Refactor|LegacyCore: Loop callback function set separately

Now the main loop can be first started without a callback.

doomsday/libdeng2/include/de/c_wrapper.h

@@ -41,7 +41,8 @@ extern "C" {
 DENG2_OPAQUE(LegacyCore)
 
 DENG2_PUBLIC LegacyCore* LegacyCore_New(void* dengApp);
-DENG2_PUBLIC int LegacyCore_RunEventLoop(LegacyCore* lc, void (*loopFunc)(void));
+DENG2_PUBLIC void LegacyCore_SetLoopFunc(LegacyCore* lc, void (*callback)(void));
+DENG2_PUBLIC int LegacyCore_RunEventLoop(LegacyCore* lc);
 DENG2_PUBLIC void LegacyCore_Stop(LegacyCore* lc, int exitCode);
 DENG2_PUBLIC void LegacyCore_Delete(LegacyCore* lc);
 

doomsday/libdeng2/include/de/legacy/legacycore.h

@@ -51,12 +51,17 @@ class LegacyCore : public QObject
      * Starts the deng2 event loop in the current thread. Does not return until
      * the loop is stopped.
      *
-     * @param callback  Function to call periodically from the loop, as
-     *                  often as possible.
-     *
      * @return  Exit code.
      */
-    int runEventLoop(void (*callback)(void));
+    int runEventLoop();
+
+    /**
+     * Sets the callback function that gets called periodically from the main
+     * loop. The calls are made as often as possible without blocking the loop.
+     *
+     * @param callback  Loop callback function.
+     */
+    void setLoopFunc(void (*callback)(void));
 
     /**
      * Stops the event loop. This is automatically called when the core is

doomsday/libdeng2/libdeng2.pro

@@ -65,6 +65,7 @@ macx {
     fixInstallName("QtCore.framework/Versions/4/QtCore")
     fixInstallName("QtNetwork.framework/Versions/4/QtNetwork")
     fixInstallName("QtGui.framework/Versions/4/QtGui")
+    fixInstallName("QtOpenGL.framework/Versions/4/QtOpenGL")
 
     # Update the library included in the main app bundle.
     doPostLink("cp -fRp libdeng2*dylib ../engine/doomsday.app/Contents/Frameworks")

doomsday/libdeng2/src/c_wrapper.cpp

@@ -32,10 +32,16 @@ LegacyCore* LegacyCore_New(void* dengApp)
     return reinterpret_cast<LegacyCore*>(new de::LegacyCore(reinterpret_cast<QApplication*>(dengApp)));
 }
 
-int LegacyCore_RunEventLoop(LegacyCore* lc, void (*loopFunc)(void))
+int LegacyCore_RunEventLoop(LegacyCore* lc)
 {
     DENG2_SELF(LegacyCore, lc);
-    return self->runEventLoop(loopFunc);
+    return self->runEventLoop();
+}
+
+void LegacyCore_SetLoopFunc(LegacyCore* lc, void (*callback)(void))
+{
+    DENG2_SELF(LegacyCore, lc);
+    return self->setLoopFunc(callback);
 }
 
 void LegacyCore_Stop(LegacyCore *lc, int exitCode)

doomsday/libdeng2/src/legacy/legacycore.cpp

@@ -74,13 +74,21 @@ LegacyNetwork& LegacyCore::network()
     return instance().d->network;
 }
 
-int LegacyCore::runEventLoop(void (*func)(void))
+void LegacyCore::setLoopFunc(void (*func)(void))
 {
-    LOG_MSG("Starting LegacyCore event loop...");
-
     // Set up a timer to periodically call the provided callback function.
     d->loopFunc = func;
-    QTimer::singleShot(1, this, SLOT(callback()));
+
+    if(func)
+    {
+        // Start the periodic callback calls.
+        QTimer::singleShot(1, this, SLOT(callback()));
+    }
+}
+
+int LegacyCore::runEventLoop()
+{
+    LOG_MSG("Starting LegacyCore event loop...");
 
     // Run the Qt event loop. In the future this will be replaced by the
     // application's main Qt event loop, where deng2 will hook into.
@@ -100,6 +108,6 @@ void LegacyCore::callback()
     if(d->loopFunc)
     {
         d->loopFunc();
+        QTimer::singleShot(1, this, SLOT(callback()));
     }
-    QTimer::singleShot(1, this, SLOT(callback()));
 }