I am trying to model a “Vacuum Packed Meat without Tray Inside” package, like the ones in the following example. Packaging must have the same creases / folds as the real ones. More like the third.
I have already tried to create using physics simulation and cloths, creating a large object like a cloth on the outside and a collision object on the inside and using a force with negative value (Strength: -100) within the cloth object. But the packaging does not look like it is in a vacuum. The following figures show these attempts.
Another alternative I tried was using shrinkwrap, but with this modifier the packages are without creases and without folding.
The major problem in these cases is that the outer mesh does not wrap the inner object in the spans as it should. The outer mesh should wrap the inner mesh in each gap, in each corner, while maintaining its volume. As if the air inside the mesh had been sucked all over. And inside the mesh there is no air, so it surrounds the entire inner mesh.
I already tried add-on like Modeling-Cloth but the results are similar.
What would be the best way to model this?
Can you help me ?
I’m using Blender Render Engine. My main intention is to recreate the folds true to the real shapes.
I
Place the meat model in the center of the scene and create a flat Plane bellow it and the “Package” sized subdivided Plane above it.
Simulate cloth on the “package” Plane with meat and flat plane set to Obstacles. Make sure to add a strong wind above the meat blowing on it. This will give you perfect top package shape.
Repeat step 2 for the bottom package but instead of the flat plane use the top package shape.
Pretty sure it is impossible to do with a cloth sim. I would try to model by hand the large characteristic kinks and bends, and in particular the foil folding back onto itself. The general wobbliness can be done (ant tweaked) with a displacement modifier (maybe a clouds texture already suffices).
Switch of gravity. Do whatever shape of the package you want. Make the meat a collider. Make the packing a cloth. switch on self collision for it. Put a force field inside the meat. Go to force field settings, set the strength to negative. Run the simulation. Play. Try more fields/different cloth settings. Good luck
So I’m not overly familiar with Blenders Cloth Sim any more, it’s been a long time since I’ve used it. But it should be a decent starting point at the very least.
A few things to consider. A lot of the wrinkles in the plastic come from the shape of the meat. What you have is a very flat and ‘perfect’ shape, so the cloth is going to conform to that shape pretty smoothly, because it’s following what you’ve given it.
Something else to consider is that meat isn’t dry and slippery. It’s sticky almost, so that will attract the plastic in interesting ways. I’m not sure if you can add wetness to the collision object (Dampening I think??) but if you can, definitely do that.
I’m not sure you’re going to get it from the Cloth Sim alone, but as I say, with some tweaks, you should be able to get a good base. I’d then honestly recommend just sculpting some of the additional geometry in, and then if neccesary, retopologise after, and/or bake the normals.
Interesting idea. You would need to pin the border vertices of foil, use stiffness scaling, or some similar trick to prevent the outer part of the foil also being pulled in compietely.
omgold, indeed, It’s a pity Luca Rood didn’t commit his pressure code to cloth sim. It would help so much in modelling. But the forcefields ‘kindof’ work. I tested it many times.
Yeah, sounds like a helpful feature. Thanks for pointing that out. Sometimes there is actually cool new stuff appearing. I also wished for negative shrinking factors, or maybe even better using a shape key as ‘reference geometry’, to make crumpling easier.
I was able to get something without much effort using the Modeling Cloth addon. To be fair, I probably understand it better than most people.
I create a meat-shaped object with a flat spot around it to catch the overlap. Set that to collider.
Next I made a plane a little bigger than the meat and subdivided it.
Set the plane to modeling cloth and and used gravity to make it fall.
Once it was laying over the meat, I scaled the source shape key up around the outside edges so it would create some wrinkles.
Last I put on a corrective smooth modifier to fix some of the weirdness.
I imagine I could get better results with a little time and effort.
