Hi Lukasz and Robert, sorry, I did not look on the source code, but I have a comment to the Delta[Simulation|Frame]Time. I am using OSG in ON_DEMAND run scheme, e.g. not using 100% CPU and redraw only when needed or when there is animation in the scene (CAD oriented usage model). Usually, I get continual animation only when I rotate model or move the camera (using camera manipulators). What would be the meaning of DeltaFrameTime in such user scenario? Patricularly, the user stops camera movement, watches the static scene for 10 seconds and then starts another camera manipulation. Does it mean that for the start of the second camera manipulation, the first frame will get DeltaFrameTime of 10 seconds? The same issue might be for DeltaSimulationTime (not sure). Getting such big peaks is definitely not something I would like. Similar issue might appear in CONTINUOUS_UPDATE scheme as well when loading big models, and you do not get frame update for, say, 1 second.
John On Tuesday 22 of October 2013 15:59:38 Robert Osfield wrote: > Hi Lukasz, > > I have now done a code review and as things stand don't feel they are > appropriate to merge. > > The problems are that it introduces a DeltaTime property to osg::FrameStamp > but there are two distinct concenpts of time stored by FrameStamp - > SimulationTime and FrameTime and it's not clear what this new property > referrs to. From your implementation I can see it a DeltaFrameTime, > however, normally for simulation work you'd want to use DeltaSimulationTime > so perhaps you haven't spotted this subtle difference. For consistency it > would be required to add a DeltaSimulationTime and DeltaFrameTime, or > perhaps SimulationTimeDelta, FrameTimeDelta would flow better. > > Another missing element is that the FrameStamp values are passed into > shaders via the osg_SimulationTime and osg_FrameTime unifiorms, the code > for this is in osgUtil::SceneView. If we do add the delta's in then it > would make sense to expose them in shaders like we do from SimulationTIme > and FrameTime. > > Robert. _______________________________________________ osg-submissions mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-submissions-openscenegraph.org
