Apple Shake 4 - Manual (Page 465)

Chapter 16 Compositing With Layer Nodes 465
channel
Lets you pick the channel from the third image that you want to use as the mask. You
can pick the r, g, b, or a channel.
mixPercent
The percentage of the second image that’s mixed in.
invert
Inverts the mask created from the third image.
LayerX
The LayerX node is exactly like ColorX, except that you also have access to a second
image. This allows you to composite with expressions. The values of the second image
are accessed with the variables r2, g2, b2, a2, and z2. For more information, see “
ColorX ”
on page 647.
Parameters
This node displays the following control in the Parameters tab:
r, g, b, a, and zExpr
Each parameter allows you to enter a separate expression specific to that channel. By
default, the parameters default to r, g, b, a, and z.
Max
The Max node compares two images and takes the pixel with the higher value. This is a
good tool to merge alpha masks.
Parameters
This node displays the following controls in the Parameters tab:
clipMode
Toggles between the foreground (0) or the background (1) image to set the output
resolution.
percent
A gain on the second image, which is effectively the same as a brightness node applied
to the second image.
Min
The Min node compares two images and takes the pixel with the lower value. Like the
Max node, this is a good tool to merge alpha masks.
Parameters
This node displays the following controls in the Parameters tab: