On Wed, 2008-10-01 at 10:57 -0400, Tomlinson, Gordon wrote: > Why should there be an example of this ? >
It's such a fundamental aspect of a scenegraph. From all the example's I've seen in osg, everything is put on the root level. There's no concept of a local coordinate system based on some (root) object. Using opengl, I simply push the global coordinate system on the stack, rotate and translate each item and then ultimately pop the stack to get back to my global coordinate system. I was simply interested in how osg and OpenGL compared. > You're the 1st person to this ask for particular exact usage, that I > have seen on this list. > > As to examples of using just transforms there are many and they are also > covered in most of the tutorials online and into the Guide to OSG > written by Paul Martz > I shall hunt these down. > You might want to Google around on scene graphs and > transformations/matrices and how they can be used, to provide local > coordinate systems, how you can chain for certain actions( there are > some things you cannot do by simply using child transforms you have to > do the math in many cases) , there's a lot on the net, also look at how > vis-modeling packages like MultigenCreator, Carbon Grpahics Geo, Remo3D > etc provide tools to create the models and transformation chains > Thanks for these pointers. I'm trying to see if osg can be used in my project. > > Gordon > > __________________________________________________________ > Gordon Tomlinson > Product Manager 3D > Email : gtomlinson @ overwatch.textron.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 James > Moliere > Sent: Wednesday, October 01, 2008 10:10 AM > To: OpenSceneGraph Users > Subject: Re: [osg-users] connected shapes demo... > > J.P. > Thanks for the advice. I believe I see how to connect objects together > and will hand over a sample if I can get one going. I'm sorta in > disbelief that an example like this doesn't seem to exist. > > James > > J.P. Delport wrote: > > hello, > > > > you can connect transforms together in a parent child fashion, this is > > > what a scene "graph" is for. > > > > Try make yourself an example with the following structure: > > > > root > > | > > transform1 -- shape1 > > | > > transform2 -- shape2 > > | > > transform3 -- shape3 > > > > transform1 is child of root > > shape1 and transform2 are children of transform1 ... > > > > jp > > > > > > James Moliere wrote: > >> Gordon, > >> Thanks for letting me know this. > >> > >> Is there a concept of parent/child relationships in OSG with respect > >> to primitive objects? ...To make the cylinder example work? Are all > > >> objects that are placed into the scene work off of global > coordinates? > >> James > >> > >> Gordon Tomlinson wrote: > >>> Nope there's no example that shows this, but many things are > >>> possible with by writing code > >>> > >>> __________________________________________________________ > >>> Gordon Tomlinson > >>> [EMAIL PROTECTED] > >>> IM: [EMAIL PROTECTED] > >>> www.vis-sim.com www.gordontomlinson.com > >>> __________________________________________________________ > >>> > >>> -----Original Message----- > >>> From: [EMAIL PROTECTED] > >>> [mailto:[EMAIL PROTECTED] On Behalf Of > >>> James Moliere > >>> Sent: Tuesday, September 30, 2008 10:36 PM > >>> To: [email protected] > >>> Subject: [osg-users] connected shapes demo... > >>> > >>> Hello, > >>> Is there a connect shapes example? For instance, I'd like to have 3 > > >>> cylinders where 2 of the cylinders connected sequentially at the end > > >>> of the previous cylinder. When I rotate cylinder 1, I'd like the > >>> others to rotate about cylinder 1 as though they are connected > >>> without doing any extra calculations. The same goes for cylinder 2 > >>> but this time cylinder 1 stays stationary and cylinder 3 moves. Is > >>> this possible? Is there an example that shows this? > >>> > >>> Thanks! > >>> > >>> _______________________________________________ > >>> osg-users mailing list > >>> [email protected] > >>> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegrap > >>> h.org > >>> > >>> > >>> _______________________________________________ > >>> osg-users mailing list > >>> [email protected] > >>> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegrap > >>> h.org > >>> > >>> > >>> > >> > >> _______________________________________________ > >> 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.or > g > _______________________________________________ > 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
