Re: [osg-users] Qt + non-continuous draw + pagedLOD: Random loss of detail??
Thanks for the additions Maciej, the changes have missed the OpenSceneGraph-2.6 branch/feature freeze so will have to be merged once 2.6 is out. On Mon, Aug 4, 2008 at 1:51 PM, Maciej Krol [EMAIL PROTECTED] wrote: Hi all, I have implement frame based expiration of PagedLOD children. I will send it to osg-submissions as well. New attribute DatabasePager::_expiryFrames sets number of frames a PagedLOD child is kept in memory. The attribute is set with DatabasePager::setExpiryFrames method or OSG_EXPIRY_FRAMES environmental variable. New attribute PagedLOD::PerRangeData::_frameNumber contains frame number of last cull traversal. Children of PagedLOD are expired when time _AND_ number of frames since last cull traversal exceed OSG_EXPIRY_DELAY _AND_ OSG_EXPIRY_FRAMES respectively. By default OSG_EXPIRY_FRAMES = 1 which means that nodes from last cull/rendering traversal will not be expired even if last cull time exceeds OSG_EXPIRY_DELAY. Setting OSG_EXPIRY_FRAMES = 0 revokes previous behaviour of PagedLOD. Setting OSG_EXPIRY_FRAMES 0 fixes problems of children reloading in lazy rendering applications. Required behaviour is achieved by manipulating OSG_EXPIRY_DELAY and OSG_EXPIRY_FRAMES together. Two interface changes are made: DatabasePager::updateSceneGraph(double currentFrameTime) is replaced by DatabasePager::updateSceneGraph(const osg::FrameStamp frameStamp). The previous method is in #if 0 clause in the header file. Robert, decide if You want to include it. PagedLOD::removeExpiredChildren(double expiryTime, NodeList removedChildren) is deprecated (warning is printed), when subclassing use PagedLOD::removeExpiredChildren(double expiryTime, int expiryFrame, NodeList removedChildren) instead. Regards, Maciej Krol 2008/8/3 Robert Osfield [EMAIL PROTECTED] Hi John, As others have pointed out, what you are seeing is the removal of expired subgraphs. The DatabasePager is built around continuous update of the scene graph - both for loading of new subgraphs, compiling of subgraphs, merging of subgraphs and removal of expired subgraphs. As such paging databases aren't appropriate to non continuous updated apps, you could fudge things by upping the expiry delay on the DatabasePager. Doing periodic renders of the scene would also allow things to tick along. Robert. On Wed, Jul 30, 2008 at 1:39 PM, John Vidar Larring [EMAIL PROTECTED] wrote: Hi all, Background: --- In our application the user can set up scenes ( or sequences as we call them) for playback on a timeline (e.g. seq.1 - transition - seg.2 - transition ... seq.N). Some scenes are too complex to render real-time and are recorded to movies before playback. Hence, when scenes are edited by the user all scenes are redrawn as needed rather than continuously to avoid sluggish GUI response. Problem: _Sometimes_ when the scene is redrawn in edit mode (i.e. redraw only if needed), the pagedLOD DB (osgTerrain) drops to the lowest detail level (Ref. osg_original.jpg and osg_problem.jpg). This behavior seems to appear at randomly. In playback mode (i.e. when frame rate is constant) the problem never occurs. Reproduce / Code example: -- The problem has been reproduces in a small test program (osgtest_source_code.tgz) derived from the osgviewerQT example (since we are using Qt 4.x in our application). To reproduce: run the compiled application: 'osgtest -t your osgTerrain db' . To trigger refreshes, occlude parts of the window with another window. The problem typically reveals itself when at a redraw or when the window looses focus (be patient, since this happens randomly it may take some time before the problem occurs). Since I'm still quite new to OSG, I'm not sure where to look for a solution. Hopefully someone will spot the obvious error in the sample code. Any advice is highly appreciated. Versions: - OSG svn rev 8700 Qt 4.2.3 Best regards, John Larring -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- Regards, Maciej Krol ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Qt + non-continuous draw + pagedLOD: Random loss of detail??
