ddraw: Implement ForceRefreshRate registry entry for overriding DirectX refresh rate.

dlls/ddraw/ddraw.c

@@ -3,6 +3,7 @@
  * Copyright 1998-2000 Lionel Ulmer
  * Copyright 2000-2001 TransGaming Technologies Inc.
  * Copyright 2006 Stefan Dsinger
+ * Copyright 2008 Denver Gingerich
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -534,29 +535,19 @@ IDirectDrawImpl_SetCooperativeLevel(IDirectDraw7 *iface,
 }
 
 /*****************************************************************************
- * IDirectDraw7::SetDisplayMode
- *
- * Sets the display screen resolution, color depth and refresh frequency
- * when in fullscreen mode (in theory).
- * Possible return values listed in the SDK suggest that this method fails
- * when not in fullscreen mode, but this is wrong. Windows 2000 happily sets
- * the display mode in DDSCL_NORMAL mode without an hwnd specified.
- * It seems to be valid to pass 0 for With and Height, this has to be tested
- * It could mean that the current video mode should be left as-is. (But why
- * call it then?)
  *
- * Params:
- *  Height, Width: Screen dimension
- *  BPP: Color depth in Bits per pixel
- *  Refreshrate: Screen refresh rate
- *  Flags: Other stuff
+ * Helper function for SetDisplayMode and RestoreDisplayMode
  *
- * Returns
- *  DD_OK on success
+ * Implements DirectDraw's SetDisplayMode, but ignores the value of
+ * ForceRefreshRate, since it is already handled by
+ * IDirectDrawImpl_SetDisplayMode.  RestoreDisplayMode can use this function
+ * without worrying that ForceRefreshRate will override the refresh rate.  For
+ * argument and return value documentation, see
+ * IDirectDrawImpl_SetDisplayMode.
  *
  *****************************************************************************/
-static HRESULT WINAPI
-IDirectDrawImpl_SetDisplayMode(IDirectDraw7 *iface,
+static HRESULT
+IDirectDrawImpl_SetDisplayModeNoOverride(IDirectDraw7 *iface,
                                          DWORD Width,
                                          DWORD Height,
                                          DWORD BPP,
@@ -616,6 +607,46 @@ IDirectDrawImpl_SetDisplayMode(IDirectDraw7 *iface,
 }
 
 /*****************************************************************************
+ * IDirectDraw7::SetDisplayMode
+ *
+ * Sets the display screen resolution, color depth and refresh frequency
+ * when in fullscreen mode (in theory).
+ * Possible return values listed in the SDK suggest that this method fails
+ * when not in fullscreen mode, but this is wrong. Windows 2000 happily sets
+ * the display mode in DDSCL_NORMAL mode without an hwnd specified.
+ * It seems to be valid to pass 0 for With and Height, this has to be tested
+ * It could mean that the current video mode should be left as-is. (But why
+ * call it then?)
+ *
+ * Params:
+ *  Height, Width: Screen dimension
+ *  BPP: Color depth in Bits per pixel
+ *  Refreshrate: Screen refresh rate
+ *  Flags: Other stuff
+ *
+ * Returns
+ *  DD_OK on success
+ *
+ *****************************************************************************/
+static HRESULT WINAPI
+IDirectDrawImpl_SetDisplayMode(IDirectDraw7 *iface,
+                               DWORD Width,
+                               DWORD Height,
+                               DWORD BPP,
+                               DWORD RefreshRate,
+                               DWORD Flags)
+{
+    if (force_refresh_rate != 0)
+    {
+        TRACE("ForceRefreshRate overriding passed-in refresh rate (%d Hz) to %d Hz\n", RefreshRate, force_refresh_rate);
+        RefreshRate = force_refresh_rate;
+    }
+
+    return IDirectDrawImpl_SetDisplayModeNoOverride(iface, Width, Height, BPP,
+                                                    RefreshRate, Flags);
+}
+
+/*****************************************************************************
  * IDirectDraw7::RestoreDisplayMode
  *
  * Restores the display mode to what it was at creation time. Basically.
@@ -642,7 +673,7 @@ IDirectDrawImpl_RestoreDisplayMode(IDirectDraw7 *iface)
     ICOM_THIS_FROM(IDirectDrawImpl, IDirectDraw7, iface);
     TRACE("(%p)\n", This);
 
