Disable experimental Syphon output behind a build flag

Author: aalex

src/core/SyphonServerImpl.mm

@@ -48,7 +48,8 @@
 class SyphonServerImpl
 {
 public:
-  SyphonServerImpl() : _server(nil), _serverCtx(NULL) {}
+  SyphonServerImpl()
+    : _server(nil), _serverCtx(NULL), _failed(false), _logged(false) {}
 
   ~SyphonServerImpl() { teardown(); }
 
@@ -61,6 +62,8 @@ void teardown()
       _server = nil;
     }
     _serverCtx = NULL;
+    _failed = false;
+    _logged = false;
   }
 
   void setName(const QString& name)
@@ -87,14 +90,25 @@ void publish(GLuint sourceFbo, int w, int h, const QString& name)
 
       if (_server == nil)
       {
+        if (_failed)
+          return; // Already failed on this context; don't retry every frame.
+
         _server = [[SyphonOpenGLServer alloc] initWithName:qStringToNS(name)
                                                    context:cgl
                                                    options:nil];
         if (_server == nil)
+        {
+          _failed = true;
+          NSLog(@"[SyphonOutput] SyphonOpenGLServer init FAILED for context %p "
+                @"(legacy OpenGL output may be unsupported on this GPU).", cgl);
           return;
+        }
         _serverCtx = cgl;
+        NSLog(@"[SyphonOutput] server started: %@ context %p", qStringToNS(name), cgl);
       }
 
+      glGetError(); // clear any pre-existing error
+
       // Bind the server's FBO and blit our composition into it. A same-size
       // blit from the (multisampled) widget FBO resolves MSAA in one step.
       if ([_server bindToDrawFrameOfSize:NSMakeSize(w, h)])
@@ -108,13 +122,27 @@ void publish(GLuint sourceFbo, int w, int h, const QString& name)
         glBindFramebufferEXT(GL_READ_FRAMEBUFFER_EXT, (GLuint) prevRead);
 
         [_server unbindAndPublish]; // restores the previously-bound FBO + flushes
+
+        if (!_logged)
+        {
+          _logged = true;
+          NSLog(@"[SyphonOutput] first publish %dx%d hasClients=%d glError=0x%x",
+                w, h, (int) [_server hasClients], (unsigned) glGetError());
+        }
+      }
+      else if (!_logged)
+      {
+        _logged = true;
+        NSLog(@"[SyphonOutput] bindToDrawFrameOfSize FAILED at %dx%d", w, h);
       }
     }
   }
 
 private:
   SyphonOpenGLServer* _server;
   CGLContextObj       _serverCtx; // context the server was created with
+  bool                _failed;    // init failed on _serverCtx; stop retrying
+  bool                _logged;     // one-shot diagnostics
 };
 
 // ---------------------------------------------------------------------------

src/gui/MainWindow.cpp

@@ -2248,8 +2248,9 @@ void MainWindow::createActions()
   connect(displayTestSignalAction, SIGNAL(toggled(bool)), outputWindow, SLOT(setDisplayTestSignal(bool)));
 //  connect(displayTestSignalAction, SIGNAL(toggled(bool)), this, SLOT(update()));
 
-#ifdef HAVE_SYPHON
+#if defined(HAVE_SYPHON) && defined(SYPHON_OUTPUT_EXPERIMENTAL)
   // Publish the output as a Syphon server (opt-in, macOS only).
+  // EXPERIMENTAL / DISABLED — see the SYPHON_OUTPUT_EXPERIMENTAL note in src/src.pri.
   publishSyphonOutputAction = new QAction(tr("&Publish Syphon Output"), this);
   publishSyphonOutputAction->setToolTip(tr("Publish the output composition as a Syphon server other apps can receive"));
   publishSyphonOutputAction->setIconVisibleInMenu(false);
@@ -2484,7 +2485,7 @@ void MainWindow::createMenus()
   viewMenu->addSeparator();
   viewMenu->addAction(outputFullScreenAction);
   viewMenu->addAction(displayTestSignalAction);
-#ifdef HAVE_SYPHON
+#if defined(HAVE_SYPHON) && defined(SYPHON_OUTPUT_EXPERIMENTAL)
   viewMenu->addAction(publishSyphonOutputAction);
 #endif
   viewMenu->addAction(displayControlsAction);

src/gui/OutputGLCanvas.cpp

@@ -78,10 +78,11 @@ void OutputGLCanvas::setSyphonServerName(const QString& name)
 
 void OutputGLCanvas::drawForeground(QPainter *painter , const QRectF &rect)
 {
-#ifdef HAVE_SYPHON
+#if defined(HAVE_SYPHON) && defined(SYPHON_OUTPUT_EXPERIMENTAL)
   // Publish the clean composition (background + mappings, no editing overlays or
   // test signal) to Syphon before the foreground is drawn. drawForeground runs
   // after the background and all items, so the framebuffer holds the full frame.
+  // DISABLED — see the SYPHON_OUTPUT_EXPERIMENTAL note in src/src.pri.
   if (_syphonOutput.isEnabled())
   {
     painter->beginNativePainting();

src/src.pri

@@ -55,6 +55,15 @@ macx {
   syphon_framework.path = Contents/Frameworks
   QMAKE_BUNDLE_DATA += syphon_framework
 
+  # Syphon OUTPUT (publishing MapMap's output as a Syphon server) is EXPERIMENTAL
+  # and DISABLED by default: SyphonOpenGLServer cannot create its IOSurface
+  # texture in MapMap's legacy-OpenGL-over-Metal context on Apple Silicon (it
+  # floods "cannot create texture, Metal texture cache was released" and never
+  # publishes). The implementation is kept (SyphonOutput / SyphonServerImpl.mm +
+  # the OutputGLCanvas hook + the "Publish Syphon Output" menu item) but compiled
+  # out. Uncomment to build it back in for development. Tracked on the roadmap.
+  # DEFINES += SYPHON_OUTPUT_EXPERIMENTAL
+
   # With Xcode Tools > 1.5, to reduce the size of your binary even more:
   # LIBS += -dead_strip
   # This tells qmake not to put the executable inside a bundle.