Hi John, As others have pointed out, what you are seeing is the removal of expired subgraphs. The DatabasePager is built around continuous update of the scene graph - both for loading of new subgraphs, compiling of subgraphs, merging of subgraphs and removal of expired subgraphs. As such paging databases aren't appropriate to non continuous updated apps, you could fudge things by upping the expiry delay on the DatabasePager. Doing periodic renders of the scene would also allow things to tick along. Robert. On Wed, Jul 30, 2008 at 1:39 PM, John Vidar Larring [EMAIL PROTECTED] wrote: Hi all, Background: --- In our application the user can set up scenes ( or sequences as we call them) for playback on a timeline (e.g. seq.1 - transition - seg.2 - transition ... seq.N). Some scenes are too complex to render real-time and are recorded to movies before playback. Hence, when scenes are edited by the user all scenes are redrawn as needed rather than continuously to avoid sluggish GUI response. Problem: _Sometimes_ when the scene is redrawn in edit mode (i.e. redraw only if needed), the pagedLOD DB (osgTerrain) drops to the lowest detail level (Ref. osg_original.jpg and osg_problem.jpg). This behavior seems to appear at randomly. In playback mode (i.e. when frame rate is constant) the problem never occurs. Reproduce / Code example: -- The problem has been reproduces in a small test program (osgtest_source_code.tgz) derived from the osgviewerQT example (since we are using Qt 4.x in our application). To reproduce: run the compiled application: 'osgtest -t your osgTerrain db' . To trigger refreshes, occlude parts of the window with another window. The problem typically reveals itself when at a redraw or when the window looses focus (be patient, since this happens randomly it may take some time before the problem occurs). Since I'm still quite new to OSG, I'm not sure where to look for a solution. Hopefully someone will spot the obvious error in the sample code. Any advice is highly appreciated. Versions: - OSG svn rev 8700 Qt 4.2.3 Best regards, John Larring -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Qt + non-continuous draw + pagedLOD: Random loss of detail??
Hi all, I have the same problem in our digital content creation tool. IMHO the plausible solution would be to expire the nodes after certain number of frames rather than period of time. This would require changes in the database pager. It shall be possible to select expiration mode - time based or frame based (i.e. osgDB::setExpiryMode). I will think about implementation details this weekend. Regards, Maciej Krol 2008/7/31 Jakob Ruhe [EMAIL PROTECTED] Hi John! I also have these kind of problems when I use lazy rendering which is the way I want it to be done in my application. These methods may help you: osgDB::setExpiryDelay PagedLOD::setNumChildrenThatCannotBeExpired You can also override these virtual methods to fine tune what you want to do: osgDB::removeExpiredSubgraphs PagedLOD::removeExpiredChildren I hope it can help you in your case even though these are not any good permanent solutions for any lazy rendering app.. /Jakob Ruhe 2008/7/30 Glenn Waldron [EMAIL PROTECTED]: John, I have run into the same issue. PagedLOD children expire after a certain period of time (default is something like 5 seconds?) If a PagedLOD child has not been visited in the last N seconds, the pager will discard it and revert to a lower LOD. OSG updates the time-last-visited during the cull traversal in order to check for expiration. So, if you are not continuously running the frame loop, PagedLOD's will think their children have expired and will drop to the lowest LOD. I used to refer to the technique you're using as lazy rendering (i.e. only render a frame when something has changed) ... try searching the archives ... but at the time I never did find a good way to do this in OSG without confusing the pager. Glenn -- Glenn Waldron : Pelican Mapping : http://pelicanmapping.com : +1.703.652.4791 On Wed, Jul 30, 2008 at 8:39 AM, John Vidar Larring [EMAIL PROTECTED] wrote: Hi all, Background: --- In our application the user can set up scenes ( or sequences as we call them) for playback on a timeline (e.g. seq.1 - transition - seg.2 - transition ... seq.N). Some scenes are too complex to render real-time and are recorded to movies before playback. Hence, when scenes are edited by the user all scenes are redrawn as needed rather than continuously to avoid sluggish GUI response. Problem: _Sometimes_ when the scene is redrawn in edit mode (i.e. redraw only if needed), the pagedLOD DB (osgTerrain) drops to the lowest detail level (Ref. osg_original.jpg and osg_problem.jpg). This behavior seems to appear at randomly. In playback mode (i.e. when frame rate is constant) the problem never occurs. Reproduce / Code example: -- The problem has been reproduces in a small test program (osgtest_source_code.tgz) derived from the osgviewerQT example (since we are using Qt 4.x in our application). To reproduce: run the compiled application: 'osgtest -t your osgTerrain db' . To trigger refreshes, occlude parts of the window with another window. The problem typically reveals itself when at a redraw or when the window looses focus (be patient, since this happens randomly it may take some time before the problem occurs). Since I'm still quite new to OSG, I'm not sure where to look for a solution. Hopefully someone will spot the obvious error in the sample code. Any advice is highly appreciated. Versions: - OSG svn rev 8700 Qt 4.2.3 Best regards, John Larring -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Qt + non-continuous draw + pagedLOD: Random loss of detail??
