Controlling the scale,
transformation or rotation (SRT) of an object with ICE isn't any different from
doing the same when dealing with point or "particles". The thing you need to keep in
mind though is how you set the data. While you can read any of the SRT
properties of an object you can't set the individual X,Y or Z transforms
directly nor their local transform values. In order to set any of the transform
values you need to set the whole global transform matrix. Note that this is merely
a structural thing and does not affect what you can and cannot do with an
object’s SRT.

01 Creating the scene

Get a Sphere
(From the Get > Primitive > Polygon Mesh menu) and a Null object (From
the Get > Primitive menu). The null object serves as a place holder for your
ICE Tree. Select the Null object and press [Alt] + [9] to open an ICE Tree
view. Get a Get Data node, open its PPG and
enter sphere.kine.global as the Reference. In order to change the
individual components of the SRT matrix you first need to deconstruct the
matrix, make the modifications to the respective components, and then put the
matrix back together. Get a
Matrix to SRT node and connect the Value output of the sphere.kine.global node
to its Matrix input. Get a SRT to Matrix node and connect the Scaling and
Translation output of the Matrix to SRT to its corresponding input.

**02 Deconstructing the Matrix**

Get a 3D Vector
to Scalar node and connect the Translation output of the Matrix to SRT to its
Vector input. Get a 3D Vector node, a Turbulence node and a Multiply node.
Connect the 3D Vector to the Position input of the Turbulence node and the
Turbulence to the Value1 input of the Multiply node. Get a Add node and connect
the Y output of the 3D Vector to Scalar to its Value1 input. Connect the
Multiply node to the Value2 input of the Add node. Open the Turbulence PPG and
lower the Time Frequency to 0.5 or so. This will control the speed of the
turbulence. The Multiply node controls the strength of the turbulence. Open the
PPG and set the Value2 to 20

03 Put the Matrix back together.

By using the
Add node, the turbulence will be added on top of the Sphere's Y translation
rather than completely replacing it. Get a Scalar to 3D Vector and connect the
X and Z output of the 3D Vector to Scalar node to its corresponding inputs.
Connect the Result output of the Add node to the Y input. Connect the Vector
output of the Scalar to 3D Vector node to the Translation input of the SRT to
Matrix node. Get a Set Data node, open its PPG and enter sphere.kine.global as
the reference. Connect the Matrix output of the SRT to Matrix node to the sphere.kine.global
input of the Set Data node. Connect the Execute output of the Set Data node to
the port1 of the ICETree node.

The project files used in this tutorial can be found at:http://dl.dropbox.com/u/3834689/CaffeineAbuse/ICE_Kinematic_Turbulence.zip

The project files used in this tutorial can be found at:http://dl.dropbox.com/u/3834689/CaffeineAbuse/ICE_Kinematic_Turbulence.zip

## 1 comments:

You completely duplication our mean and the difference of our information.

all vectors

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