9.5.2

OBJECTS MENU • PRIMITIVES • 173
Primitives
All primitives on the Objects > Primitive menu are parametric, i.e. they are created from mathematical
formulae using a number of preset values. A consequence of this is that such an object is initially simply
a mathematical abstraction and is not editable. In plain language, this means that primitives have no
points or surfaces that you can manipulate.
For example, you cannot edit a primitive using the Magnet tool, because the Magnet needs points
to pull on. To apply polygon tools such as Magnet, you must rst convert the primitive to polygons
using the Make Editable command.
On the plus side, parametric means that you can change the parameter values of an object, such as
height or radius, at any time. This allows you to experiment with the different parameters of an object
in order to get a feeling for how it looks, behaves, etc.
However you choose a new object primitive, rst of all the relevant primitive is created in the scene and
its settings appear in the Attribute manager. To display an existing object’s parameters in the Attribute
manager, select the object by clicking its name in the Object manager or by clicking the object in the
viewport. Often you’ll see settings for segments; use these to dene the level of renement of the
particular surface or solid. This is useful if you are going to extend the object, perhaps to build further,
more complex objects.
Suppose you want to create a curved rod starting with a cylinder primitive. If the cylinder has only
one segment along its length, it will be impossible to bend it into a rod shape because there are no
points along its length that can be transformed into a bend. The more segments you assign to the
object, the more smoothly it can be bent or otherwise deformed.
In addition, most primitives use Phong shading automatically to smooth their appearance. This can
occasionally lead to problems when using chamfered llets, when smoothing is not desired between
the llet and the other object polygon. In such cases, override the default Phong shading setting
by assigning a Phong tag to the primitive (Object manager: File > CINEMA 4D Tags > Phong). You
can then switch off the Phong shading by enabling the Angle Limit option and setting the Phong
Angle to 0º. Since this removes all smoothing, you’ll probably need to increase the object’s number
of segments. Or you may nd that a low Phong Angle with not quite so many segments works just
as well plus more quickly. You may often need to juggle segmentation and smoothing to achieve a
balance between quality and render speed.