Hi all -- I'd like to see how members of the community are handling this fairly common OSG problem. Imagine that your app needs to modify the scene graph based on the viewpoint location, view frustum, distance to the viewpoint, etc. This information is not guaranteed to be available, accurate, or up-to-date until the _end_ of the update phase, right? Typically this info is only available from the CullVisitor. But it's too late to modify the scene graph during cull -- it's not thread safe. So, how does your app handle this situation? OSG itself needs to handle this situation in a few places. AutoTransform, Billboard, LOD, and screen-oriented text, just to name a few. I believe OSG handles this with a 1-frame latency with these classes (obtains the values during cull but updates the scene graph during update of the next frame), but haven't looked at the code in a long time. Another way to do this would be to query the viewpoint location / view frustum during update and modify the scene graph based on those values, even though those values could still change before the start of cull-draw. But I'm interested in hearing other ideas on how to handle this issue. Thanks in advance for any feedback. Paul Martz Skew Matrix Software LLC http://www.skew-matrix.com <http://www.skew-matrix.com/> +1 303 859 9466
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