From 0793032ece45b35080eddf3f97496a67b94d449a Mon Sep 17 00:00:00 2001
From: offtkp <parisoplop@gmail.com>
Date: Sat, 10 Aug 2024 20:05:25 +0300
Subject: [PATCH] Update windows createpbuffer implementation to latest from
 duckstation

---
 third_party/duckstation/gl/context_wgl.cpp | 31 ++++++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/third_party/duckstation/gl/context_wgl.cpp b/third_party/duckstation/gl/context_wgl.cpp
index 47ec4b1e..b2e0d2e5 100644
--- a/third_party/duckstation/gl/context_wgl.cpp
+++ b/third_party/duckstation/gl/context_wgl.cpp
@@ -149,8 +149,8 @@ std::unique_ptr<Context> ContextWGL::CreateSharedContext(const WindowInfo& wi)
   }
   else
   {
-    Log_ErrorPrint("PBuffer not implemented");
-    return nullptr;
+    if (!context->CreatePBuffer())
+      return nullptr;
   }
 
   if (m_version.profile == Profile::NoProfile)
@@ -305,6 +305,32 @@ bool ContextWGL::CreatePBuffer()
 
   static constexpr const int pb_attribs[] = {0, 0};
 
+  HGLRC temp_rc = nullptr;
+  ScopedGuard temp_rc_guard([&temp_rc, hdc]() {
+    if (temp_rc)
+    {
+      wglMakeCurrent(hdc, nullptr);
+      wglDeleteContext(temp_rc);
+    }
+  });
+
+  if (!GLAD_WGL_ARB_pbuffer)
+  {
+    // we're probably running completely surfaceless... need a temporary context.
+    temp_rc = wglCreateContext(hdc);
+    if (!temp_rc || !wglMakeCurrent(hdc, temp_rc))
+    {
+      Log_ErrorPrint("Failed to create temporary context to load WGL for pbuffer.");
+      return false;
+    }
+
+    if (!ReloadWGL(hdc) || !GLAD_WGL_ARB_pbuffer)
+    {
+      Log_ErrorPrint("Missing WGL_ARB_pbuffer");
+      return false;
+    }
+  }
+
   AssertMsg(m_pixel_format.has_value(), "Has pixel format for pbuffer");
   HPBUFFERARB pbuffer = wglCreatePbufferARB(hdc, m_pixel_format.value(), 1, 1, pb_attribs);
   if (!pbuffer)
@@ -326,6 +352,7 @@ bool ContextWGL::CreatePBuffer()
   m_dummy_dc = hdc;
   m_pbuffer = pbuffer;
 
+  temp_rc_guard.Run();
   pbuffer_guard.Cancel();
   hdc_guard.Cancel();
   hwnd_guard.Cancel();