[osg-users] PSSM: Latest Version : Please Test and Debug

Robert Osfield robert.osfield at gmail.com
Fri Sep 21 06:04:39 PDT 2007


Hi Adrian,

I understand the technique enough to comment I'm afraid.

Robert.

On 9/21/07, Adrian Egli <3dhelp at gmail.com> wrote:
> Hi Roberts
>
> i am working on the texture selection in GLSL, but unfortunately the
> gl_FragCoord.z is not for all situation between 0 .. 1. I n some cases,
> if a triangles, has a visible part in the [near,far] range and a hidden part
> behind the current viewing camera near, the value is from x..1, with x > 0.
> Why is the value not
> from near .. far allways 0..1, is this an know ATI bug or do i something
> missunderstand. Or should i add a special matrix? or how can i fix this
> issue in fragment shader.
>
> /adegli
>
>
>  2007/9/19, Adrian Egli <3dhelp at gmail.com>:
> > Thanks robert,
> >
> > i will working on NVidea System (Friday) and i hope that i can fix the
> problems.
> > The z fighting is a know problem, but i don't yet know wether it come with
> ati / nvidea.
> >
> > i will fix it friday.
> >
> > regards adrian
> >
> >
> > 2007/9/19, Robert Osfield <robert.osfield at gmail.com >:
> >
> > > Hi Adrian,
> > >
> > > To help things along I have gone ahead and merged your ShadowPSSM
> > > implementation, but renamed it to ParallelSplitShadowMap to be in
> > > keeping with the naming of the other shadow techniques.
> > >
> > > I have also added the PSSM enabling into osgshadow.cpp, but haven't
> > > merged PSSM.cpp as I didn't know what to do with this.
> > >
> > > When enabling --pssm in osgshadow I get shadows, but also z fighting
> > > artificats that suggest the polygon offset needs to be adjusted a bit.
> > > Bascially glPolygonOffset is not a standardised quantity under OpenGL
> > > so implementations vary, if you optimize for ATI it'll not work well
> > > under NVidia and visa versa.  We've seen this issue with osgText
> > > before and made some tweaks to try and cope with the variance.  See
> > > src/osg/PolgyonOffset.cpp.  It could be that the code in there that
> > > tries to account for ATI might not be work well with recent drivers.
> > >
> > > Robert.
> > >
> > > On 9/19/07, Adrian Egli <3dhelp at gmail.com> wrote:
> > > > Sorry Robert,
> > > >
> > > > i still fixed an issue this morning, and added also for debugging a
> define
> > > > for enable r,g,b for 3 split maps, to color them (DEBUG)
> > > >
> > > > regards adrian
> > > >
> > > > 2007/9/19, Adrian Egli < 3dhelp at gmail.com>:
> > > > > Hi Robert,
> > > > >
> > > > > i did some changes in latest implementation, i now i have a PSSM
> variant
> > > > which works quite well. I propose to check this implementation into
> > > > osgShadow. Of course this is just the first version of our PSSM
> > > > implementation, but we are still open to change the implementation is
> > > > implemented it as a shadow technique as you mentioned. A future
> > > > implementation can be the one Terry started some month ago, but i
> don't know
> > > > when he will be able to post a adapted version to our shadow technique
> > > > abstraction.
> > > > >
> > > > > in the attachment we have to VS2003 project:
> > > > > * First my test case, may we can add this as new example.
> > > > > * Second is the osgShadow example from the SVN with changes i did,
> marked
> > > > with //ADEGLI
> > > > > -> the source
> > > > > -> test.bat, you can see what i tested, the test.ive is a database
> > > > downloaded from
> > > >
> http://www.vision.ee.ethz.ch/~pmueller/wiki/CityEngine/DownloadModelsPompeii
> > > > >
> > > > > others should test. some problem can cause the PolygonOffset, i
> tested it
> > > > on two different system with different GPUs, all under windows, i ll
> test as
> > > > soon as i have some minutes left also under os/x
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > /regards
> > > > >
> > > > > adegli
> > > > >
> > > > >
> > > > > 2007/9/18, Robert Osfield <robert.osfield at gmail.com >:
> > > > >
> > > > > > Hi Adrian and Terry,
> > > > > >
> > > > > > New shadow algorithms need to be implemented as a subclass from
> > > > > > osgShadow::ShadowTechnique for them to be considered for merging
> with
> > > > > > SVN. All the hooks required to implement advanced techniques are
> > > > > > available to the shadow techniques so it shouldn't cause any
> > > > > > significant problems in implementing the PSSM as a
