dForce issue: Flyaway and nonsensical behavior during simulation

Rakuda

The reason for this post was to solve the issue presented above with unattached tassels not simulating satisfactorily even though I weight-mapped their ends to not simulate. I guess that doesn't work so well for unattached elements.

 Here is an image of the rug geometry of a rug that I am trying to simulate. It is possible that I could add a bit of resolution to the geometry running across the rug side-to-side. The tassels are unattached geometry. It may be easier to try to just attach them. Naturally, attaching them, would add more geometry to the rug itself.

I created a new rug with attached tassels but dForce didn't like it at all. Here it is below.

Second try:

When I added dForce Modifier: Dynamic Surface and simulated it, it went completely wonky and shrunk down to a simplified geometry square.

 

Rakuda

Here for info sake is my .obj file in zip format or just OBJ: rug_new.obj, or Hexagon: rug_new.hxn.

Richard Haseltine

If you weight the tassels to be less or non-dynamic then they won't move at all, while the rug will. There isn't a way to keep them together with the adjacent mesh if they are not actually attached, unfortuantely.

RGcincy

@Rakuda thanks for posting the .obj file. I imported it, added a dForce modifier and ran a single frame animation with Start bones from memorized pose set to off. Simulation settings were default as were the surface settings. It draped fine but slow (even though I'm using GPU). The edges of the box show through but that can be handled post simulation by a small scale change. You can also add a smoothing modifier. I didn't play around with any surface setting which may avoid the need for scaling.

Here's what I got:

After simulation:

After scaling to 102.5%:

After simulation and adding smoothing modifier:

After scaling to 104%:

Not sure why it's behaving differently for you. If you haven't, perhaps shut down DS, reopen, import the rug again, and add fresh dForce modifier (no weight map).

Rakuda

@RGcincy Just Wow! Yes, I will play with the settings and  run again. I will set it up in a new file, but all in all, I have to say, the result that you got looks fantastic! I am totally amazed! Probably slow to simulate because there is a bit of geometry resolution in the tassels adding up to a bit larger file size.

Rakuda

Ugh, I followed your instructions and am getting the same crazy behavior. Maybe I need to do a screen capture video and post on YouTube. Are you doing anything like converting the geometry to subd geometry? Hope I don’t need to reinstall DS. I do have my content directories on an external drive, but my executables are in the standard directories.

when you start the simulation does it usually run a dialog that iterates through a sequence listing:

Spring(13245,12345) of node “rug_new” extended:rest length < collision offset  (0.012344 < 0.274658)  

For me it does that for about 10 minutes first before it actually begins physically doing the simulation (Stabilizing Simulation)

barbult

@Rakuda, your rug imports to Daz Studio and simulates fine for me, too. I let it drape on a primitive sphere. I scaled the rug up by 500% to fit my 1 meter sphere. I applied Carpet Measured material from the Default Resources product. I added dForce Dynamic Surface to the rug and used the default simulation settings. I'll attach the render and the scene for you to examine. I got the messages about the "springs", too. It happens even with dForce items sold in the store. I don't think that is the cause of your problem, but I don't know what is. How did you import the obj to Daz Studio? I'll attach a screen shot of the settings I used to import your rug obj.

barbult

@Rakuda, I wonder now, whether your problem is caused by importing the rug at a small scale. As I mentioned, I scaled it up by 500%. If it is too small, it will trigger more of those spring errors messages, because the mesh for the fringe is so close together (closer than the default collision distance).

Edit: Well, I tried simulating it at a small scale, and I got a bazillion spring messages. Then it disappeared completely when the simulation started. I suggest making it larger and then simulating. Make it rug-size. 

Rakuda

@barbult you may have been right about the scale. I was able to use your file successfully. And modify it to re-simulate. 

That did solve it to some degree, but I do notice that if I appply the dForce presets in the "dForce Master - Cloth Simulation Presets" set such as the weight of jeans fabric, the simulation no longer completes. I need to investigate what changes beyond it switching the bones to memorized pose "ON".

Even toggling that back after applying presets. the simulation will no longer complete.

 

barbult

Rakuda said:

@barbult you may have been right about the scale. I was able to use your file successfully. And modify it to re-simulate. 

Thad did solve it to some degree, but I do notice that if I appply the dForce presets in the "dForce Master - Cloth Simulation Presets" set such as the weight of jeans fabric, the simulation no longer completes. I need to investigate what changes beyond it switching the bones to memorized pose "ON".

Even toggling that back after applying presets. the simulation will no longer complete.

 

That looks very nice. I like the texture a lot, too.

barbult

I'm having fun playing with your rug. I draped it over a chair as a throw. 

 

Rakuda

@barbult that is a really sharp looking texture. The throw lays gorgeously across the chair. Looks like a very useful rug/throw.

It appears that I should team up with some others who are good at building textures to knock some of my modeling projects into the next level. That image looks really sensational. I am interested in building some really quality content and eventually selling some in addition to sharing some.

thanks for sharing your render!

^__^

Rakuda

Richard Haseltine said:

If you weight the tassels to be less or non-dynamic then they won't move at all, while the rug will. There isn't a way to keep them together with the adjacent mesh if they are not actually attached, unfortuantely.

Hey, @Richard Haseltine

I forgot to say thanks for the helpful suggestion, I am so glad that with the help of others here, the solution was able to be worked out... and beautifully.

:)

barbult

Rakuda said:

@barbult that is a really sharp looking texture. The throw lays gorgeously across the chair. Looks like a very useful rug/throw.

It appears that I should team up with some others who are good at building textures to knock some of my modeling projects into the next level. That image looks really sensational. I am interested in building some really quality content and eventually selling some in addition to sharing some.

thanks for sharing your render!

^__^

I simply applied a knit fabric shader.

For texturing purposes, it would be nice if the fringe were a separate material surface.

maikdecker

When your rectangular carpets/rugs get boring, start experimenting with circular ones... lots of fun guaranteed!

Rakuda

barbult said:

I simply applied a knit fabric shader.

For texturing purposes, it would be nice if the fringe were a separate material surface.

@barbult. LOL. Had a few too few hours of sleep the last few days. I get a little too ecstatic on lack of sleep... But anyway... good stuff!

@maikdecker I was trying to picture that... Came up with this on Google, which would be interesting. x-D

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Update: Here is the cloth rendered in context of my setting.