ -4307,9 +4307,23 @@ namespace MobileGL::MG_Backend::DirectGLES {
 
         if (!ChooseConfigForSurface(surfaceBit, g_Config, window)) return false;
 
-        const EGLint contextAttribs[] = {EGL_CONTEXT_CLIENT_VERSION, 3, EGL_NONE};
+        // Negotiate the highest ES 3.x context. Version-strict EGL implementations
+        // (ANGLE) return exactly the requested minor, and a bare CLIENT_VERSION 3
+        // request yields a 3.0 context that lacks the 3.1/3.2 texture targets the
+        // capability probes exercise; mobile drivers ignore the minor and hand out
+        // their maximum either way.
+        for (const EGLint minorVersion : {2, 1, 0}) {
+            const EGLint contextAttribs[] = {EGL_CONTEXT_MAJOR_VERSION, 3,
+                                             EGL_CONTEXT_MINOR_VERSION, minorVersion,
+                                             EGL_NONE};
+            g_Context = g_EGLFuncs.eglCreateContext(g_Display, g_Config, EGL_NO_CONTEXT, contextAttribs);
+            if (g_Context != EGL_NO_CONTEXT) {
+                return true;
+            }
+        }
 
-        g_Context = g_EGLFuncs.eglCreateContext(g_Display, g_Config, EGL_NO_CONTEXT, contextAttribs);
+        const EGLint legacyContextAttribs[] = {EGL_CONTEXT_CLIENT_VERSION, 3, EGL_NONE};
+        g_Context = g_EGLFuncs.eglCreateContext(g_Display, g_Config, EGL_NO_CONTEXT, legacyContextAttribs);
         return g_Context != EGL_NO_CONTEXT;
     }
 

MobileGL/MG_Backend/DirectVulkan/BackendObject_DirectVulkan.cpp

@@ -397,8 +397,9 @@ namespace MobileGL::MG_Backend::DirectVulkan {
         }
         if (!handle.Handle || (handle.Backend != WindowBackend::Android &&
                                handle.Backend != WindowBackend::X11 &&
-                               handle.Backend != WindowBackend::MetalLayer)) {
-            MGLOG_E("DirectVulkan backend only supports Android, X11, and CAMetalLayer native windows");
+                               handle.Backend != WindowBackend::MetalLayer &&
+                               handle.Backend != WindowBackend::Win32)) {
+            MGLOG_E("DirectVulkan backend only supports Android, X11, CAMetalLayer, and Win32 native windows");
             return false;
         }
 

MobileGL/MG_Backend/DirectVulkan/Renderer/VulkanRenderer.cpp

@@ -7560,6 +7560,10 @@ void main() {
         MOBILEGL_ASSERT(hwnd, "HWND is null");
 
         VkWin32SurfaceCreateInfoKHR sci{VK_STRUCTURE_TYPE_WIN32_SURFACE_CREATE_INFO_KHR};
+        sci.hinstance = reinterpret_cast<HINSTANCE>(GetWindowLongPtrW(hwnd, GWLP_HINSTANCE));
+        if (!sci.hinstance) {
+            sci.hinstance = GetModuleHandleW(nullptr);
+        }
         sci.hwnd = hwnd;
         VK_VERIFY(vkCreateWin32SurfaceKHR(m_instance, &sci, nullptr, &m_surface), "vkCreateWin32SurfaceKHR failed");
 #elif defined VK_USE_PLATFORM_METAL_EXT