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On Fri, 21 Feb 1997, Rikk Carey wrote: > Michael Paulitsch wrote: > > > > Hi Hirohisa, > > Hi Uma, > > > > Sorry for the confusion. If you try this piece of code you > > will realize that the Sphere will not move along the rotated > > coordinate system because the coordinates created by the > > PlaneSensor have a fixed Z value. > > > > [example deleted...] > > > > I want to go around an object rotate the planeSensor of that object > > according to the position of the avatar and I want to be able to > > move the object like if I had PlaneSensor perpendicular to the line > > of sight. > > > > The problem: I can't use a SphereSensor because this is not implemented > > What the heck does this have to do with a SphereSensor? Sorry, I mixed something up! Of course it has nothing to do with a SphereSensor! > > I would try combining a PlaneSensor with Billboard (if you want it > to face the viewer all the time). I would first rotate the sensor > from the XZ plane to the XY plane (so that it stands up). > I haven't tried this out or thought about it much, but am > confident that you can do what you want (if I understand > what you want). That's exactly what I have done but this doesn't alter the fact that one has to write a script with matrix calculation just because he wants his PlaneSensor to be a little bit rotated! > > > > So I thought that I can use a PlaneSensor and rotate according to > > the avatars position (which I get from a ProximitySensor) and will > > still get the same effect. > > Nope! > > This should work too (but Billboard might be less work). > Why "nope"? Because I made a mistake in programming it ;-) Sorry for the nope I have located my mistake now. It's a kind of event misordering thing that I didn't think of and has principally nothing to do with a PlaneSenser. > > > > My intention of that mail is to make clear that nobody can use a > > PlaneSensor if he rotates it. > > Not true. In my first posting I made clear that one could use a Script node to "adjust" the coordinates. In my opinion, nobody should have to use a Script node just because he wants to have his PlaneSensor rotated > > > > Imagine you build a big box, you are inside the box and you want to > > move objects only on the "walls". If you use a SphereSensor > > you always get a "PlaneSensor" perpendicular to your line of sight. > > Forget the SphereSensor... (for now)... OK!!! ;-) > > > > If you use a PlaneSensor it works fine for the wall in the XY planes > > but not for any other planes! > > This is wrong. First, you need to understand that PlaneSensors > are designed to work in their LOCAL XY coordinate system (not > the global coord sys). Thus, you an apply a Transform node to > rotate the PlaneSensor into the whatever orientation you wish. > However, you must be careful about how to apply the results. I recognized that fact!! But as I said, one shouldn't have to write a script to do so. If you have another simpler solution then please tell it to us! > > If I was not busy on the spec, I would provide an example. > Maybe later... Would be very nice! > > > > My personal opinion is that the guys who wrote the specification did > > think of that but didn't have a solution because of the > > fact that you can have 2D and 3D devices. > > Not true. It was my opinion, sorry! > > > > My objective is to start a discussion about the usefulness of a > > rotation field (similar to the offset field) in a PlaneSensor. > > You can get the results you want (sorry that I don't have the time > right now to provide an example)... Please, would be nice. But *without* a Script node. I know how to do it with a script node. Once again, the reason why I wrote this mail is to point this fact out and maybe you can think about it when you write the spec. It's no big deal to add a rotation field and it would make things easier. As I said, it's my personal opinion and you don't have to agree but I feel better now because I know that somebody who wrote/writes the spec knows it now. I tried/try to give some feedback!! Hope you appreciate that and that you don't see it as a critic on the spec. You did a great Job, thanks! PS: I'm eagerly waiting for the next IRIX beta version! > > > > > On Fri, 21 Feb 1997, Rikk Carey wrote: > > > > > Nope. The offset field has nothing to do with positioning (or > > > orienting) the sensor. Rather, if autoOffset is TRUE the offset > > > field is added to the results of the sensor's output > > > (e.g., translation_changed for PlaneSensor, rotation_changed > > > for SphereSensor). > > > > > > This feature provides the ability to give you persistent sensors. > > > This means that they will accumulate their results each time you > > > twiddle it, rather than reseting back to their original state. > > > > > > This is subtle. I recommend that you experiment with it by setting > > > autoOffset to FALSE (do a test) and then set autoOffset to TRUE > > > (do a test). In simple cases, you will typically ignore the value > > > of the offset field itself (the sensor uses it internally). > > > -- > Rikk Carey rikk@best.com > 415-969-5910 VRML 2.0: http://vrml.sgi.com/moving-worlds/ > --- Michael PAULITSCH ---------- http://www.crhc.uiuc.edu/~michael/ --- ------------------------------------------------------------------- *** Please send administrative requests to <majordomo@sdsc.edu> *** -------------------------------------------------------------------
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