Gummy Bear Progress: Week 1

Well it has been one week since I was tasked with coming up with my mentor project. I chose to create a simulation where a pile of gummy bears falls out of a bag and then melt and swirl together forming one giant gummy bear. In the past week, I have baked out an RBD sim of the gummy bears, and I'm using it as a seed for my FLIP fluid simulation. In the end I may end up doing the entire sequence as a FLIP simulation with varying levels of elasticity and viscosity, but for now my fluid simulations begin when the RBD objects are at rest.

 For the look of the giant bear forming, I wanted to have the fluid first swirl together and then lurch into existence. I wanted the fluid to look as if it were struggling to take shape and to have some organic movement. What I wanted to avoid was the FLIP particles flying to their final resting place, as though weightless. To accomplish this look, I'm using a combination of a custom force field in DOPS and a POP solver plugged into the FLIP solver. The force field is just a SOP geometry with a force attribute that adds a counter-clockwise force to swirl the FLIP particles around. In the POP solver, I put down an attractor that pulls the particles towards their final position (as the giant bear).




With the color channel enabled, we can see how the different colored gummies will mix together. One aspect that I really enjoy about this simulation is the way the legs of certain gummy bears tend to flail along with the movement of the liquid. I also think it adds some nice surface detail as the



To achieve this organic lurching effect, I animated the attractor's strength and added noise to the bezier function. I also animated the strength of the twisting noise.




At this point, the formation of the giant gummy bear is almost to my liking. The only remaining issue is the accuracy of the final shape, which right now isn't as close as I would like to the actual surface of the giant gummy bear. We're learning about FLIP fluids and custom fields tomorrow, so hopefully I will gain some insite into my issues.