> On 2 Jan 2015, at 12:39, Stefan Kubicek <[email protected] > <mailto:[email protected]> > wrote: > > > PS: If the runners trails are meant as a graphical element rather than an > actual physical element in your picture I doubt I will look nice when it > collides with the runner. >
Agreed. I doubt it would give you a look that you want and probably isn’t worth spending too much time trying to make a robust system to make it work. Do a few quick tests first to see if it’s going to take you in the right direction. As a quick alternative, why not try setting the StrandColor to black for any strand points that fall inside your collision geometry, and then incorporate that as a multiply operation into your shader? That'll hide any parts of the strand that go inside your character. A On 02 January 2015 at 12:39 Stefan Kubicek <[email protected]> wrote: > Hi Olivier, > > I think there are example scenes for strand collision that ship with XSI. No > friction between strands and geo is modeled as far as I can remember, but it > might get you started. > > Then there is also the strand collision framework for more accurate > collisions, but I don't know how it reacts to changing point counts and strand > length: http://softimage.tv/strand-collision-framework/ > > PS: If the runners trails are meant as a graphical element rather than an > actual physical element in your picture I doubt I will look nice when it > collides with the runner. Maybe you could solve this in comp and get around > explaining collisions entirely? > Here is a nice example in a recent Glassworks spot that might be similar to > what you to try to achieve: > http://softimage.tv/lycra-moves-you/ > > Good luck, > > Stefan > > > > > > > Hello, long time reader, first time poster here! > > > > > > So I have a bit of a problem on my hands. > > > > > > We are doing a very simple concept, a sportsman whose back is leaving > > strand trails as he goes. This is child's play so far. > > My issue is that we would like the trails to interact with the mesh when, > > for various reasons, he cuts through them again. > > IE : at some point he falls to the ground and stands back up. The unwanted > > behaviour is that the strands generated from the back of his head will > > simply go through his head as he rises up, resulting in a somehow vertical > > strands column masking his face and fore-body. The desired behaviour is that > > the strands will flow around his cranium, maybe along his back, effectively > > leaving at least his face apparent. > > > > > > Animation is done in Maya and transfered over via geocache. > > > > I tried to operate with tools like 'closest location' or 'get location by > > raycast' applied to the strandpositions when inside the volume to simulate > > collision, but these were all lacking. The raycast solution may be > > promising, but I don't know how to set the correct direction vector. And > > sometimes the animation I'm working with may "skip" a strandposition, > > effectively not triggering the 'inside volume' condition. > > > > > > So yeah basically I don't know how to do that in a visually pleasing way. > > If anyone had some pointers, I'd be very grateful ! > > > > Thanks, > > Olivier > > > > > > > > > > > -- > > ----------------------------------------------------- > Stefan Kubicek <a href="mailto:"[email protected]"; > <[email protected]>">[email protected] > ----------------------------------------------------- > Alfred Feierfeilstraße 3 > A-2380 Perchtoldsdorf bei Wien > Phone: +43 (0) 699 12614231 > www.keyvis.at <http://www.keyvis.at> > This email and its attachments are > confidential and for the recipient only > > >
