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Chapter 3: Animation Techniques
— Figure 3.21: More settings in the Rigid Body Dynamic tag.
only be achieved in the Full setting, where all faces are actually evaluated for collisions. In our case the Box setting should be sufficient since we only expect collisions on the front and back of the pendulum. The elasticity determines the amount of energy that will be passed on between colliding objects. My tests have determined that 300% is a fitting value. You can start with a value of 100%. The values for Static and Dynamic act like a brake. The Static holds an object on a surface even if the surface is slightly tilted. Only when the tilt becomes too much does the object start to slide. At this moment the Dynamic comes into play because it only af fects objects already in motion. Other settings on the Aerodynamics page take effect only when the object is blown upon by the Wind object, which can be found in the Dynamics menu of CINEMA 4D. The many parameters define the buoyancy and the resistance of the object. This can be interesting should you want to animate an aircraft wing or a leaf with the force of the wind on it. In practice, though, this can hardly be planned because of its unpredictability. The start settings define the start state of the object in the beginning of the simulation.
The object isn’t always sitting still at the start of the animation. With the v values you can define a start speed. The speed consists of X, Y, and Z values because speed doesn’t have only a value but also a direction. The same is true for the start force that is defined at the letter F. This force only acts in the first image of the animation and can be used to push the object. The w values define the strength of the start rotation, and the I values determine a torque. Just like the F force, this affects only the first image of the animation and could be used to start, for instance, a carousel. Adding Two Cubes
In order to put the collision detection of the pendulum to good use and so it doesn’t just swing back and forth, we will create two new Cube primitives and resize them to a size fitting for the pendulum. I used a side length of 58 units. All objects used with dynamics have to be Polygon objects. Therefore, our cubes have to be converted with the (C) key. The cubes should be placed in such a way that a collision with the pendulum is certain. Figure 3.22 shows a possible arrangement.