> ShadowTechniqiue.
> > > > > >
> > > > > > The use of ShadowTechnique is important as it allows end users to
> > > > > > trial out different techniques very easily and find the route
> which
> > > > > > best suits their hardware and scene type.  It is even possible
> that
> > > > > > different techniques will be used by one application as they load
> up
> > > > > > different scenes.
> > > > > >
> > > > > > I did review Terry's PSSM code and did consider porting it across
> to
> > > > > > work as a ShadowTechnique, but alas I've just been snowed under be
> > > > > > other work.  The same is the case right now, while I'd love to see
> a
> > > > > > good PSSM implementation checked into osgShadow I don't have the
> time
> > > > > > to help out in this effort.
> > > > > >
> > > > > > Robert.
> > > > > >
> > > > > >
> > > > > > On 9/18/07, Adrian Egli < 3dhelp at gmail.com> wrote:
> > > > > > > Hi Terry,
> > > > > > >
> > > > > > > i don't know what robert requires of PSSM. The best and easiest
> would
> > > > be to
> > > > > > > integrate it as a shadow technique, so the user can just change
> the
> > > > shadow
> > > > > > > technique
> > > > > > > and that's it. Or ?
> > > > > > >
> > > > > > > adegli
> > > > > > >
> > > > > > > 2007/9/17, Terry Welsh < mogumbo at gmail.com>:
> > > > > > > > Do you know what Robert requires of PSSM to have it included
> in OSG?
> > > > > > > > Does it just need to be integrated with osgShadow?
> > > > > > > > --
> > > > > > > > Terry Welsh - mogumbo 'at' gmail.com
> > > > > > > > www.reallyslick.com   |  www.mogumbo.com
> > > > > > > >
> > > > > > > > On 9/17/07, Terry Welsh < mogumbo at gmail.com> wrote:
> > > > > > > > > Well, I took a closer look.  There are a few problems, but I
> still
> > > > > > > > > can't bring myself to try and fix them since they're
> problems I
> > > > > > > > > already fixed in my own shadow code.  It would really be
> easier
> > > > and
> > > > > > > > > faster to work from that code instead I think.  How badly do
> you
> > > > want
> > > > > > > > > to get this working?  I can always send you the current
> version of
> > > > the
> > > > > > > > > shadow code I have here.
> > > > > > > > >
> > > > > > > > > To be more specific, it looks like the big problems are 1.
> Shadow
> > > > maps
> > > > > > > > > don't always cover all of the terrain (they leave some parts
> > > > > > > > > unshadowed) (this seems to depend on scene size), and 2.
> > > > Off-camera
> > > > > > > > > objects don't always cast shadows.  There are some other
> minor
> > > > > > > > > problems, but those are the big ones.
> > > > > > > > > - Terry
> > > > > > > > >
> > > > > > > > > On 9/17/07, Adrian Egli <3dhelp at gmail.com> wrote:
> > > > > > > > > > hi Terry,
> > > > > > > > > >
> > > > > > > > > > i hope you can test the latest version of PSSM. it would
> be
> > > > greate as
> > > > > > > soon
> > > > > > > > > > as possible to integrate it
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > * GLSL Shader: generate automatically for 1..n splitting
> maps
> > > > > > > > > > * some changes for better frustum splitting
> > > > > > > > > >
> > > > > > > > > > *** PLEASE test it on your databases ****
> > > > > > > > > >
> > > > > > > > > > attached some tests screenshots. if you have some bugs,
> please
> > > > (A)
> > > > > > > report it
> > > > > > > > > > or (B) fix it and send me the updated source code.
> > > > > > > > > >
> > > > > > > > > > Tested on ATI X1600, 256MB, mobile macbookpro
> > > > > > > > > >
> > > > > > > > > > thanks for testing
> > > > > > > > > >
> > > > > > > > > > adrian
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > 2007/9/15, Adrian Egli < 3dhelp at gmail.com>:
> > > > > > > >
> > > > > > > > > > > Hi latest version,
> > > > > > > > > > >
> > > > > > > > > > > (1) NVidea Cards, the setting of the Polygon offset
> seems to
> > > > be not
> > > > > > > > > > correct on my ATI it's seems to be correct (looks nice)
> > > > > > > > > > >      please test and check for good values, i don't now
> a good
> > > > value
> > > > > > > for
> > > > > > > > > > this
> > > > > > > > > > > (2) GLSL shader has to be generated dynamic, if we
> change the
> > > > number
> > > > > > > of
> > > > > > > > > > split planes
> > > > > > > > > > >      the version no longer need any IF in the GLSL
> shader,
> > > > this
> > > > > > > makes the
> > > > > > > > > > good a little bit different form the suggestion in the
