Adobe 38039927 User Guide - Page 171

ADOBE FIREWORKS CS3 166 User Guide Bitmap mask properties in the Property inspector when a bitmap tool is selected 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 "Changing the way masks are applied" on page 176. 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: 1 Select the object you want to use as the mask. Shift-click to select multiple objects. Note: If you use multiple objects as the mask, Fireworks always creates a vector mask, even if both objects are bitmaps. 2 Position the selection so that it overlaps the object or group of objects to be masked. 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. 3 Select Edit > Cut to cut the object or objects you want to use as the mask. 4 Select the object or group you want to mask.