2008

U Trail Adds “direction” to your blur by weighting more blur to either side
of the U axis. This adds a streaking effect and creates the illusion that your
objects or your camera are rapidly moving in a particular direction.
V Pixel Radius Determines the vertical intensity of the Blur effect. Increasing
the value increases the number of surrounding pixels that each pixel will use
to compute its blur, and creates a greater vertical blur for the image.
V Trail Adds “direction” to your blur by weighting more blur to either side
of the V axis. This adds a streaking effect and creates the illusion that your
objects or your camera are rapidly moving in a particular direction.
Rotation Rotates the axis of the U and V pixels that will be blurred by the
U and V Pixel Radius spinners. By using Rotation with the U and V Pixel Radius
spinners you can have the Blur effect applied to any direction in your rendered
image. When rotation is 0, U corresponds to the image’s X axis and V
corresponds to the image’s Y axis.
Affect Alpha Applies the Directional Blur effect to the Alpha channel when
turned on.
Radial Applies the Blur effect radially. Using the Radial parameters you can
define a point within your rendered image to use as the center of the Radial
Blur. You can use an object as the center or an arbitrary location set by the X
and Y Origin spinners. The Blur effect will apply the least amount of blur to
the center origin of the effect and gradually increase the blur to the pixels
further away from the center. This can be used to simulate motion blur caused
by camera zoom.
Pixel Radius Determines the intensity of the Radius Blur effect. Increasing
the value increases the number of surrounding pixels that each pixel will use
to compute its blur. The more pixels used means a greater blur for the image.
Trail Adds “direction” to your blur by weighting more or less blur toward
the center of the Blur effect. This adds a streaking effect and creates the illusion
that your objects or your camera are rapidly moving in a particular direction.
X/Y Origin Specifies the center of the blur, in pixels, with respect to the
dimensions of the rendered output.
None Lets you specify an object whose center serves as the center of the blur
effect. Click this, select an object, and then turn on Use Object Center. The
object name appears on the button.
Clear Removes the object name from the button above.
Use Object Center When on, the object specified by the None button (tooltip:
Pick an object to center on.) serves as the center of the blur effect. If no object
6464 | Chapter 19 Effects and Environments