> paper
> > > > PSSM
> > > > > > > > > > > (3) try it out and test
> > > > > > > > > > >
> > > > > > > > > > > pssm --help
> > > > > > > > > > >
> > > > > > > > > > > enjoy and have a nice weekend, i will be not online till
> > > > monday. if
> > > > > > > you
> > > > > > > > > > have some ideas, fixes etc please send me the new code.
> then i
> > > > will be
> > > > > > > able
> > > > > > > > > > to test it
> > > > > > > > > > > out. i hope for next osg release we will have a good and
> > > > robust PSSM
> > > > > > > > > > implementation what would be greate.
> > > > > > > > > > >
> > > > > > > > > > > the next version of PSSM would have project maps, at the
> > > > moment it
> > > > > > > > > > supports just directional lights
> > > > > > > > > > >
> > > > > > > > > > > /adegli
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > > 2007/9/14, Adrian Egli < 3dhelp at gmail.com>:
> > > > > > > > > > >
> > > > > > > > > > > > hi,
> > > > > > > > > > > >
> > > > > > > > > > > > i will post the first version of the PSSM for a sun as
> > > > directional
> > > > > > > > > > lights.
> > > > > > > > > > > >
> > > > > > > > > > > > Please help in test, debug, and optimisation, than we
> can
> > > > > > > integrate it
> > > > > > > > > > into OSG core, i would like doing this as soon as
> possible.
> > > > > > > > > > > >
> > > > > > > > > > > > call in a console...
> > > > > > > > > > > > PSSM --help
> > > > > > > > > > > >
> > > > > > > > > > > > example
> > > > > > > > > > > > PSSM.exe   dumptruck.osg  --noUpdate --mapcount 3
> > > > > > > > > > > > PSSM.exe  dumptruck.osg  --noUpdate --mapcount 3
> --NO-DEBUG
> > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > > * we need a better GLSL shader ! My version isn't yet
> good
> > > > enough
> > > > > > > (and
> > > > > > > > > > robust)
> > > > > > > > > > > >
> > > > > > > > > > > > * i guess there is still a little bug, the near-far
> clipping
> > > > plane
> > > > > > > for
> > > > > > > > > > the each camera (shadow)
> > > > > > > > > > > >
> > > > > > > > > > > > * ...
> > > > > > > > > > > >
> > > > > > > > > > > > others
> > > > > > > > > > > >
> > > > > > > > > > > > thanks for help
> > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > > / adrian
> > > > > > > > > > > >
> > > > > > > > > > > > --
> > > > > > > > > > > >
> > > > ********************************************
> > > > > > > > > > > > Adrian Egli
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > > --
> > > > > > > > > > >
> ********************************************
> > > > > > > > > > > Adrian Egli
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > --
> > > > > > > > > >
> ********************************************
> > > > > > > > > > Adrian Egli
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > --
> > > > > > > > > >
> ********************************************
> > > > > > > > > > Adrian Egli
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > --
> > > > > > > ********************************************
> > > > > > > Adrian Egli
> > > > > > > _______________________________________________
> > > > > > > osg-users mailing list
> > > > > > > osg-users at lists.openscenegraph.org
> > > > > > >
> > > >
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
> > > > > > >
> > > > > > >
> > > > > > _______________________________________________
> > > > > > osg-users mailing list
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> > > > > >
> > > >
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > ********************************************
> > > > > Adrian Egli
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > ********************************************
> > > > Adrian Egli
> > > > _______________________________________________
> > > > osg-users mailing list
> > > > osg-users at lists.openscenegraph.org
> > > >
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
> > > >
> > > >
> > > >
> > > _______________________________________________
> > > osg-users mailing list
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> > >
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
> > >
> >
> >
> >
> > --
> > ********************************************
> > Adrian Egli
>
>
>
> --
> ********************************************
> Adrian Egli
> _______________________________________________
> osg-users mailing list
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