HI Julien, Are you still talking about the same VAO implementation you original proposed last year?
I tested this and decided against it. In testing performance and comparing it against my own non sharing VAO implementation the later performance far better for a range of models that I have to test against. The biggest bag in performance between the two was on very large models such as city models where there we are large number of objects. Even you unit test case performed better with my implementation. I found the CPU overhead in your implementations swamped any other theoretical performance improvements. The official VAO implementation that we now have is part of master, performs well, looks to be pretty reliable. As previously discussed it may be possible to adapt this implementation to share the osg::VertexArrayState object in cases where osg::Geometry share their arrays. However, such changes would have to justified by a real performance improvement on real complete data. Robert. On 5 February 2017 at 23:34, Julien Valentin <[email protected]> wrote: > Hi all, > Excuse me to return on an old debate but I can't achieve VAO sharing with the > current design...I really need an easy way for drawing with basevertices > > To argue on the utility of VAO sharing among geometries, and (so on the > replacement DrawElements to DrawElementBaseVertex as draw submission command): > > 1)GPU Pro 4 : Evaluating drawcall cpu overhead and GPU Draw Submission > Limitations > https://books.google.fr/books?id=_FnSBQAAQBAJ&pg=PA24&lpg=PA24&dq=cost+of+glbindvertexarray&source=bl&ots=1O1DTprEUD&sig=XBs_GMyYM8em72dF8fWnO3YeRKU&hl=fr&sa=X&ved=0ahUKEwiunsa8mMvOAhXDWRoKHXwuBN4Q6AEISzAE#v=onepage&q=cost%20of%20glbindvertexarray&f=true > 2)Performances of my VAO proposal have conforted me in facts vaos should be > shared and draw calls should be submitted with basevertex. > 1VAO/Geom DrawCost 4 > shared VAOs DrawCost 2 > (My VAO proposal contains a little overhead that can be easily deported to a > NodeVisitor) > > I would like other sentiments on the subject > > > Cheers > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=70109#70109 > > > > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
