Bed scene physics [dForce]
faonkenstein
Posts: 20
Hello,
I am doing a bed scene video with an animated genesis 8 figure sleeping. I'd like to make his body slip into the mattress and his face into the pillow with a smoothing modifier but the results are totally weird and unnatural. The area pushed by the figure is always too large and he always gets through the surface during the animation. Is there a way to obtain a more realistic result based on physics, using the volume and the density of the mattress and the pillow instead of only a surface and make them collide with the figure ?
Above the figure, I am using a dForce sheet, but when the character moves too much underneath, the result of the simulation becomes weird too.
If someone has a solution or a tutorial to make this simulation more realistic, it would help me a lot !
Daz 3D is part of 
Connect
DAZ Productions, Inc.
224 S 200 W, Suite #250
Salt Lake City, UT 84101
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2024 Daz Productions Inc. All Rights Reserved.
Comments
smoothing modifier will not work.
dFormers will create the indentations you want in the bed and pillow, it will take some experimentation and a lot of dFormers but it would work as a single frame. If it will work in an animation I have no idea.
Best resource is this thread : https://www.daz3d.com/forums/discussion/208141/how-to-use-dforce-creating-a-blanket-draping-clothes-on-furniture-and-much-more-commercial/p1
There is a whole section on your issue, should give much better results!
I can come with some additional suggestions.
A) Add dForce modifier to bed and pillow. Set gravity to 0. Use abinated timeline with your character abover the bed at frame 0, and lower the character into the bed at (maybe) frame 15. Weight paint of the dForce modifier can be done if needed.
B) Get https://www.daz3d.com/mesh-grabber and manually adjust verteces to your liking.
Thank you !
I will try all this ideas !
I think daz3d is powerful to generate images but more complicated for animation without a real physics environment...
One thing you may run into is that the bed mesh might be too low resolution to deform "nicely." Getting realistic looks for this kind of thing requires at least a moderate mesh density, which many props don't have because it's otherwise unnecessary.
So it may very well depend on the bed you use.
Looks like your mesh is far too simple, for the matress at least, you need more polygons.
Also most issues i've had is with the surface properties being too stiff to create a decent deformation, which is why the static objects push through the dynamic objects. You will have to play with the settings. They are in the surface properties tab, below the material properties.
I have yet to see dForce being useful for animations, maybe it works in this case, maybe not. I also recall seeing somewhere that the mesh grabber does not yet support animation. I would definitely not try forcing the mesh by using the smoothing modifyer either, IMO dFormers are the way to go. And ,as others already mentioned, first find a nice mattress/bed with a good topology. The good thing about dFormers is that the field, base and dFormer can be animated independently...
I am trying the Dforce tools and the simulation is really better than yesterday for static images. Thank you for the tutorials links !
The character really sinks into the mattress and the pillow. It's a little bit hard to add wrinkles to the fitted sheet without making it inflate because of the reverse gravity, so I will maybe add a wrinkled texture to the object to make it more realistic. I added in the simulation a mattress shape underneath the sheet slightly deformed by the pressure.
Tomorrow I will try to add the blanket to the simulation.
That looks pretty convincing @faonkenstein ! Good progress!
Hello,
I did a lot of work on the undersheet to add more wrinkles ; I sculpted it in blender, created a new weight map and reajusted the surface parameters to obtain something more realistic. You can see the results on the attached picture.
Now I have a new challenge on this project : the duvet. Indeed, the simulation settings are in negative gravity to obtain that kind of results as described in the tutorial above. To make a sheet fall on the character, I can freeze the simulation of the bed, and launch it for the duvet with a normal gravity, but the result is very flat. And I would also prefer only one simulation rather than two to save time.
I'd like to simulate more a duvet than a sheet, so I need to pump it up ; according to the tutorial, the best way to achieve this result is to keep a negative gravity (it's the technique employed for the pillows). But obviously, with a negative gravity, the duvet flies away like an helium balloon. How could I keep the duvet fluffy but still make it falling on the character to wrap him ?
Thank you for your help
If you haven't already, check out the new Cloth Brush coming soon in Blender 2.83 and prepare to be amazed.
This brush looks amazing ! I used the free samples from poliigon https://www.poliigon.com/search?type=brush to build a pre-wrinkled sheet for the simulation.
Could you use ManFriday's MeshGrabber https://www.daz3d.com/mesh-grabber to fix the rough spots?
Though there are tricks to expand the dforce domain, remeber it's a cloth engine, that's not intended for anything else. If you need a full simulation solution with soft and rigid bodies plus fluids, you may like to export your assets to blender and work there. Personally I do recommend it for animation and effects.
Man, that looks pretty doggoned good... more than one way to skin a cat, I suppose.
One way might be for you to set a timeline and keyframes, set the sheet above the bed on the first frame and below the bed in the last (or middle) frame. Make sure the surface parameters are correct for decent deformation. Note, it will explode in all or part if your offset distance is bigger than the polygon line lengths. Then create a geometry shell of the final sheet, and export the sheet and shell to another program to join the edges together, if you need to. I'd use a duvet bump/normal map.
Not sure about doing everything in one pass, you can always export and import the finished simulations in seconds, which also gives you an automatic backup.
Finally I think I will keep two different simulations with a script to do everything in one click, if I achieve this code : https://www.daz3d.com/forums/discussion/385396/simulation-script#latest