Fluid and Rigid Body [simulations]

Since I’ve been at home more or less all day every day, I’ve found that I have time to experiment with some liquid and rigid body simulations; since it takes so long to calculate and bake the physics into the scene, and then render them out to images.

These are all rendered out as still frames, and are so satisfying to watch when they’re all pieced together as videos – I’m currently aiming to have around 15 short simulations of different types before I compile them into a YouTube video: for now though, I wanted to share some single images and get back into posting regularly here.

The finished video

What are they?

These show simulations of how gravity and collisions affect solid objects (and in the case of the first three images, liquids)
The effects in the other images show a stack of how gravity would affect a set of 12×12 cubes being dropped, having things thrown into them, having coloured balls dropped onto them and the surface they are resting on moved out from under them.

Fluid simulation

I liked the splash effect on this, but I’d not set the liquid in the jar to the right, transparent material, so it does not ripple or move like water would.
Water drop (Eevee renderer, preview bake)
This will show a simplified form of how the water will react to the object that causes the splash
Water drop (Eevee, higher resolution bake)

Rigid body simulations

In the last four images, I’ve used some HDRI Maps as the background: these are panoramic images with lighting data embedded into them, so that they affect the lighting in the scene, making it look more natural than it would if I used artifically placed lighting.

If you look at the image above, the floor is a glossy, reflective surface, but you can see the reflection of the horizon and sky on it – if you look even closer, each individual cube has a slight reflection on it from the 360° scene background – so even if a cube is facing us from the cameras perspective – it will show the reflection of the background behind the camera; and this updates in realtime as it scatters, rotates and tumbles around the simulation.