Hi Chris, On Wed, 15 May 2019 at 00:32, Chris Djali <krizdj...@gmail.com> wrote: > I'm investigating using a geometry shader to render multiple shadow map > cascades in one pass in OpenMW. While I've heard conflicting (but mostly > negative) accounts of how much additional performance this can bring, I > reckon it's likely to help, as OpenMW uses a ridiculous quantity of tiny > drawables, causing a ridiculous number of draw calls when RTT passes are > used, and there's no easy batching implementation as user/game scripts can > add, remove, replace and relocate object with no notice. There are solutions > in the works for this, but layered rendering may be low-hanging fruit that > can be done in the meantime.
Both OpenGL and OSG suffer from lots of small grained drawables. so avoiding lots of drawables can be crucial to improving performance. This may be resolvable at the high level in your application with exsiting OSG features, or tackled by subclass from vsg::Drawable or vsg::Geometry to provide a custom drawImplementation() that is able to juggle the dynamic changes in a more lightweight way. For instance if you can keep the vertex arrays pretty constant but add/remove PrimitiveSet in a dynamic way then should be avoid much of the cost of the alternative of lots separate drawables. > Anyway, onto the problem at hand... > > In order to do this, I need to bind a layered depth texture as a render > target. When I looked into doing this in OSG, the two threads I found claimed > it wasn't possible yet, but as they were from a long time ago, it's possible > support has been implemented since them. Can this be done yet? I'd rather not > have to spend a long time investigating only to determine that it's still > impossible. I don't know enough of what you are thinking of to be able to make any suggestions here, it's too open ended. Robert. _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
