MACROMEDIA DIRECTOR MX-USING DIRECTOR MX, Руководство пользователя

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Chapter 5 182
When creating a bitmap mask for a sprite, use a grayscale palette if the mask cast member is an
8-bit (or less) image. An 8-bit mask affects only the transparency of the sprite and does not affect
the color. Director ignores the palette of mask cast members that are less than 32-bit images;
using a grayscale palette lets you view the mask in a meaningful way. If your mask cast member is
a 32-bit image, the colors of the mask tint the sprite’s colors.
If you do not need variable levels of opacity, use a 1-bit mask cast member to conserve memory
and disk space.
There are many ways to use Mask ink, but the following procedure explains the most basic
method.
To use Mask ink:
1
Decide which cast member you want to mask.
The cast member can be a bitmap of any depth.
2
In the next position in the same cast, create a duplicate of the cast member to serve as
the mask.
The mask cast member can actually be any image, but a duplicate of the original is usually the
most useful.
3
Edit the mask cast member in the Paint window or any image editor.
Black areas of the mask make the sprite completely opaque in those areas, and white areas
make it completely transparent (invisible).
4
Drag the original cast member to the Stage or Score to create a sprite.
5
Make sure the new sprite is selected, and select Mask ink from the Ink pop-up menu on the
Sprite tab in the Property inspector.
Only the parts of the sprite that are revealed by the mask are visible on the Stage.
About Darken and Lighten inks
Darken and Lighten inks provide a great control over a sprite’s RGB properties. You use them to
create color effects in sprites varying from subtle to surreal.
Darken and Lighten each change how Director applies the foreground and background color
properties of a sprite. Darken makes the background color equivalent to a color filter through
which the sprite is viewed on the Stage. Lighten tints the colors in a sprite lighter as the
background color gets darker. For both inks, the foreground color is added to the image to the
degree allowed by the other color control. Neither ink has any effect on a sprite until you change
the foreground or background color from the default settings of black and white.
Darken and Lighten are especially useful for animating unusual color effects. Because the
Foreground and Background color properties of the sprite control the effects, you can animate
color shifts to create dazzling effects without having to manually edit colors in a cast member. See
“Tweening other sprite properties” on page 188.