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Multiple NSWindows for openFrameworks
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With ofxNSWindower, you can create multiple OpenGL windows with a shared context, to draw your openFrameworks apps. ofxNSWindower does not use GLUT, so an openFrameworks app has a slightly different design, but allows for greater flexibility. Features using ofxNSWindower are:

  • Multiple Windows
  • Mouse Scrolled Events
  • Easy Mac/Cocoa GUIs


After the changes made in v0.2, a small patch has to be made to oF. To run this, double click on 'of_patch' in the root directory. Make sure that the addon is in the correct directory when you do this. If you see errors, read the bottom of this file.

ofxNSWindower, implemented as a singleton class, handles all the windows. Each window has an app (what it draws) and also other attributes like a name and window options. To add a window you could do the following:

ofxNSWindower::instance()->addWindow(new testApp());

Which is roughly equivalent to ofRunApp(new testApp());

Additionally, you can give the window a name, options for the window and a frame rate:

ofxNSWindower::instance()->addWindow(new testApp(), "hello", NSTitledWindowMask, 60);

hello is the name of the window, NSTitledWindowMask is the window option (more on those later) and 60 is the frame rate. If 0 is given as a frame rate, then the frame rate will match the refresh rate of the screen.

Window options can be seen here. These can be combined using a boolean OR (|). The default is NSTitledWindowMask, so there is a title bar but no buttons.

If a name is not given then the window is assigned a random name which is a number between 0 and 1000. The default frame rate is 30.

To access testApp you can use getAppPtr(), in a very similar manner to normal openFrameworks apps, only that here you need to pass the name of the window to get the right app:

testApp *saverApp = (testApp*) ofxNSWindower::instance()->getAppPtr("hello");

Apps do not subclass ofBaseApp, but ofxNSWindowApp. This is very similar to ofBaseApp, but has a few differences. These are:

  • mouseScrolled event is added
  • windowResized() & gotMessage() is removed
  • exit() is now close()

Also, a few of the openFrameworks functions now will not work, such as ofGetWidth(). To query and set window properties use normal oF functions, the results of these functions will vary between windows, provided the above (and below) patch has been applied.


The architecture of an ofxNSWindower app is quite different to a standard openFrameworks app using GLUT. Apps are not created in main(), but inside the application delegate, which is instantiated from the main .xib file. See the examples for more details.


When I first created this addon I wanted to do so without needing to modify the oF core. Issue #1 hightlighted problems that couldn't be resolved without a modification. If you want to add these manually, then add:

void ofSetAppWindow(ofPtr<ofAppBaseWindow> windowPtr); to ofAppRunner.h

void ofSetAppWindow(ofPtr<ofAppBaseWindow> windowPtr) { window = windowPtr; } to ofAppRunner.cpp

These two files can be found in libs/openFrameworks/app

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