Hi John! I also have these kind of problems when I use lazy rendering which is the way I want it to be done in my application. These methods may help you: osgDB::setExpiryDelay PagedLOD::setNumChildrenThatCannotBeExpired You can also override these virtual methods to fine tune what you want to do: osgDB::removeExpiredSubgraphs PagedLOD::removeExpiredChildren I hope it can help you in your case even though these are not any good permanent solutions for any lazy rendering app.. /Jakob Ruhe 2008/7/30 Glenn Waldron [EMAIL PROTECTED]: John, I have run into the same issue. PagedLOD children expire after a certain period of time (default is something like 5 seconds?) If a PagedLOD child has not been visited in the last N seconds, the pager will discard it and revert to a lower LOD. OSG updates the time-last-visited during the cull traversal in order to check for expiration. So, if you are not continuously running the frame loop, PagedLOD's will think their children have expired and will drop to the lowest LOD. I used to refer to the technique you're using as lazy rendering (i.e. only render a frame when something has changed) ... try searching the archives ... but at the time I never did find a good way to do this in OSG without confusing the pager. Glenn -- Glenn Waldron : Pelican Mapping : http://pelicanmapping.com : +1.703.652.4791 On Wed, Jul 30, 2008 at 8:39 AM, John Vidar Larring [EMAIL PROTECTED] wrote: Hi all, Background: --- In our application the user can set up scenes ( or sequences as we call them) for playback on a timeline (e.g. seq.1 - transition - seg.2 - transition ... seq.N). Some scenes are too complex to render real-time and are recorded to movies before playback. Hence, when scenes are edited by the user all scenes are redrawn as needed rather than continuously to avoid sluggish GUI response. Problem: _Sometimes_ when the scene is redrawn in edit mode (i.e. redraw only if needed), the pagedLOD DB (osgTerrain) drops to the lowest detail level (Ref. osg_original.jpg and osg_problem.jpg). This behavior seems to appear at randomly. In playback mode (i.e. when frame rate is constant) the problem never occurs. Reproduce / Code example: -- The problem has been reproduces in a small test program (osgtest_source_code.tgz) derived from the osgviewerQT example (since we are using Qt 4.x in our application). To reproduce: run the compiled application: 'osgtest -t your osgTerrain db' . To trigger refreshes, occlude parts of the window with another window. The problem typically reveals itself when at a redraw or when the window looses focus (be patient, since this happens randomly it may take some time before the problem occurs). Since I'm still quite new to OSG, I'm not sure where to look for a solution. Hopefully someone will spot the obvious error in the sample code. Any advice is highly appreciated. Versions: - OSG svn rev 8700 Qt 4.2.3 Best regards, John Larring -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Qt + non-continuous draw + pagedLOD: Random loss of detail??
John, I have run into the same issue. PagedLOD children expire after a certain period of time (default is something like 5 seconds?) If a PagedLOD child has not been visited in the last N seconds, the pager will discard it and revert to a lower LOD. OSG updates the time-last-visited during the cull traversal in order to check for expiration. So, if you are not continuously running the frame loop, PagedLOD's will think their children have expired and will drop to the lowest LOD. I used to refer to the technique you're using as lazy rendering (i.e. only render a frame when something has changed) ... try searching the archives ... but at the time I never did find a good way to do this in OSG without confusing the pager. Glenn -- Glenn Waldron : Pelican Mapping : http://pelicanmapping.com : +1.703.652.4791 On Wed, Jul 30, 2008 at 8:39 AM, John Vidar Larring [EMAIL PROTECTED]wrote: Hi all, Background: --- In our application the user can set up scenes ( or sequences as we call them) for playback on a timeline (e.g. seq.1 - transition - seg.2 - transition ... seq.N). Some scenes are too complex to render real-time and are recorded to movies before playback. Hence, when scenes are edited by the user all scenes are redrawn as needed rather than continuously to avoid sluggish GUI response. Problem: _Sometimes_ when the scene is redrawn in edit mode (i.e. redraw only if needed), the pagedLOD DB (osgTerrain) drops to the lowest detail level (Ref. osg_original.jpg and osg_problem.jpg). This behavior seems to appear at randomly. In playback mode (i.e. when frame rate is constant) the problem never occurs. Reproduce / Code example: -- The problem has been reproduces in a small test program (osgtest_source_code.tgz) derived from the osgviewerQT example (since we are using Qt 4.x in our application). To reproduce: run the compiled application: 'osgtest -t your osgTerrain db' . To trigger refreshes, occlude parts of the window with another window. The problem typically reveals itself when at a redraw or when the window looses focus (be patient, since this happens randomly it may take some time before the problem occurs). Since I'm still quite new to OSG, I'm not sure where to look for a solution. Hopefully someone will spot the obvious error in the sample code. Any advice is highly appreciated. Versions: - OSG svn rev 8700 Qt 4.2.3 Best regards, John Larring -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
