[osg-users] OSG + QT and QTabWidget: Disappearing scene graph
Hi, I am trying to build a Qt application with multiple independent OSG scene graphs, each of which in it's own tab in a QTabWidget. I am using the osgViewer::Viewer (not osgViewer::CompositeViewer) version of the adapter widget from the osgviewerQT example. Each tab has an instance of the adapter widget managing it's scene graph. When the application has more than one tabs and when I try to close one of them, sometimes the scene graph in the other tab may disappear, but I can still pick a node in the scene graph. Some people fixed a similar situation by sharing/not sharing the graphics context among the widgets, but none of the solutions that people suggested for the situations fix my problem. I wonder if I should use a different approach for the OSG + QT integration or if I need to do something particular to the graphics context. I appreciate all of your suggestions. Thank you! Cheers, Angus Lau -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=34464#34464 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] How should I organize the scene graph to handle 2 million points and lines?
Hi, Thank you for both of your help. It seems that PagedLOD is what I need to use to reduce CPU memory usage. I have tried to use PagedLOD briefly before, but I am not clear how I can make PagedLOD unload the unused child nodes once those child nodes are loaded. It seems that my PagedLOD nodes do not remove the nodes once it creates the child nodes. Could you please give me some explanation about the proper way of using it?? Thank you! Cheers, Angus -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=19123#19123 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] How should I organize the scene graph to handle 2 million points and lines?
Hi, Thank you for your suggestions! I think the scribe effect is probably what I want for selection. You mentioned something about unreferencing data on the CPU side once it is uploaded. I am quite interested in this. Could you please give me more details? Honestly speaking, the 2 million points and lines are probably not the largest dataset I will encounter. During the last few days, I discovered that my viewer probably has an acceptable performance, but the large amount of memory that it uses is probably the main issue I need to deal with. If there are some ways that can reduce the size of the scene graph or cache inactive part of the scene graph on disk, I would like to give them a try. Thank you! Cheers, Angus -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=19076#19076 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] How should I organize the scene graph to handle 2 million points and lines?
Hi, I am trying to build a viewer that can display millions of points and lines. How should I organize or structure the scene graph to maximize the performance and minimize the memory usage? Thank you! Cheers, Angus -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=18832#18832 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] How should I organize the scene graph to handle 2 million points and lines?
Hi, Thank you for your help. I would like to show as many lines and points as possible at one time. Since some lines and points are clustered together, I am thinking about using LOD, PagedLOD, Impostor, or something similar to make culling and drawing take less time, but my viewer is actually an inspection tool. It is better to show as much details as possible. My viewer needs to support Pan, Zoom, Orbit, and Select. The position of the lines and points are static but their colors are used for selection. My viewer allows the user to select one or more lines and points by changing their color. Right now, I am grouping chunks of lines in some osg::Geometry nodes and storing their colors in the color arrays. When the user select a line, for example, I will change the color of the line in the color array. Even though the grouping improve the viewer performance a lot, unrelated lines or points are now grouped together, making the scene graph inflexible to be used in other ways. Also, is changing the color to show the selection a bad idea? Other ways of showing the selected lines and points are fine, as long as I can improve the performance and the memory usage. The lines and points also take up a lot of memory ( 1GB) in the scene graph. Large memory allocation may also be the cause of a long loading time for the data. Is there a way to reduce the memory usage for the scene graph? Thank you! Cheers, Angus -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=18887#18887 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
