I haven't used Houdini in this context, but I do know a little math. The point reference frame in Softimage not much more than an orthogonal basis comprised of the U tangent, V tangent, and surface Normal (for surfaces). For polygon meshes it follows some rules such as the winding of the polygon to determine the first edge which becomes a pseudo X axis. That crossed with the normal produces the Z axis. The combination of the three produces the matrix which represents the frame.
In other words, if you know the rules of the geometry construction, creating the reference frame shouldn't be more than a few cross products and normalizing. Actually, you don't need to know the rules, you just need 'a' rule which is consistently followed. Matt Date: Tue, 28 Mar 2017 10:04:47 +0100 From: <p...@bustykelp.com> Subject: Re: Random Thoughts about H. To: "Official Softimage Users Mailing They fixed it quicker than it took me to make a video showing how annoying it could be! I have a question regarding attributes.. In ICE. I use ?pointreferenceframe? all the time for finding the orientation at a surface for making deformers. In Houdini, there are not all these useful attributes that ICE has by default. I can make a thing that calculates a homemade orientation a-la PointReferenceFrame, and it works but it takes up a huge amount of nodes. Also, you can?t just ?get? it. It needs loads of inputs on the tree that?s finding it. Firstly. I don?t see that you can store a matrix per-point attribute. Is it possible? How would an experienced Houdini person deal with getting/calculating Pointreferenceframe on a surface? ------ Softimage Mailing List. To unsubscribe, send a mail to softimage-requ...@listproc.autodesk.com with "unsubscribe" in the subject, and reply to confirm.