-    return IDirectDraw7_SetDisplayMode(ICOM_INTERFACE(This, IDirectDraw7),
+    return IDirectDrawImpl_SetDisplayModeNoOverride(ICOM_INTERFACE(This, IDirectDraw7),
                                                     This->orig_width,
                                                     This->orig_height,
                                                     This->orig_bpp,

dlls/ddraw/ddraw_private.h

@@ -83,6 +83,8 @@ extern ULONG WINAPI D3D7CB_DestroyDepthStencilSurface(IWineD3DSurface *pSurface)
 /* Global critical section */
 extern CRITICAL_SECTION ddraw_cs;
 
+extern DWORD force_refresh_rate;
+
 /*****************************************************************************
  * IDirectDraw implementation structure
  *****************************************************************************/

dlls/ddraw/main.c

@@ -4,6 +4,7 @@
  * Copyright 1998 Lionel Ulmer
  * Copyright 2000-2001 TransGaming Technologies Inc.
  * Copyright 2006 Stefan Dsinger
+ * Copyright 2008 Denver Gingerich
  *
  * This file contains the (internal) driver registration functions,
  * driver enumeration APIs and DirectDraw creation functions.
@@ -68,6 +69,9 @@ static CRITICAL_SECTION_DEBUG ddraw_cs_debug =
 };
 CRITICAL_SECTION ddraw_cs = { &ddraw_cs_debug, -1, 0, 0, 0, 0 };
 
+/* value of ForceRefreshRate */
+DWORD force_refresh_rate = 0;
+
 /***********************************************************************
  *
  * Helper function for DirectDrawCreate and friends
@@ -886,6 +890,38 @@ DllMain(HINSTANCE hInstDLL,
             }
         }
 
+        /* On Windows one can force the refresh rate that DirectDraw uses by
+         * setting an override value in dxdiag.  This is documented in KB315614
+         * (main article), KB230002, and KB217348.  By comparing registry dumps
+         * before and after setting the override, we see that the override value
+         * is stored in HKLM\Software\Microsoft\DirectDraw\ForceRefreshRate as a
+         * DWORD that represents the refresh rate to force.  We use this
+         * registry entry to modify the behavior of SetDisplayMode so that Wine
+         * users can override the refresh rate in a Windows-compatible way.
+         *
+         * dxdiag will not accept a refresh rate lower than 40 or higher than
+         * 120 so this value should be within that range.  It is, of course,
+         * possible for a user to set the registry entry value directly so that
+         * assumption might not hold.
+         *
+         * There is no current mechanism for setting this value through the Wine
+         * GUI.  It would be most appropriate to set this value through a dxdiag
+         * clone, but it may be sufficient to use winecfg.
+         *
+         * TODO: Create a mechanism for setting this value through the Wine GUI.
+         */
+        if ( !RegOpenKeyA( HKEY_LOCAL_MACHINE, "Software\\Microsoft\\DirectDraw", &hkey ) )
+        {
+            DWORD type, data;
+            size = sizeof(data);
+            if (!RegQueryValueExA( hkey, "ForceRefreshRate", NULL, &type, (LPBYTE)&data, &size ) && type == REG_DWORD)
+            {
+                TRACE("ForceRefreshRate set; overriding refresh rate to %d Hz\n", data);
+                force_refresh_rate = data;
+            }
+            RegCloseKey( hkey );
+        }
+
         DisableThreadLibraryCalls(hInstDLL);
     }
     else if (Reason == DLL_PROCESS_DETACH)