Join EJ Hassenfratz for an in-depth discussion in this video Adjusting Dynamics and Expert settings, part of Mograph Techniques: Dynamic Falling Objects in Cinema 4D.
So, you'll notice that in our scene there's quite a bit of jitter when our coins rest upon one another. In this video, we'll eliminate that jitter by digging deeper into the dynamic settings. So, let's go into the overall project settings of the dynamics in our project by going to Mode > Project, and going to the dynamics tab. Now, here we have a whole new list of settings that affect the dynamics on a project wide scale. Now, under General, lets increase the time scale to speed up the dynamic simulation.
Right now, the coins are dropping slower than they would in real life. Let's bring this to about 150. Let's also increase the gravity in the scene to about 1500. So our coins fall faster and harder and come to a rest faster. Next we'll move to the expert tab, and adjust a few key settings that will help alleviate the jitter in our dynamics calculation. You normally never have to touch these first two settings so we'll leave those alone. The first thing I'll adjust in this tab, is the Restitution Lifetime setting.
This helps eliminate the jitter between objects resting on one another. Each object has tiny little springs that help it to prevent geometry. From intersecting from one another. In adjusting this setting to a low value, adjust how fast those springs deactivate, after the dynamic objects come to a rest. So let's set this option to a really small value. Something like 0.001. Now this random seed value is pretty handy if you don't like the dynamics calculation. Changing this value changes the random dynamic calculation numbers that are used to create the dynamic simulation.
And therefore changes the object movement as well. This is great for if you don't like the way some of your objects lie in a simulation. You can always change this value and get a slightly different result. With the main simulation aspects being the same, but we'll leave this at zero for right now. Now, to get a more accurate simulation overall we can increase these next two settings, steps per frame and maximum solver iterations per step. Steps per frame defines how many calculations occur for each frame.
So the higher the value, the more accurate the simulation, and the more you'll prevent oddities in your simulation, like geometry intersecting. Max over reiteration help make each step even more precise. So, normally, whatever you have in steps per frame, you just want to double that value for maximum solve reiteration per step. So, let's actually bring these numbers up. So, I'm going to change this steps per frame from five, to 20 and we'll double that value and change our maximum solve iterations per step to 40.
So I already prepared a ran preview to show you, our final result. You'll see when our coins actually drop and are on top of each other, they're finally come to a rest and we eliminated all that jitter. By adjusting some of those settings in the overall project dynamics settings. Now, keep in mind that, by increasing some of these settings. Like, the steps per frame in maximum solved iterations durations per step. You're also increasing the calculation time. So it's always good to experience how low you can get these settings, while still getting a pretty accurate simulation.
- Setting up an emitter
- Adding collider body and dynamic body tags
- Adjusting force and collision settings
- Baking the animation
- Rendering and finishing in After Effects