ARGHHH, I keep sending stuff before I edit it this week. "The local kinematics of an object is nothing but a transform multiplied by its parent's transform." Should read: "The local kinematics of an object is nothing but a transform that will be multiplied by its parent's transform to create the object's global."
On Wed, Aug 14, 2013 at 10:40 AM, Raffaele Fragapane < [email protected]> wrote: > The local kinematics of an object is nothing but a transform multiplied by > its parent's transform. > So if you have a transform, and want it to be an object's local transform > instead of its global, you take that transform, and multiply it by the > parent's. > > IE: You want something to be offset from its parent by 1.0 in the Y all > you need is > vector(0.0, 1.0, 0.0) --> (pos)SRT 2 4x4 Matrix --> multiply <-- parent > transform matrix > > What I'm saying is that you DO NOT need write access to the local kine of > an object, writing to its global is perfectly fine, all you need to do is > take into account its parent's transform and you can emulate local > perfectly fine. > > The only "limitation" is that an ICE graph can't traverse the scene, so > you can't have something in the graph saying "parent matrix" and that will > be scene aware, you always need to explicitly pull in the object that is > its parent to "configure" your graph so it's aligned to the scene. That > part you need to script, but it's trivial to do so. > > No need to drop ICE for scripts, other than for that connection, if your > only concern is the lack of write access to local, it's unnecessary anyway. > > > On Wed, Aug 14, 2013 at 10:23 AM, Nicolas Esposito <[email protected]>wrote: > >> Ciao Raffaele, >> >> >> The main point is that with ICE I succesfully managed to constraint two >> nulls together ( one with the animation, the other one basically follow the >> animated null ), but once I set the kine.global position I can see that it >> will "jump" to the animated null position as expected, but I don't know how >> to do: >> - change the "follow null" position, means that I want this null to be in >> its original position, not to be in the exact same spot as the animated null >> - as for "kine.local multiplied by a custom parameter value" I can >> modulate the animation of a driven null as described above ( ModelB is >> linked to the nulls.... ), so I'm not able to set the "follow null" >> original position and then be able to insert a "Multiply by scalar" to >> modulate its max/min the animation as set using kine.local*custom parameter >> >> I was thinking ( and tried ): >> - I used a third static null that will be in the exact same sport as the >> "follow null", use Get distance between and set the kine.global >> properly...but once I set the kine.global how can I add a multiplier for X, >> Y and Z axes in order to modulate those values as I'm doing using the >> kine.local by expressions? >> - Probably there is smething that I'm doing wrong, but in the end of the >> ICE tree I always need to set the kine.global of my "follow null", so if in >> the tree below I try to set for example the X, Y and Z value ny multiply >> everything by a scalar I override the kine.global that I set before... >> - Used StaticKine, nothing has really changed >> - Set self.TMP values to store the original position by using a third >> null, it works, but I always end up of having the same problem of setting >> the kine.global, but then I'm not able to modulate the animation as >> described by kine.local >> >> I'm willing to use kine.global, but seriously if I can't modulate those >> values ( and keep the "follow null" in its original position ) I'm still >> going to use the expressions with custom parameters... >> >> I'm learning a lot recently about ICE, but right now I can't think about >> a solution that allows me do what I just described....its driving me mad :D >> >> Cheers >> >> Nicolas >> > > > > -- > Our users will know fear and cower before our software! Ship it! Ship it > and let them flee like the dogs they are! > -- Our users will know fear and cower before our software! Ship it! Ship it and let them flee like the dogs they are!
