Introduction to MassFX
MassFX has an infinite amount of uses, but primarily it allows us to animate objects based on various input parameters using gravity and physics. The parameters allow us to define our objects as solid, soft, cloth, or liquid. The tool is extremely useful to scatter objects such as those displayed in Figure 1 or to create action in a particular scene to make it more interesting. This tutorial will focus on filling a candy jar with gum balls as shown in the holiday greeting I created for friends and family (Figure 1).
Figure 1
To begin, we simply create a jar. The particular shape does not matter, but the idea is that it would contain the gum balls without them spilling out. To create the jar, we simply draw a line representing the half of the outer silhouette and use the 3ds Max® Modifier “Lathe” to revolve the line 360 degrees around a center axis. The steps are demonstrated in Figure 2.
Figure 2
We’ll want to cap the bottom of the jar to ensure the gum balls don’t simply fall through. To do this, simply apply the Modifier “Cap Holes.” When applying this modifier, it caps both ends of the jar, which doesn’t allow us to fill it with gum balls. The final step is to apply the Modifier “Editable Poly,” select the Polygon option as shown in Figure 3, and erase it using the delete key on the keyboard. Finally, if you want to apply some thickness to your jar, simply use the Modifier “Shell.”
Figure 3
Next, centered directly above the jar we’ll want to create our gum balls. It’s extraordinary how many gum balls a jar can hold so we’ll want to be ambitious about how many to create. To create these I simply selected the Standard Primitive “Sphere” and copied them as instances as shown in Figure 4.
Figure 4
With the final step, we select everything and define them as rigid body objects. To do this, use the Animate menu -> MassFX -> Rigid Body -> Set Selected as Dynamic Rigid Body option. It’s important to note at this point that MassFX creates a theoretical copy of your options in order to complete its simulation. In order for MassFX to accurately define the shape of our jar (particularly with regard to the opening on top), we must change the MassFX Physical Shape Parameter Shape type to “Concave.” After changing the option, navigate to the Physical Mesh Parameter section and choose “Generate” as shown in Figure 5.
Figure 5
Finally, under the same MassFX menu we worked with previously, under Simulation, choose Play Simulation to view the results. If the results are satisfactory, Bake them using the option in the same location. You should get results similar to what’s shown in Figure 6.
Figure 6
