TRANSFORMATION

So far, you have learned about 3D objects, the Cartesian coordinate system, and the

difference between object space and world space. LetТs move on and learn how we can use

XYZ values to define an objectТs transformation in addition to its size, shape, and

position.

An objectТs transformation describes an objectТs
position (translation),
orientation(rotation),
and
size
(scale) in 3D space.
When an object is first created(
когда объект первый раз создан ), its transformation is set to align with the global coordinates.

Its position(translation),  is set center to(устанавливаютс¤ в центре системе координат )   = {0,0,0},
its orientation(rotation,) is set  = {0,0,0},
and its size (scale)  is set to(
и размер(масштаб) установлен)  = {1,1,1}.
An objectТs transformation values are almost certain to change as you work with the object.

 

Translation

An objectТs translation describes its position in 3D space relative to its center and is

measured in defined grid units. LetТs take another look at the box we used in an earlier

example:

As you can see, the boxТs center is the same as the origin ({0,0,0}). What happens if you

want to move the box? You can move each one of the points, delete the existing box and

draw a new one in its new location, or simply translate the box. For example, setting a

Translate value of {2,2,2} would move boxТs lower left corner to {0,0,0} since (-2)+2=0.

Again, the Translate value refers to the location of the center of the object relative to world space.

 

 

Rotation

An objectТs rotation value refers to its orientation in 3D

space measured in degrees. As you probably know, any

actual object will revolve around its center of gravity

(balance point). Objects in Poser have no mass and no

center of gravity, so you can set the objectТs center

wherever you like and the object will rotate around that

point.

LetТs think back to the motorcycle example. If you model a motorcycle and decide you

wish to lean it 45 degrees, nothing is stopping you from performing trigonometric

calculations to determine the new location of each part. Remember that each part of the

motorcycle will move in at least two dimensions as the whole machine rotates. In this

case, since the motorcycle is rotating about the Z axis, you could simply enter a rotation

value of {0,0,45}. The trigonometric calculations will still need to be performed, however

Poser will get stuck with the job instead of you.

 

 

Scale

An objectТs scale value refers to its size in relation to itself and is measured in percent. In

this case, a value of 1 corresponds to 100%. Take the example of a circle. As with all other

Poser objects, it is initially created with a scale value of {1,1,1}, meaning that it is 100%

of its original size in all three dimensions.

Now that your perfect circle is in

place, you realize you need to

double its height on the Y axis.

Simply enter a scale value of

{1,2,1} and the circle will turn into

an ellipse that is twice as long on

the Y axis as it is wide. To stretch it

on the X axis, you would enter

{2,1,1}.

To compute every point on a model, multiply the original coordinates by the X, Y, and Z

components. With this in mind, it becomes easy to see how different values can change the

size of your object. For example, entering a scale value of {2,2,2} would double the

circleТs size. Poser allows you to set each scaling factor independently in order to obtain

squashing and stretching effects. This is called differential scaling.

 

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