Hi Patrick, If you want to decouple a slave Camera from the master simply use reference frame to absolute via Camera::setReferenceFrame(osg::Camera::ABSOLUTE_RF), then any settings of the slave Camera's view and projection matrix won't be affected by the master Camera's settings. See the osghud example for this in action.
Robert. On 16 March 2014 18:46, Patrick Keenan <[email protected]> wrote: > Hello, > > I am trying to use a slave camera in my viewer to follow a node and render > what it sees to a pixel buffer, then I convert the images to cv::Mat to do > image processing on them. It is a simulation of a robot setup were the > camera is rigidly attached to the robot. I have managed to get it mostly > working using advice from the forum and the osgscreencapture example but am > stuck on a strange little thing. I gather that I need to manually update > the _viewOffset of the slave each frame so that it can move around with the > robot. > > > Code: > > std::int64_t M_OSG_viewer::Draw(void) > { > _last_draw_time_us = _last_draw_timer.Get_elapsed_us(); > if(_has_slave_cam) > { > osg::View::getSlave(0)._viewOffset = > osgViewer::Viewer::getCamera()->getInverseViewMatrix() > > *_slave_cam_xform->getMatrix() > > *osg::Matrix::rotate( -osg::PI/2.0, 1.0, 0.0, 0.0 ); > } > if(_last_draw_time_us > 8333) > { > osgViewer::Viewer::getViewerBase()->frame(); > _last_draw_timer.Restart(); > } > return _last_draw_time_us; > } > > > > > > When I do this it does work but if I use the mouse to manipulate the view > of the scene it will move/shift the images from the PBO a bit, that is, it > will not stay still. Does anyone know why this would be, is it just round > off error? Is there a better approach? > > Thanks, Patrick > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=58615#58615 > > > > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >
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