MACROMEDIA FIREWORKS MX 2004-USING FIREWORKS Use Manual page 137

By default, most bitmap masks are applied using their grayscale appearance, but you can also
apply them using their alpha channel. For more information, see
applied" on page
Note: Fireworks MX and Fireworks MX 2004 grayscale masks behave more like masks in other
graphics applications than masks in previous versions of Fireworks do. In grayscale masks created in
Fireworks MX and Fireworks MX 2004, white always reveals masked objects, and black always
hides masked objects. Compare this with Fireworks 4, where a black mask reveals underlying objects
and a white mask hides underlying objects.
Creating a mask from an existing object
You can create a mask from an existing object. When used as a mask, a vector object's path outline
can be used to clip or crop other objects. When a bitmap object is used as a mask, either the
brightness of its pixels or its transparency affects the visibility of other objects.
Masking objects using the Paste as Mask command
Using the Paste as Mask command, you can create masks by masking an object or group of
objects with another object. Paste as Mask creates either a vector mask or a bitmap mask. When
you use a vector object as the mask, Paste as Mask creates a vector mask that crops or clips masked
objects using the path outline of the vector object. When you use a bitmap image as the mask,
Paste as Mask creates a bitmap mask that affects the visibility of masked objects using the
grayscale color values of the bitmap object.
To create a mask with the Paste as Mask command:
Select the object you want to use as the mask. Shift-click to select multiple objects.
1
Note: If you use multiple objects as the mask, Fireworks always creates a vector mask, even if both
objects are bitmaps.
Position the selection so that it overlaps the object or group of objects to be masked.
2
The object or objects you want to use as the mask can be either in front of or behind the
objects or group to be masked.
Choose Edit > Cut to cut the object or objects you want to use as the mask.
3
149.
"Changing the way masks are
Masking images 137