Environmental Animation - Blender Foundations: The Essential Guide to Learning Blender 2.6 - page 367

squash and stretch, etc. Lowering the Mass has the opposite
effect—the mesh is more immediately susceptible to forces,
but has less momentum.

Finally, if you're looking at both the shear simulation and
the flower petal simulation at the same time, you might
notice that the wind seems to affect them disproportion-
ately. For example, the amount of wind you need in order
to sufficiently drive the cloth simulation might be overkill
on the little soft body flower. The end result would be that
the shears appear to be disturbed by a gentle breeze, while
the flower is blasted by a hurricane.

Figure 13.10 The Soft Body Field Weights panel.

One solution to this would be to create a second wind object with scaled-down force levels and place
it only on the flower's layer, restricting the original wind Empty back to the shears' layer. Easier,
though, is to check out the Soft Body Field Weights panel at the very bottom of the soft body controls,
shown in Figure 13.10 . It holds a slider for each of the possible force types, and allows you to dial
back their influence on the simulation. Set the Wind control down to 0.5 (rule of halves!) and see
how it goes. Adjust accordingly until the flower and shear motion appear to be driven by the same scale
of force.

When you have the flower moving like you want, use the Bake control on the Soft Body Cache panel
so that the simulation is renderable. Without baking, you'll get somewhat random results when trying to
render.

Particles
You've already used Blender's particle system to create hair for our character. It can also be used for more
traditional particle effects, like “magic.” It won't find its way into the “final” version of the scene, but just
for fun let's give the thrown cube toy a sparkling trail as it briefly arcs through the air.

Select the cube toy and note the frames on which it leaves the boy's hand (117) and hits the table (145).
These will be the start and end points for our particle system. With the cube selected, bring up the particle
system properties, which are shown in Figure 13.11 . If you'll recall from generating hair, particle systems
have dozens of potential properties, and you could probably ill an entire topic with a breakdown of all
the options. We're going to show you how to enable a system, set its basic motion properties, and get it
to render.

Particles are emitted from the surface of their parent object, which in this case is the cube. The top panel,
Emission , holds the controls for the total number of particles, the start and end frames for their emission,
and how long each particle lives. Set the start and end frames to the frames noted just a moment ago, so
they begin when the cube is thrown, and end when it hits the table. The Lifetime property controls how
long particles remain visible. How long should the particles in our little simulation live? That depends on
the effect you are shooting for. As we're trying to make a quickly-dying trail, set it to 24, which represents