Join Steve Nelle for an in-depth discussion in this video Working with the Soft Body Modifier settings, part of Learning Reactor in 3ds Max (2011).
When used in conjunction with a Soft Body Collection, the Soft Body Modifier offers a powerful set of controls that allow you to change the way a soft, pliable object flexes and bends. That's exactly what we're going to need to do on our project's bat and ball: tweak the numbers a bit to get just the look that we're aiming for. To do all that, we'll be using the Soft Body Maize02 scene file that was saved at the end of our last video. Why don't we start by first fiddling around with the Soft Body Modifier settings that we have controlling our ball.
We'll select the ball in the view, then head over to the Modifier column. Irrespective of whether you've decided on using a mesh-based or FFD-based method to calculate your deformations, the Soft Body Modifier offers four primary property controls in order to change the way your Soft Body object responds to coming into contact with something else in your scene. The one right at the top of the Properties tab, the Mass setting, affects an object's behavior at the time in which it collides with another surface. For this particular sim, changing that number around quite honestly doesn't do a heck of a lot to alter our outcome.
So with that in mind, we'll leave this setting at its default value of 1 kilogram. What will make a difference as to how things look is the Stiffness setting, which is used to control just how stiff or how rigid an object appears during a sim. Now you don't need a huge variance in the value in order to noticeably affect the turnout. So we'll keep the number low, changing the Stiffness from 0.2 to 0.6. Before we do our previews, as a way of speeding things up being that right now we're only looking to adjust the responsiveness of the ball, let's temporarily remove the rubber bat from our simulation.
We can do that by selecting the Soft Body Collection icon on the scene, then on the right-hand column choosing Rubber Bat in the list. Once we've made that selection, we can go ahead and click on the Delete. Doing this won't delete the wireframe bat from a scene; it's meant to only remove it from the Soft Body Collection. Let's check things out with a preview. Once the Preview window is opened, let's go up to Performance, changing our substeps to 3.
Now we can go ahead and play things back, typing P on the keyboard. Now, that's awfully bouncy. Let's take the ball's Stiffness back to around 0.4. And with the changes made, we can now run another Preview.
Back on the right, Damping determines how long it takes for a pliable surface to return to its original shape, lower numbers having the affect to the object taking longer to return to its initial look. To show you how damping would affect our ball, let's the value to 0 and see what happens. With the ball maintaining its original shape pretty much from start to finish, you can see how it really bounces around from one object to the next.
Let's see how a Damping value of 0.4 would look. Before we run our next preview, let's first change the substep value over in the Utilities column. By typing the number in there, we'll permanently lock things down into that lower value. Once we're in the column, we'll head up to the Preview and Animation section. Then to the right of Substeps/Key we'll type in 3. While we're over here, let's go ahead and use the Preview in Window command directly below that.
So with our Damping control set to 0.4, you can see things look a little more realistic. Back to the Modifier column settings on the right, Friction will determine how our ball will either slide or grab onto a surface that it comes into contact with. Let's take that number down to 0.1 and see how things turn out. With less Friction and grab, you can see how the ball continues to slide right off the side of our scene. Why don't we also try Friction value at the opposite end of the spectrum? Like 1.
And we'll see how that looks as a point of comparison. Boy, what a difference that made! Once it's done colliding with the other objects in the scene, it pretty much stops dead in its tracks. After all of our fussing around, things will probably look best if we simply keep our default setting on our Friction at 0.5, so let's go ahead and take that back.
For the bat, let's see what we can do with that. Like we did when working with the ball, let's again temporarily remove from the sim the object that we're not using. So we'll go back and select the Soft Body icon. Then back on the right, we'll select ball, then click Delete. Now to pick the bat up, we'll click on Pick and then directly in the scene, we'll click on the orange bat. When you're done with all this, go back on the right-hand side and verify in the window that it only reads Rubber Bat. Let's run a preview on this.
So on playing things back, the bat drops pretty quickly. Let's close our Preview window, select that bat in our scene, and head on over to the Modifier column. In the settings, let's start by changing the Stiffness to 0.7, then running a preview. This obviously creates a problem. The evaluation with the Substep/Key set at 3 is using too few calculations to offer a credible preview.
So here's a situation where we'll have to take the substep number back up. We can do that temporarily by changing the Performance directly inside our window. When the menu opens, we'll change from 3 down the 6 substeps. Let's run our preview again. So isn't that something? That's all it took. Let's also crank the Friction up a bit. We'll take the value to 0.75. Getting back in the Preview window and changing our subsets back to 6, we're run another sim.
Now with the higher Friction number, you can see that our bat is definitely holding on longer to the surface as it comes into contact with. But I think the way things turned out, that's going be the look we're aiming for. So that'll do it for our Soft Body Modifier tweaks. Let's save things up as Soft Body Maize03, and we'll head into our final project video, where we'll make a few concluding adjustments and create our keys.
- Choosing the appropriate collection type
- Using the Property Editor to set up an object's physical properties
- Working with soft body modifiers
- Accessing and using the Reactor toolbar
- Making objects appear soft and pliable
- Using constraints to limit object movement
- Animating objects breaking apart
- Creating realistic water using a reactor helper object
- Previewing simulations
- Controlling simulation accuracy
- Creating keyframes for a dynamic simulation