Merge pull request #1004 from Edreva/generic-slm-fixes

GenericSLM: Sync refresh waiter to connected SLM, not primary monitor

Author: marktsuchida

DeviceAdapters/GenericSLM/GenericSLM.cpp

@@ -226,6 +226,10 @@ int GenericSLM::Initialize()
       (monitorName_.empty() ? "Test Mode" : monitorName_) +
       "]";
 
+   if (refreshWaiter_.SetMonitor(monitorName_) != 0)
+       LogMessage("Could not attach vertical sync to " + monitorName_ +
+           ", reverting to primary display");
+
    windowThread_ = new SLMWindowThread(monitorName_.empty(),
          windowTitle, x, y, w, h);
    windowThread_->Show();

DeviceAdapters/GenericSLM/RefreshWaiter.cpp

@@ -17,47 +17,118 @@
 #include "RefreshWaiter.h"
 
 
-RefreshWaiter::RefreshWaiter()
+namespace {
+
+    struct FindGuidContext
+    {
+        const std::string* monitorName;
+        GUID guid;
+        bool found;
+    };
+
+    // https://learn.microsoft.com/en-us/windows/win32/api/ddraw/nc-ddraw-lpddenumcallbackexa
+    BOOL WINAPI FindGuidForMonitor(GUID* pGUID, LPSTR,
+        LPSTR, LPVOID pContext, HMONITOR mointorHandle)
+    {   
+        FindGuidContext* ctx = static_cast<FindGuidContext*>(pContext);
+        if (pGUID == 0 || mointorHandle == 0)
+            return TRUE; 
+
+        MONITORINFOEXA info;
+        info.cbSize = sizeof(info);
+        if (GetMonitorInfoA(mointorHandle, &info) && *ctx->monitorName == info.szDevice)
+        {
+            ctx->guid = *pGUID;
+            ctx->found = true;
+            return FALSE;
+        }
+        return TRUE;
+    }
+
+}
+
+
+RefreshWaiter::RefreshWaiter() :
+    hDDrawLib_(0),
+    directDrawCreate_(0),
+    directDrawEnumerateEx_(0),
+    directDraw_(0)
 {
-   hDDrawLib_ = LoadLibraryA("ddraw.dll");
-   if (!hDDrawLib_)
-      return;
-
-   directDrawCreate_ = (DirectDrawCreateFunc)GetProcAddress(hDDrawLib_,
-            "DirectDrawCreate");
-   if (!directDrawCreate_)
-      return;
-
-   HRESULT hr = directDrawCreate_(0, &directDraw_, 0);
-   if (hr != DD_OK)
-   {
-      directDraw_ = 0;
-      return;
-   }
+    hDDrawLib_ = LoadLibraryA("ddraw.dll");
+    if (!hDDrawLib_)
+        return;
+
+    directDrawCreate_ = (DirectDrawCreateFunc)GetProcAddress(hDDrawLib_,
+        "DirectDrawCreate");
+    directDrawEnumerateEx_ = (DirectDrawEnumerateExFunc)GetProcAddress(hDDrawLib_,
+        "DirectDrawEnumerateExA");
+    if (!directDrawCreate_)
+        return;
+
+    HRESULT hr = directDrawCreate_(0, &directDraw_, 0);
+    if (hr != DD_OK)
+    {
+        directDraw_ = 0;
+        return;
+    }
 }
 
 
 RefreshWaiter::~RefreshWaiter()
 {
-   if (directDraw_)
-      directDraw_->Release();
+    if (directDraw_)
+        directDraw_->Release();
+
+    if (hDDrawLib_)
+        FreeLibrary(hDDrawLib_);
+}
+
+
+int RefreshWaiter::SetMonitor(const std::string& monitorName)
+{
+    if (!directDrawCreate_)
+        return 1;
+
+    GUID* pGuid = 0;
+    FindGuidContext ctx;
+    ctx.monitorName = &monitorName;
+    ctx.found = false;
+
+    if (!monitorName.empty())
+    {
+        if (!directDrawEnumerateEx_)
+            return 1;
+
+        directDrawEnumerateEx_(FindGuidForMonitor, &ctx, DDENUM_ATTACHEDSECONDARYDEVICES);
+        if (!ctx.found)
+            return 1;
+
+        pGuid = &ctx.guid;
+    }
+
+    IDirectDraw* newDirectDraw = 0;
+    HRESULT hr = directDrawCreate_(pGuid, &newDirectDraw, 0);
+    if (hr != DD_OK)
+        return (int)hr;
 
-   if (hDDrawLib_)
-      FreeLibrary(hDDrawLib_);
+    if (directDraw_)
+        directDraw_->Release();
+    directDraw_ = newDirectDraw;
+    return 0;
 }
 
 
 int RefreshWaiter::WaitForVerticalBlank()
 {
-   if (!directDraw_)
-      return 1;
+    if (!directDraw_)
+        return 1;
 
-   HRESULT result =  directDraw_->WaitForVerticalBlank(DDWAITVB_BLOCKBEGIN, 0); 
+    HRESULT result =  directDraw_->WaitForVerticalBlank(DDWAITVB_BLOCKBEGIN, 0);
 
-   if (result == DD_OK)
-   {
-      return 0;
-   }
-   return (int) result;
+    if (result == DD_OK)
+    {
+        return 0;
+    }
+    return (int) result;
 
 }

DeviceAdapters/GenericSLM/RefreshWaiter.h

@@ -19,17 +19,22 @@
 #include <Windows.h>
 #include <ddraw.h>
 
+#include <string>
+
 
 class RefreshWaiter
 {
    HMODULE hDDrawLib_;
    typedef HRESULT (WINAPI *DirectDrawCreateFunc)(GUID*, LPDIRECTDRAW*, IUnknown*);
+   typedef HRESULT (WINAPI *DirectDrawEnumerateExFunc)(LPDDENUMCALLBACKEXA, LPVOID, DWORD);
    DirectDrawCreateFunc directDrawCreate_;
+   DirectDrawEnumerateExFunc directDrawEnumerateEx_;
    IDirectDraw* directDraw_;
 
 public:
    RefreshWaiter();
    ~RefreshWaiter();
 
+   int SetMonitor(const std::string& monitorName);
    int WaitForVerticalBlank();
-};
+};