StateSet::setRenderingHint is merly a convenience function for setting the bin number and bin name it has no function beyond this.
On 10/4/07, Christophe Medard <[EMAIL PROTECTED]> wrote: > To react to what says Robert, I'm under the impression that renderingHint in > fact isn't used internally, is it ? > Why is there two informations in fact redundant (an order of draw), > renderingHint and binNumber ? > > So if I'm correct, things must only be thought of in 'binNumber' terms. > To react to what says Tim, I'm passing through stateset on group nodes > indeed, but I'm not sure to perfecly understand well what you're saying. > Let's take a over simple example, if I have the following three, what will > be the order of draw ? > > > | > > -------------------------------------------- > | > | > osg::Group "A" > osg::Group "B" > [binNumber = 8] > dft, so binNumber = 0 > | > ------------------------------------------------ > | | > | > osg::Geode "C" osg::Geode "D" osg::Geode "E" > [binNumber = 5] [binNumber = 1] | > > | > > ----------------------- > | > | > osg::Drawable > E0 osg::Drawable E1 > dft, so binNumber = > 0 [binNumber = 6] > > Is it B/E0 - D - C - A - E1 ? > > > Another example, closer to my current purpose test, practical to make multi > pass drawings : > > | > osg::Group > | > ------------------------------------------ > | | > | > | osg::Group "B" osg::Group "C" > | [binNumber = 20] [binNumber = 30] > | > osg::Geode "A" > [binNumber = 15] > > > Is it A - B - C ? > > > I think exploring a concrete example like that clear things. Thanks > > > > ----- Original Message ----- > From: "Tim Moore" <[EMAIL PROTECTED]> > To: "OpenSceneGraph Users" <[email protected]> > Sent: Thursday, October 04, 2007 2:00 PM > Subject: Re: [osg-users] RenderingHint vs binNumber(RenderBinDetails) > > > Robert didn't answer your second question; I'll have a go because I think > > I understand > > it. > > > > First of all, there aren't a fixed number of render bins. You can assign a > > StateSet > > to any integer, positive or negative. This turns out to be quite useful. > > > > When you say "set a rendering order on a group node," you mean that you've > > set the > > render bin in a state set in that node. There is an inheritance effect, > > but it may > > not be what you expect. Render bins can contain other render bins! If the > > children of > > your group node have state sets that also set the render bin detail, their > > render bins > > are stored inside the group state set's render bin, and they will be > > rendered in order > > when that render bin is traversed. > > > > This can give you unexpected results, when for example you assign a state > > sets with > > TRANSPARENT_BIN or OPAQUE_BIN to nodes up and down the scene graph :) On > > the other > > hand you can get very precise control of the ordering of drawables with > > it. In > > FlightGear I just used this feature to order cloud layers. The layers are > > too big for > > normal transparency sorting to work well, and you want to draw the cloud > > layer tops > > from low altitude to high and the bottoms from high to low. I used the > > altitudes > > of the layers as render bin numbers to get the right order: > > > > // Force the cloud layers into recursive bins of bin 4. > > osg::StateSet *rootSet = layer_root->getOrCreateStateSet(); > > rootSet->setRenderBinDetails(4, "RenderBin"); > > > > Child 0 has the bottom layers and child 1 has the tops: > > > > > > layer_root->getChild(0)->getStateSet()->setRenderBinDetails(-(int)layer_asl, > > > > "RenderBin"); > > > > layer_root->getChild(1)->getStateSet()->setRenderBinDetails((int)layer_asl, > > > > "RenderBin"); > > > > I hope someone will correct me if I've gotten this all wrong! > > Tim > > > > _______________________________________________ > 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
