6.1.3 Bouncing Sphere
As you have probably already noticed, the PATH method can produce
accelerations and decelerations according to distances between
subsequent knot points of the parameter curve used longer the distance
for defining the motion. The between subsequent knots, the higher the
speed and vice versa.
This example shows one advantage of the Real's animation system: all
information needed for animating objects is a natural part of the
object itself. When duplicating an object (e.g. bouncing sphere), all
animation data will be duplicated as well, ie. the result will be two
bouncing spheres. Bouncing spheres (or any other animated objects) can
be saved and loaded back and they still continue "bouncing".
To create a bouncing sphere:
1. Create one sphere to the top left edge of the window.
2. Now we define a motion for the sphere, as shown in the following
picture. Select the function Animate/Create/Path and draw a B-Spline
control polygon curve, which defines the motion for the sphere. By
creating triple points, it is possible to define zero speeds;
therefore, click the three first control points to the center point of
the sphere so the speed of the sphere in the beginning will be zero.
The deeper the sphere falls, the higher the speed ie. longer the
distance between the control points should be. Finish the curve by
<RMB> click.
3. REAL 3D creates a level under which it puts the sphere and the method
with its parameter path. Rename the new level object as "Boing".
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