Hi Terry, Good to hear that you've narrowed the problem down to the view dependent case. Without diving into the code and testing it with an app that reproduces the problem I can't add much in the way of specific suggestions.
One thing I've wondered about doing for a while now is to simplify osgText so that the view dependent code is done using manipulation of the modelview matrix rather than computing new values of the vertex positions of the quads as is done right now. The code present holds a multi-buffer of vertex positions of the quads, with a set of positions per view, this code original existed to help handle tens of thousands of text labels on a Onyx system when we had to optimize as much as possible to get the performance required. Nearly a decade of improvements in computers has occurred since then so I don't think the same performance constraints really need to hold back our implementation to being more complicated than it need be. So.... I'm inclined to throw out the multi-buffering and all the complicated updates and move the code to just having a single set of vertices for the quads and then computing the modelview matrix required to align and scale the text labels as required. This simplifies the code and should make it easier to track down problems. It won't directly solve the bounding volume issue with view dependent text labels, but hopefully it'd make it easier to come up with a scheme that works solidly. Robert. On Fri, Mar 26, 2010 at 7:20 AM, Terry Welsh <[email protected]> wrote: > Tracked it down, sort of. Using setAxisAlignment(TextBase::SCREEN) > causes my Text to be culled out sometimes when it shouldn't be. Other > axis alignment modes that have _autoRotateToScreen set to false appear > to work. The Text seems to first appear when some other type of > drawable becomes a sibling in the scene graph structure. So I can > work around the problem now. However, I still can't pinpoint the > exact logic that's causing the Text to be culled improperly. > -- > Terry Welsh / mogumbo 'at' gmail.com > www.reallyslick.com / www.mogumbo.com _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
