Oh well, there's always "cheesy transparency" -- order-independent transparency using polygon stipple... :-/ -Paul
> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > Gordon Tomlinson > Sent: Thursday, April 19, 2007 9:32 AM > To: 'osg users' > Subject: RE: [osg-users] translucent objects disappear > > Even BSP's don't solve all the problems and they are still > pretty much view dependent ;( in any complex scene > > And you modelers will curse you to the end of time modeling > to BSP, lets say a pain :( > > Until we can afford to sort at the poly level this will not > go away ( even then its not just a sort issue), > > We need the 'Binford Power MKIII Sorter" ... More power ...... > > __________________________________________________________ > Gordon Tomlinson > > Email : [EMAIL PROTECTED] > Website : www.vis-sim.com www.gordontomlinson.com > > __________________________________________________________ > > "Self defence is not a function of learning tricks but is a > function of how quickly and intensely one can arouse one's > instinct for survival" > -Master Tambo Tetsura > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > Thrall, Bryan > Sent: 19 April 2007 16:14 > To: osg users > Subject: RE: [osg-users] translucent objects disappear > > Paul Martz wrote on Thursday, April 19, 2007 9:58 AM: > > Good analysis. > > > > It occurs to me that there might be room for an enhancement to the > > back-to-front sorting in the transparent bin such that it > sorts based > > on minimum distance rather than bounding volume center. > > -Paul > > That would be an improvement in some cases, but not in others > (for example, a very large polygon with one nearby vertex and > a smaller polygon farther than that vertex but nearer than > all the other vertices of the large polygon). Unfortunately, > pretty much whatever generic sorting strategy you use will > have issues. > > What we really need is a BSP for the transparent stuff; that > would ensure that they are always rendered in the right > order. But that would require (1) a Nodekit for BSPs and (2) > scenegraphs properly built with the BSPs. I'd love to do (1), > but I have no time :( > > >> -----Original Message----- > >> From: [EMAIL PROTECTED] > >> [mailto:[EMAIL PROTECTED] On Behalf Of > Paul Speed > >> Sent: Wednesday, April 18, 2007 9:32 PM > >> To: osg users > >> Subject: Re: [osg-users] translucent objects disappear > >> > >> (Two Pauls double-teaming...) > >> > >> I believe this comes down to the brute force way that OSG sorts > >> drawables in the transparent bin. This is not always > sufficient to > >> ensure proper rendering order... and there's really not > much OSG can > >> do about either. At least not and still render in real time. > >> > >> If all of one type of object is inside of another and is > frequently > >> obscured by the outer object then you can use the bin numbers > >> (setRenderBinDetails if my memory is good) to make sure the inside > >> objects are always drawn before the outer. The problem you see > >> happens because the outer object is drawn first and fills the > >> Z-Buffer... when the interior objects go to draw they are obscured > >> since the z-buffer doesn't know about that. > >> > >> Hopefully that isn't review. I think everyone on this > list has hit > >> this one time or another and the work-arounds always depend on the > >> situation. > >> Sometimes controlling rendering order with the relative > bin numbers > >> is a work-around. > >> > >> -Paul > > -- > Bryan Thrall > FlightSafety International > [EMAIL PROTECTED] > _______________________________________________ > osg-users mailing list > [email protected] > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ > > > _______________________________________________ > osg-users mailing list > [email protected] > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
