Robert, Thank you for your reply.
On Wed, Sep 11, 2013 at 8:27 AM, Robert Osfield <[email protected]> wrote: > Normally one should ever need to worry about constructing or destructing the > DatabasePager Thank you. My preference is to never think about the DatabasePager. Since I use multiple views, at a minimum I must be concerned with a function called DatabasePager::setUnrefImageDataAfterApplyPolicy. > osgViewer::Scene is used internally by osgViewer to manage one DatabasePager > per scene graph. The Scene object will be shared automatically between > Views if you assign the same Node pointer hen you call View::setSceneData. > This sharing is done automatically for you. When a Scene object is > destructed it's DatabasePager will be destructed if no other references to > it exist. Is this a correct understanding: If I am running a scene with 2 viewers, and I remove both of those viewers but not the scene, then the DatabasePager is destroyed. Then, if I later add attach the scene to a new viewer, the DatabasePager is re-created. All this happens behind the scenes and I need not be worried about it. > If you have multiple Views that you should be using CompositeViewer, not > multiple Viewer. Thank you. You're the second person to mention this to me today so it must be true! However, please consider: 1. Inexplicably when I render my scene with a CompositeViewer, adding and removing views during runtime, my renderings turn "purple". By "purple" i mean that none of my objects are rendered! (osgEarth terrain and imagery). What's more (and you might not believe me on this point): when I use multiple viewers on the same graph (without using CompositeViewer) then I do not suffer this problem! 2. I can understand if nobody wants to provide an answer to this question, but I'd like to know: What are the repercussions of running multiple viewers on one scene when the "correct" approach is to run a single CompositeViewer w/multiple views on one scene? > If you are creating and destroying views regularly then you are probably > best to enable/disable them by setting the View's master Camera's NodeMask > to 0x0 and back to 0xffffffff, as this will switch off rendering but keep > the backend around ready to be re-enabled. I understand. While not impossible, a design such as this will require a re-architecting of my code as at present I have no idea how many viewers, if any, will want to look at my scene. Thank you for your help, I appreciate learning about these technical under-the-hood aspects (vs just "here's what you need to type to get it to work"), Chris _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
