OpenGL: Fixed a crash in Cubase/WaveLab when OpenGL is used in a plug-ins editor

modules/juce_gui_basics/native/juce_mac_NSViewComponentPeer.mm

@@ -61,7 +61,7 @@ static NSRect flippedScreenRect (NSRect r) noexcept
 }
 
 #if JUCE_MODULE_AVAILABLE_juce_opengl
-void componentPeerAboutToBeRemovedFromScreen (ComponentPeer&);
+void componentPeerAboutToChange (ComponentPeer&, bool);
 #endif
 
 //==============================================================================
@@ -173,7 +173,10 @@ public:
         setOwner (view, nullptr);
 
         if ([view superview] != nil)
+        {
+            redirectWillMoveToWindow (nullptr);
             [view removeFromSuperview];
+        }
 
         [view release];
 
@@ -668,8 +671,8 @@ public:
     void redirectWillMoveToWindow (NSWindow* newWindow)
     {
        #if JUCE_MODULE_AVAILABLE_juce_opengl
-        if ([view window] == window && newWindow == nullptr)
-            componentPeerAboutToBeRemovedFromScreen (*this);
+        if ([view window] == window)
+            componentPeerAboutToChange (*this, (newWindow == nullptr));
        #else
         ignoreUnused (newWindow);
        #endif

modules/juce_opengl/native/juce_OpenGL_osx.h

@@ -247,7 +247,7 @@ bool OpenGLHelpers::isContextActive()
 }
 
 //==============================================================================
-void componentPeerAboutToBeRemovedFromScreen (ComponentPeer& peer)
+void componentPeerAboutToChange (ComponentPeer& peer, bool shouldSuspend)
 {
     Array<Component*> stack;
     stack.add (&peer.getComponent());
@@ -262,6 +262,6 @@ void componentPeerAboutToBeRemovedFromScreen (ComponentPeer& peer)
                 stack.add (child);
 
         if (OpenGLContext* context = OpenGLContext::getContextAttachedTo (comp))
-            context->detach();
+            context->overrideCanBeAttached (shouldSuspend);
     }
 }

modules/juce_opengl/opengl/juce_OpenGLContext.cpp

@@ -664,16 +664,9 @@ public:
 
     void detach()
     {
-        stopTimer();
-
         Component& comp = *getComponent();
 
-       #if JUCE_MAC
-        [[(NSView*) comp.getWindowHandle() window] disableScreenUpdatesUntilFlush];
-       #endif
-
-        if (CachedImage* const oldCachedImage = CachedImage::get (comp))
-            oldCachedImage->stop(); // (must stop this before detaching it from the component)
+        stop();
 
         comp.setCachedComponentImage (nullptr);
         context.nativeContext = nullptr;
@@ -732,12 +725,22 @@ public:
     }
    #endif
 
+    void update()
+    {
+        Component& comp = *getComponent();
+
+        if (canBeAttached (comp))
+            start();
+        else
+            stop();
+    }
+
 private:
     OpenGLContext& context;
 
-    static bool canBeAttached (const Component& comp) noexcept
+    bool canBeAttached (const Component& comp) noexcept
     {
-        return comp.getWidth() > 0 && comp.getHeight() > 0 && isShowingOrMinimised (comp);
+        return (! context.overrideCanAttach) && comp.getWidth() > 0 && comp.getHeight() > 0 && isShowingOrMinimised (comp);
     }
 
     static bool isShowingOrMinimised (const Component& c)
@@ -763,10 +766,35 @@ private:
                                                              context.openGLPixelFormat,
                                                              context.contextToShareWith);
         comp.setCachedComponentImage (newCachedImage);
-        newCachedImage->start(); // (must wait until this is attached before starting its thread)
-        newCachedImage->updateViewportSize (true);
 
-        startTimer (400);
+        start();
+    }
+
+    void stop()
+    {
+        stopTimer();
+
+        Component& comp = *getComponent();
+
+       #if JUCE_MAC
+        [[(NSView*) comp.getWindowHandle() window] disableScreenUpdatesUntilFlush];
+       #endif
+
+        if (CachedImage* const oldCachedImage = CachedImage::get (comp))
+            oldCachedImage->stop(); // (must stop this before detaching it from the component)
+    }
+
+    void start()
+    {
+        Component& comp = *getComponent();
+
+        if (CachedImage* const cachedImage = CachedImage::get (comp))
+        {
+            cachedImage->start(); // (must wait until this is attached before starting its thread)
+            cachedImage->updateViewportSize (true);
+
+            startTimer (400);
+        }
     }
 
     void timerCallback() override
@@ -784,7 +812,8 @@ OpenGLContext::OpenGLContext()
       imageCacheMaxSize (8 * 1024 * 1024),
       renderComponents (true),
       useMultisampling (false),
-      continuousRepaint (false)
+      continuousRepaint (false),
+      overrideCanAttach (false)
 {
 }
 
@@ -1024,6 +1053,17 @@ void OpenGLContext::execute (OpenGLContext::AsyncWorker::Ptr workerToUse, bool s
         jassertfalse; // You must have attached the context to a component
 }
 
+void OpenGLContext::overrideCanBeAttached (bool newCanAttach)
+{
+    if (overrideCanAttach != newCanAttach)
+    {
+        overrideCanAttach = newCanAttach;
+
+        if (Attachment* a = attachment)
+            a->update();
+    }
+}
+
 //==============================================================================
 struct DepthTestDisabler
 {

modules/juce_opengl/opengl/juce_OpenGLContext.h

@@ -308,7 +308,7 @@ private:
     void* contextToShareWith;
     OpenGLVersion versionRequired;
     size_t imageCacheMaxSize;
-    bool renderComponents, useMultisampling, continuousRepaint;
+    bool renderComponents, useMultisampling, continuousRepaint, overrideCanAttach;
 
     //==============================================================================
     struct AsyncWorker : ReferenceCountedObject
@@ -328,6 +328,10 @@ private:
         JUCE_DECLARE_NON_COPYABLE(AsyncWorkerFunctor)
     };
 
+    //==============================================================================
+    friend void componentPeerAboutToChange (ComponentPeer&, bool);
+    void overrideCanBeAttached (bool);
+
     //==============================================================================
     CachedImage* getCachedImage() const noexcept;
     void execute (AsyncWorker::Ptr, bool);