Adjusting the stretch and stiffness
Scroll down to the ‘Simple Soft Bodies' rollout and notice that you can adjust the stretch and stiffness of the object. All you need to do is hit ‘Create Simple Soft Body' once and then adjust the parameters. The changes take place immediately without having to repeatedly click the ‘Create' button. The stretch parameter sets how much the object can elongate whereas the stiffness determines how rigid the object is. Play around with the settings and see how it affects your object.
Fine tune how your object relates to the flexing process by adjusting its stretch and stiffness parameters
An introduction to forces
So far we've focused on ensuring that our objects flex based upon their velocity. We are also able to create forces like wind, gravity and drag. We can cause these forces to act upon our objects, saving us untold time having to key frame it. So for example, say you have a windy day and a bouncing ball that flexes as it bounces, you might also want the ball to be affected by the wind in the environment. This is achievable with a few straight-forward steps, as we'll come to see.
There are a range of forces that you can choose to affect your objects
A ball on a windy day
Create a sphere and apply the Flex modifier to it. Head over to the create panel and to the Space Warps section. Select Wind and click-and-drag in the viewport to create your wind gizmo. Adjust the wind parameters Strength and Turbulence to something like 6 or whatever suits you! Then select the Flex modifier on the sphere, go down to the Forces and Deflectors rollout and click the Add button in the Forces group. Select your wind gizmo and play your animation. And there it is, a wobbly ball. Magic!
Here we see a perfect sphere totally transformed by the wind gizmo. In only a few steps you can set up the same thing
A falling ball
With your ball affected by the wind let's add a gravity force to it. Go back to the Space Warps section and select Gravity. Click-and-drag in the viewport to create the gizmo. Select the Flex modifier again and head down to the Forces and Deflectors rollout. In the Forces group add the Gravity force. Adjust the gravity strength to see it take effect on your ball.
You can apply multiple forces to a Flex modifier. Here we add a gravity force on top of the wind modifier we added earlier
An introduction to deflectors
Now we're going to move on to look at using deflectors in our simulations. It is often helpful to not only apply forces to objects but to also have those objects interact with surfaces. There are plenty of applications such as throwing an object against a wall, which we'll look at in a minute. There are a range of deflector choices but the key to getting good results is to ensure that the bounce is low and the friction is high. This will cause your object to collide and stick to the surface. Let's look at an example.
There are plenty of deflector choices to choose from. Use the 3ds Max help section to see the application of each
Splatting a ball against a wall
This is more fun in real life but it's still fun in 3D! Create a sphere to represent your ball of goo and apply a Flex modifier to it. Head over to the create panel and to the Space Warps section. Choose deflectors from the drop-down. Select Deflector and click-and-drag in the viewport to create your gizmo. Now key frame your ball moving through your deflector. With that set up, select the Flex modifier on the sphere, go down to the Forces and Deflectors rollout and click the Add button in the Deflectors group. Select your deflector gizmo and play your animation. And there it is – a ball splatted on your surface!
Here we see the ball moving through time and as soon as it hits the deflector surface it deforms and splats. Great fun!
Top tip: Always experiment
There are loads of applications for the Flex modifier. If you ever find yourself key framing something that is natural in essence, think about using the Flex modifier along with forces and deflectors.
Here we have a load of random rock formations only made possible through the Flex modifier and the wind force
Improving your 3ds Max workflow – previous chapters:
Top 10 interface secrets
Better modeling workflow
Handling massive scenes
3ds Max animation tools
Organic placement using MassFx
An introduction to Particle Flow
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