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fronzel
10-14-2005, 08:23 AM
first image is the shape that this ribbon should end up at when its done flying around.

and the second image is the shape it starts out as.

they want it to look like silk billowing in the wind.

and to make it even more complex they got this gay texture on there too.

yikes this is going to be hard. Any ideas ?

I'm gonna have more specific questions soon I'm sure.

Celshader
10-14-2005, 10:06 AM
Hm. You could play the MDD file backwards for a reverse-photography effect. Set the Playback type to "Local" and the Speed to -100%, then set the start frame to the same number of frames as the calculation. If the calculation's 300 frames, set the Start Frame to 300. Then the MDD file will play backwards, starting from frame 300.

In this way, you can start the calculation from the neat-ribbon shape and let ClothFX blow it around at random.

---

If you use a morph target to sculpt the ribbon, and the "base" shape of the ribbon is flat, then you can texture the ribbon with a planar map. In Layout, morph it 100% to the looped shape on frame 0 with Morph Mixer.

On top of that, you can turn off "Relax Start" so that ClothFX considers the base shape of the ribbon in Modeler to be the "true" shape of the ribbon, instead of the morphed shape on frame 0. That way, it won't try to maintain its looped shape as it unfurls.

$0.02

MonroePoteet
10-16-2005, 04:12 PM
You might experiment with Textured Displacement and Normal Displacement using a moving Turbulence procedural on a subpatched ribbon for "billowing in the wind" rather than using cloth dynamics.

Create the flat ribbon, UV-map the texture and subpatch it. Copy it to a new object and modify the geometry into the curved ribbon. You could create intermediate models for curving the ribbon around as well, if you want.

Bring both into Layout, setup the curved ribbon as the Morph Targe of the flat ribbon. Apply the Textured Displacement and Normal Displacement to the flat ribbon, and adjust the speed of movement in the Turbulence texture to get the billowing you want. When you morph to the other object, the billowing goes away.

There's probably a way to only apply the displacements to one endomorph within a single object, but the two objects may be easier to set up.

mTp

fronzel
10-16-2005, 04:13 PM
Thanks for the help! Celshader! this is'nt the first time you have helped me out.

So now I've got the animation roughly were I want it and the flowers image mapped on correctly.

I just can't seem to figure out how to keep the scarf from colliding and intersecting with it self.

the collison tab on the cloth effects panel does'nt seem to do anything
and I've got the sub structure at 20k guess i'll keep tweaking these to things untill it works

Celshader
10-16-2005, 06:12 PM
Glad to be of help. :)


I just can't seem to figure out how to keep the scarf from colliding and intersecting with it self.

After activating Collision, make sure Self-Collision, Double-Sided Collision and "Connected" are all turned on. Self-Collision lets a ClothFX-deformed object collide with itself; Double-Sided means collision is detected on BOTH sides of a polygon, not just the side with the normal; "Connected" allows a contiguous mesh (like your ribbon) to self-collide.

Also, try increasing the Collision Offset from its default of 10mm. This will increase the distance from which a point will bounce off of a polygon, and it can help reduce intersections.

fronzel
10-20-2005, 07:56 AM
So what I finally did to get the scarf to unfurl nicely, was apply a weight map to the weight Fx tab in the basic clothFX tab.

I made the weight map when the object was unfolded. So it looked like a long peice of tape or ribbon. 50% to 100% weight gradient from one end to the other then I morphed it to its end state then set that as the base object. threw out the morph. and played the render backwards to get it to land in this shape.

Thanks again!