Experiments with cloth

[Kzanna]

In theory everything is simple, in practice the cloth can behave very strangely especially when you turn on Self Collusions. Compare how the fabric lays on the cube (in the video with Self Collusion turned on)

![Screenshot 2023-10-26 225626|430x317] (upload://tbdOFGUOtgPaHsBzDZQj0A8oHMy.png)

After I wanted to cover the body with fabric. (October, Halloween, you get the idea). The cloth was pulled into the body and curled up inside

Not right away, but I thought to check the normals. The whole body was red. Great, the error has been fixed, let’s try again!

Better, you can find a good option, but the fabric intersects with itself. I dared to turn Self Collusions on. Bad idea. Funny result.

I also tried to create a classic ghost out of a sheet. Unfortunately, the folds are unrealistic.

My conclusions: The topic needs to be studied more seriously. And it seems to me that Self Collusions gives the fabric its own life.

[Breagha]

What I found while playing around with the stairs example in Stephen’s video, is having a floor that also has collision. It stops the sliding

I experienced the weird self collision crumbling too… I don’t remember how I made it stop, though x.x

Did you give it a solidify modifier?

[NP5]

Might it need more friction? Looks like it slides off as it has enough weight to keep going.

[FedPete]

Most people think with Blender, “When I turn this option on, it will work!”.
Nope, Blender is simulating physics by math but also by assumptions, as in the many properties you can fiddle with.

That last part “Fiddling”, is the most difficult one

You did a good study!

[StephenWoods]

I must admit I very rarely use cloth sims, it’s usually a lot of experimenting with settings and some luck for me

[Kzanna]

@Breagha The floor does changes things a bit, even then the cloth doesn’t reach it. Strange…
I give it a solidify modifier in the end (if I didn’t forget).

without Self Collusion

with Self Collusion

and lighter

@NP5 changing friction didn’t help. But then I noticed in the next line “Distance”!
0,015 → 0,001 and look at the result!

Only the cloth still intersects itself ((( I thought that more faces would improve the situation, and applied a subdivision. The result was unexpected…

@FedPete You are right. The computer works with numbers, it doesn’t care if the stone wall curls into a donut. And the more parameters we can control, the more accurate the result we can achieve. If you know what and how))))

@StephenWoods Your lessons on creating materials had more about creating fabric than I knew before. And then I can always find more specialized lessons, or experiment. The last one is pretty fun.

But perhaps I’ll stop for now and return to the materials. The lectures are very interesting and useful. And the lesson on creating a personal library is absolutely invaluable (I’m already tired of appending materials from previous files).

[Breagha]

Looks like a skirt in that last one

Last question/suggestion (unless it really bothers you, then you might try to share the .blend?): Did you remember to apply scale and rotation before putting the simulation on? It might get rid of some of the issues?

[Kzanna]

question and suggestion always appreciated

I try to always apply transforms, and prefer change form in Edit. In this case scale and rotation was 1.

I didn’t save the “skirt”, but it turns out the trick is easy to repeat.

[NP5]

Well discovered that the distance parameter made a big difference.
Basically this is how most people use nodes and such like, just play with things, see what happens.
Subdiv messed it up but, carry on trying other random parameters that may help it to work.

However bear in mind Blender’s physics system is known to be poor and in need of updating, apparently there just is no volunteer physics ‘nerd’ who wants to do it. Sadly.