Have a look at Sticky SOP, may be the thing you are looking after (plus you have blending via UVs which is very interesting.
jb > On 2 Feb 2015, at 15:58, Christopher Crouzet <[email protected]> > wrote: > > Disclaimer: I'm a total beginner and there's most likely better/easier ways > to do it. > > If you want to constrain your object to a single point, one way would be to > create an expression on each of the translate channels of your object and use > the `point` function, such as: `point("/obj/path_to_geometry", point_number, > "P", index)` where `index` is 0 for the position X, 1 for the position Y and > 2 for the position Z. > > If you want your object to snap to an actual group of points, then the idea > that I've got is slightly more involved. > Basically, you'd need to put your points into a group and create an > `AttribWrangle` in which you'd loop over the points in the group and return > an average position. > Here's a working VEX snippet: > > vector @clusterPosition = {0, 0, 0}; > > int count = 0; > int ptnum; > vector P; > int handle = pcopen(@OpInput1, "P", {0, 0, 0}, 1e6, int(1e6)); > while (pciterate(handle)) { > pcimport(handle, "P", P); > pcimport(handle, "point.number", ptnum); > if (inpointgroup(@OpInput1, "group_name", ptnum)) { > @clusterPosition += P; > count++; > } > } > > if (count > 0) { > @clusterPosition /= count; > } > > Note that the `pcopen` function creates a point cloud with a K-D tree, so > it's really overkilled here. I'll be looking forward a better answer to that > one! :) > > Also both solution will match only the position. To also match the > orientation, you might want to use the attributes created by `PolyFrame`. > > > On 2 February 2015 at 22:01, philipp seis <[email protected] > <mailto:[email protected]>> wrote: > hey guys, i'd be super happy for any advice on an "object to cluster > Constraint" in H, > like i would use it for a dorrito > > 2015-02-02 15:38 GMT+01:00 Jordi Bares Dominguez <[email protected] > <mailto:[email protected]>>: > And the Rivet SOP too > > > On 2 Feb 2015, at 12:55, [email protected] > > <mailto:[email protected]> wrote: > > > > You might want to check out the Creep SOP in that case. > > > > > > A > > > > > > On 02 February 2015 at 12:27 Gerbrand Nel <[email protected] > > <mailto:[email protected]>> wrote: > > > > > >> Thanks guys!! > >> What I want out of a surface deformer is the UV control. > >> It's different than a cage or lattice because it lets you slide/deform > >> things > >> based on uv data, and offset along normals > >> I find it very useful to model things where allot of detail has to follow a > >> certain shape. > >> I modelled some running shoes in the beginning of the year, and all of the > >> parts followed this one master nurbs surface. > >> I'll look into the ray sop and lattice, but I think a surface deformer > >> digital asset might need to be made :) > >> One that works like soft. > >> This way I can "engine" it into bloody maya if I ever need to go to that > >> dark > >> place again. > >> G > >> > >> On 02/02/2015 12:45, philipp seis wrote: > >> > >>>> Hi Gerbrand, > >>> > >>> from the top of my head i'd say, there should be a checkbox so that > >>> your curve > >>> won't get a surface. > >>> Then, here is a curve basics tutorial from peter quint: > >>> http://vimeo.com/40771484 <http://vimeo.com/40771484> > >>> <http://vimeo.com/40771484 <http://vimeo.com/40771484>> > >>> > >>> I'd be interested in a deform by surface too. The Ray SOP gives a > >>> little bit of that > >>> behaviour out of the box, and the attribute transfer SOP as well, if > >>> "match Point Position" ( i guess that was the name) Checkbox is on. Those > >>> 2 > >>> work on proximity. > >>> And finally you might want to try the Lattice SOP, which in Houdini is > >>> also customizable, > >>> ending up being very close to the cage deformer from Soft. > >>> And then, you could also add a "Normal attribute" to your SOP, with > >>> the > >>> point SOP, and create a VOPSOP in which you manipulate those. This might > >>> be > >>> the equivalent to an ICE "closest point to location" node. > >>> I'd consider myself a real houdini novice though, just trying to > >>> transfer my Softimage workflows, so please correct me if i'm wrong. > >>> > >>> I would like to add the question: How would you do a simple "Object to > >>> Cluster Constraint ?" > >>> So far i found only options that are uv based, like the "rivet"... > >>> > >>> best, Philipp > >>> > >>> > >>> > >>> > >>> > >>> > >>> 2015-02-02 10:43 GMT+01:00 Gerbrand Nel <[email protected] > >>> <mailto:[email protected]> > >>> <mailto:[email protected] <mailto:[email protected]>> >: > >>>>>> So 3 quick houdini questions if you don't mind: > >>>> Why do I automatically get a surface on a closed curve? > >>>> Can I kill it without killing the curve, or can I set it to "never > >>>> create"? > >>>> Is there something like "deform by surface" in soft for houdini? > >>>> That is it for now :) > >>>> Thanks > >>>> G > >>>>>> > >>> > >>>> > > > > > > > -- > Christopher Crouzet > http://christophercrouzet.com <http://christophercrouzet.com/> >
