Apple Shake 4 Tutorials - Manual (Page 147)

Tutorial 4 Working With Expressions 147
To link the node parameters:
1 In the RBlur1 parameters, expand the center parameter subtree, then type the following
in the xCenter field:
RGrad1.xCenter
2 Type the following in the yCenter field:
RGrad1.yCenter
These expressions are similar to rnd(time) or animVal * rndVal, except that they check
the xCenter and yCenter in the RGrad1 node for their values.
Note: If you enter new values for xCenter or yCenter, or drag the sliders for these
parameters, this breaks the links to RGrad1. You can restore the link by clicking Undo.
The origin point of the rays is now animated to match the center of the light.
Connecting the RBlur to the Composite
The following steps show you how to make all the node connections for the RBlur.
To connect the RBlur:
1 In Node View, select the Over2 node and press E to extract it from the script. Move it
down to make space for new nodes.
2 Select the RBlur1 node, and add a new Layer–lAdd node.
3 Rename the new lAdd1 node to Fog_Add.
4 Drag a connection from the Over1 node to the second input of Fog_Add.
5 Connect the output of Fog_Add to the first input of Over2.