ofxOpenSceneGraph ReadMe

by http://stephanmaximilianhuber.com

this small add-on helps OpenFrameworks-code to live side by side with OpenSceneGraph.

Requirements

• OpenSceneGraph from http://openscenegraph.org
• OpenFrameworks 0062 from http://openframeworks.org

Install (OS X only for the moment, should work with linux/win32, too)

• download, configure and install OpenFrameworks
• download and copy this addon into OpenFramworks/addons
• download, configure and install OpenSceneGraph
  • use cmake with the following options: /usr/bin/cmake -G Xcode
    -D OSG_BUILD_FRAMEWORKS:BOOL=1
    -D OSG_WINDOWING_SYSTEM:STRING=Cocoa
    -D OSG_BUILD_PLATFORM_IPHONE:BOOL=0
    -D CMAKE_OSX_ARCHITECTURES:STRING=i386
    -D CMAKE_OSX_SYSROOT:STRING=/Developer/SDKs/MacOSX10.5.sdk .
  • open the xcode-project, build all targets and run the install-target (the run-part is essential!)
• Move the compiled frameworks from OpenSceneGraph to openFrameworks/addons/ofxOpenSceneGraph/lib/osx/frameworks
• Move all plugins from OpenSceneGraph to openFrameworks/addons/ofxOpenSceneGraph/lib/osx/plugins
• Open one of the examples and try to build and run it.

How it works

ofxOpenSceneGraph provides a customized ofAppBaseWindow-class which

• creates an osgViewer::CompositeViewer
• creates an osgViewer::View and register it
• creates an event-handler to forward events from OpenSceneGraph to OpenFrameworks
• creates a CameraPreDrawCallback which calls the draw-function of the OpenFrameworks-app.
• runs the run-loop and calls the update-function of the OpenFrameworks-app.

There's even a ofxOsgApp-class, so you can get the composite-viewer and view from your app-code. Just inherit from ofBaseApp and ofxOsgApp

class myApp : public ofBaseApp, public ofxOsgApp {

};

Caveats

• the OpenFrameworks-draw-routine is called before any drawing is done by OpenSceneGraph. Future versions may implement a postDraw-function which get called after all osg-related drawing.
• the current implementation does funky things when destroying the app-instance, as some OpenFrameworks-objects need an active OpenGL-context when they get destroyed.
• osg's multi-threaded rendering is disabled, as the update and draw-routines of the framework-app may overlap.

Have fun,

Stephan ( me at stephanmaximimilanhuber.com )