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DarkMoon
03-13-2003, 09:56 AM
Hi,

I wanna create a scene on which there is fabric ( a satin sheet) laying over some boxes to create a kind of pedestal... kinda like you used to see on some product presentation shots.

I tried that once with motion desinger, without any luck, the objects always poked trough the fabric, no matter how many polys on the objects and teh "fabric". Followed all tutorials etc.. couldn't get it, exept when doing the exact same thing in the tutorials. :mad:

The fabric in itself will not be animated, just the camera rotating around it.
Any hints on how this could be acomplished without to much hassle?

Thank you in advance

PS: I'm Using LW6.5b

Rory_L
03-14-2003, 02:32 AM
You did try playing with cloth thickness, didn`t you?

If you really can`t get MD to work, then model the cloth in the draped pose!

R

DarkMoon
03-14-2003, 03:30 AM
I don't remember, it was awhile ago (for a different project). but I'll give t another try since it would look a lot more natural.

Thanx

Simon
03-14-2003, 09:01 AM
If the cloth hasn't got to be animated, get it looking sort of ok in Layout with motion designer, then do a 'save transformed' for the cloth object and you can tweak it/the boxes in modeller until your happy with it, and there's no bits sticking through?

DarkMoon
03-18-2003, 07:29 AM
Is there something going on in motion designer that breaks it when you have "sharp" corners, like on a box? Just wondering.

Thanx

Skonk
03-18-2003, 07:38 AM
I think Rory_L has it there, increase the thickness untill none of the box pokes through. But also Simon's idea wasn't bad, if u do it that way though i recommend doing it with a fairly low poly cloth (not in subd mode) then after u do save transformed take it into modeler, fix any bits where the box still pokes through then subd it. If u save transformed on a subd object it will freeze it and make it hard to fix in modeler while keeping it looking natural.

James..

DarkMoon
03-18-2003, 07:44 AM
Thanx,

I'm already doing this, I was justw ondering as to why MD behaves in this way.

Skonk
03-18-2003, 08:11 AM
Its hard to explain but its down to way it calculates collisions, i think it works on points, and not the polygons, so if u for example had 1 of the cloths poly's cantered over the point right at the corner of the box the cloth points hanging over the edge would fall down and swing onto the side of the box while the points at the top would stick to the top, u then get the polygon going in a diagonal direction between those points so the corner of the box would poke through (u cant have 1 polygon drape over a corner made up of 3 polygons without problems). Increasing the amount of polygons on the cloth would help a little creating a more accurate collision but it would never totally get rid of it (though it could make the effect so small u donít see it, but this would take an age to calculate) but increasing the thickness setting should put a big enough gap between the cloth and box to make sure u donít get any bits poking out. You do end up with a gap between the two objects but it should never really come into view.

Hmm, reading that back I donít know if I made much sense :) but anyway iv rambled on for long enough.


James..

DarkMoon
03-18-2003, 08:24 AM
Thanx...

It makes sense to me, but then I have been up for over 24 hours.... :D

DarkMoon
03-18-2003, 08:24 AM
So... subdividing the box(s) should help as well then?

Skonk
03-18-2003, 09:00 AM
subdividing the box wont help i dont think, tho it would increase the calculation time. Subdividing the cloth would help a little.

James.

Rory_L
03-18-2003, 06:55 PM
Both box and cloth. Ideally you want the mesh density to be about the same for each at the trouble spot. Well that was the conclusion I came to after mammoth experimentation with the old MD plugin for 5.6 :)

Show us your results, eh!

R

HowardM
03-19-2003, 09:00 AM
read up on these ( http://www.newtek.com/discus/messag...tml?1026744459 and http://forums.newtek.com/discus/messages/2/27478.html? and
http://forums.newtek.com/discus/messages/2/28051.html? )

Heimhenge
03-20-2003, 04:29 PM
Yeah, what he (SD) said ... you can't "drape" a poly over a vertex. But suppose you dragged the nearest vertex of the cloth object to where it coincided with the vertex it's draped over.

Wouldn't that solve the problem of pierced polys?

Skonk
03-20-2003, 05:41 PM
I guess that would help :) if you do that with a none sub-d object make sure to tripple it or it would cause a none planner poly, but with sub'd it should work. I think upping the thickness is the way to go though.

James..