Thanks for sharing the VEX snippet :) I've totally missed out on that "point" function.
I'll check Sticky as well. have a nice evening ! 2015-02-02 17:33 GMT+01:00 Jordi Bares Dominguez <[email protected]>: > 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]> 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]>: >> >>> And the Rivet SOP too >>> >>> > On 2 Feb 2015, at 12:55, [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]> 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> >>> >>> >>> >>> 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]> >: >>> >>>>>> 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/> > > >
