Henri Verbeet : wined3d: Restore the thread's GL context on context_release () if it wasn't created by wined3d.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: c0050b8ec91b60d6d6a646095cc22f9856eafeda
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=c0050b8ec91b60d6d6a646095c...

Author: Henri Verbeet <hverbeet(a)codeweavers.com>
Date:   Wed Oct 28 11:00:13 2009 +0100

wined3d: Restore the thread's GL context on context_release() if it wasn't created by wined3d.

The background on this is that some applications use OpenGL and DirectDraw/Direct3D on
the same thread, typically using OpenGL for rendering and DirectDraw to get
the amount of available video memory. This means that we might replace the
application's current GL context with one with a completely different state,
but also that our current GL context might not be what we think it is.

---

 dlls/wined3d/context.c         |   50 +++++++++++++++++++++++++++++++++++----
 dlls/wined3d/wined3d_private.h |    2 +
 2 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/dlls/wined3d/context.c b/dlls/wined3d/context.c
index 1362352..deafe72 100644
--- a/dlls/wined3d/context.c
+++ b/dlls/wined3d/context.c
@@ -843,7 +843,37 @@ void context_release(struct wined3d_context *context)
             WARN("Context %p is not the current context.\n", context);
     }
 
-    --context->level;
+    if (!--context->level && context->restore_ctx)
+    {
+        TRACE("Restoring GL context %p on device context %p.\n", context->restore_ctx, context->restore_dc);
+        if (!pwglMakeCurrent(context->restore_dc, context->restore_ctx))
+        {
+            DWORD err = GetLastError();
+            ERR("Failed to restore GL context %p on device context %p, last error %#x.\n",
+                    context->restore_ctx, context->restore_dc, err);
+        }
+        context->restore_ctx = NULL;
+        context->restore_dc = NULL;
+    }
+}
+
+static void context_enter(struct wined3d_context *context)
+{
+    TRACE("Entering context %p, level %u.\n", context, context->level + 1);
+
+    if (!context->level++)
+    {
+        const struct wined3d_context *current_context = context_get_current();
+        HGLRC current_gl = pwglGetCurrentContext();
+
+        if (current_gl && (!current_context || current_context->glCtx != current_gl))
+        {
+            TRACE("Another GL context (%p on device context %p) is already current.\n",
+                    current_gl, pwglGetCurrentDC());
+            context->restore_ctx = current_gl;
+            context->restore_dc = pwglGetCurrentDC();
+        }
+    }
 }
 
 /*****************************************************************************
@@ -1347,10 +1377,13 @@ struct wined3d_context *context_create(IWineD3DDeviceImpl *This, IWineD3DSurface
     list_init(&ret->fbo_list);
     list_init(&ret->fbo_destroy_list);
 
+    context_enter(ret);
+
     /* Set up the context defaults */
     if (!context_set_current(ret))
     {
         ERR("Cannot activate context to set up defaults\n");
+        context_release(ret);
         goto out;
     }
 
@@ -1447,8 +1480,6 @@ struct wined3d_context *context_create(IWineD3DDeviceImpl *This, IWineD3DSurface
 
     This->frag_pipe->enable_extension((IWineD3DDevice *) This, TRUE);
 
-    ++ret->level;
-
     return ret;
 
 out:
@@ -2078,9 +2109,7 @@ struct wined3d_context *context_acquire(IWineD3DDeviceImpl *This, IWineD3DSurfac
     TRACE("(%p): Selecting context for render target %p, thread %d\n", This, target, tid);
 
     context = FindContext(This, target, tid);
-    ++context->level;
-    TRACE("Found context %p, level %u.\n", context, context->level);
-
+    context_enter(context);
     if (!context->valid) return context;
 
     gl_info = context->gl_info;
@@ -2104,6 +2133,15 @@ struct wined3d_context *context_acquire(IWineD3DDeviceImpl *This, IWineD3DSurfac
             This->highest_dirty_ps_const = This->d3d_pshader_constantF;
         }
     }
+    else if (context->restore_ctx)
+    {
+        if (!pwglMakeCurrent(context->hdc, context->glCtx))
+        {
+            DWORD err = GetLastError();
+            ERR("Failed to make GL context %p current on device context %p, last error %#x.\n",
+                    context->hdc, context->glCtx, err);
+        }
+    }
 
     switch (usage) {
         case CTXUSAGE_CLEAR:
diff --git a/dlls/wined3d/wined3d_private.h b/dlls/wined3d/wined3d_private.h
index 0617bbc..d8f65b0 100644
--- a/dlls/wined3d/wined3d_private.h
+++ b/dlls/wined3d/wined3d_private.h
@@ -1060,6 +1060,8 @@ struct wined3d_context
 
     /* The actual opengl context */
     UINT level;
+    HGLRC restore_ctx;
+    HDC restore_dc;
     HGLRC                   glCtx;
     HWND                    win_handle;
     HDC                     hdc;