i haven't looked at the library yet - but i'm guessing Integrate() is going to acutally move your objects. it'll perform an integration step on the objects - looking the forces that are acting on each object and resolving them. to do this it needs to know how much 'time' to use - if you're talking about applying a force to an object you have to apply that force for a particular length of time in order to actually move it - and the more time you apply the force for the more you'll move the object (in general). so you have to pass an argument telling it how much time to use in its calculations.
dt is an abbreviation of 'delta t' - delta meaning change and t being a popular reduction for 'time' a smaller dt value will result (usually) in a more accurate simulation at the expense of performance. But physics simulations can be a bit of a 'black art' and can take some time to get balance just right. there are tons of examples and tutorials around the net - but it can take a bit of time to work through them to understand things fully. T On Thu, Feb 5, 2009 at 12:37 AM, JBob <[email protected]> wrote: > > Thanks, found out about singletons & getInstance(), but still > wondering how exactly to use Integrate(). I've searched for > discussions on jiglib vs. wow and have always read jiglib is much more > powerful, so that's why I'm trying to use it instead of wow. I figure > the project will mature quickly anyhow, seeing what they've already > done. > > On Feb 3, 8:51 pm, katopz <[email protected]> wrote: > > far as i can tell is, the engine is fast but didn't seem to be perfect > yet, > > some weird behavior still remain > > also transform didn't apply to physics system while init time > > my suggestion is you better wait for huge change/fix for their engine in > a > > few day (maybe ;D) > > and also more support for away3d engine and others (they said) > > for now, all you see in my blog it's all i know by now really ;) > > > > btw, i'll waiting new one too, just don't need to rewrite all code again > ;) > > > > 2009/2/4 JBob <[email protected]> > > > > > > > > > > > > > Lol gotta love that. Well seeing this I might as well ask as I haven't > > > been able to find much on jiglib other than the couple samples. I've > > > got a plane with a JBox attached to it as the ground in a scene, and > > > an avatar among other static structures in the scene. The avatar has a > > > JSphere attached and the other structures JBoxes. > > > > > My first question is would it be possible to instantiate an object of > > > the PhysicsSystem class or do I have to use getInstance() (and why it > > > is used in the first place if you know). My other is about the > > > PhysicsSystem.Integrate(Number) method. What is the purpose of the dt > > > argument and how much does it manipulate the J-Primitives in the > > > current PhysicsSystem (though I just thought maybe dt = delta time?). > > > Please fill me in as much as you can/are willing, I'm not very > > > familiar with using physics libraries programmatically in general. The > > > idea is simply to move the avatar around while applying physics to it, > > > which right now is just collision detection, although with the code > > > I've written my avatar falls straight thru the ground on app launch. > > > I've checked to make sure that the avatar starts off a bit above the > > > ground and that the J-Primitives are as large as their respective > > > meshes. > > > > > On Feb 2, 8:45 pm, katopz <[email protected]> wrote: > > > > how can i say no ;) > > > > > > 2009/2/3 phreakquency <[email protected]> > > > > > > > Anybody have a look at this? > > > > > > >http://sleepydesign.blogspot.com/search/label/Away3D > > > > > > -- > > > > katopzhttp://www.sleepydesign.com > > > > -- > > katopzhttp://www.sleepydesign.com > -- Trevor Burton http://www.flashmonkey.org http://www.paperworld3d.com http://www.infrared5.com
