Step by Step SIMULATE the Motion of A JELLYFISH
01Go Model the Jellyfish
to the Polygons shelf and create a sphere. Keep its Height subdivisions low, around 8-10. Delete the lower half. Scale it up in the X and Z axis – when looking from the top in scale mode, you’ll see a small square, use that. Extrude the edges on the bottom and drag them downwards as you want. Now, on the newly created polygons, delete every other face. You’ll end up with a cylinder of sorts.
02 Animate the Jellyfish
I animated the jellyfish so that it would go directly up. In my example, using a 200 frames timeline, I moved the jellyfish up (in the Y-axis) by 20 points in 20 frames. In the next 20 frames, I moved the jellyfish down by 5 points. Then again, in the next 20 frames, moved it up 20 points, so on and so forth. It’s pretty simple – just look at some reference footage if you need more help on this.
03 Jellyfish AS ncloth
Select the jellyfish model, move to the FX module and select the ncloth menu bar. Click the Create ncloth button and you’ve turned the jellyfish into an ncloth. Go to the Nucleus node and play with the settings there to really sell the effect of being underwater. Under some conditions, this might not even be needed – enable Ignore Solver Gravity in the ncloth node and it’ll pretty much work. Again, it depends on the scene.
04 find the Middle Ground
One thing that you might have noticed is that once you turn the mesh into ncloth, it loses the original animation. One way to solve this is to go to the ncloth node, and under the Dynamics tab, dial the Input Attract Mesh to .8 or so. Now go to the ncloth tab in the menu bar, go to the Paint Texture Properties and then click Input Attract. You should now be able to paint what part of the mesh you want simulated.