Advanced text rendering
Flash Player 9 and later, Adobe AIR 1.0 and
ActionScript 3.0 provides a variety of classes in the flash.text
package to control the properties of displayed text, including embedded
fonts, anti-aliasing settings, alpha channel control, and other
specific settings. The ActionScript 3.0 Reference provides detailed
descriptions of these classes and properties, including the CSMSettings,
Font, and TextRenderer classes.
Using embedded fonts
When you specify a specific font for
a TextField in your application, Flash Player or AIR look for a
device font (a font that resides on the user’s computer) with the same
name. If it doesn’t find that font on the system, or if the user
has a slightly different version of a font with that name, the text
display could look very different from what you intend. By default,
the text appears in a Times Roman font.
To make sure the user sees exactly the right font, you can embed
that font in your application SWF file. Embedded fonts have a number
Embedded font characters are anti-aliased, making their
edges appear smoother, especially for larger text.
You can rotate text that uses embedded fonts.
Embedded font text can be made transparent or semitransparent.
You can use the kerning CSS style with embedded
The biggest limitation to using embedded fonts is that they increase
the file size or download size of your application.
The exact method of embedding a font file into your application
SWF file varies according to your development environment.
Once you have embedded a font you can make sure a TextField uses
the correct embedded font:
Set the embedFonts property of the TextField
Create a TextFormat object, set its fontFamily property
to the name of the embedded font, and apply the TextFormat object
to the TextField. When specifying an embedded font, the fontFamily property
should only contain a single name; it cannot use a comma-delimited
list of multiple font names.
If using CSS styles to set fonts for TextFields or components,
set the font-family CSS property to the name of
the embedded font. The font-family property must
contain a single name and not a list of names if you want to specify
an embedded font.
Embedding a font in Flash
Professional lets you embed almost any font you have installed on
your system, including TrueType fonts and Type 1 Postscript fonts.
You can embed fonts
in an application in many ways, including:
Setting the font and style properties of a TextField on the
Stage and clicking the Embed Fonts checkbox
Creating and referencing a font symbol
Creating and using a run-time shared library containing embedded
For more details about how to embed
fonts in applications, see “Embedded fonts for dynamic or input
text fields” in Using Flash.
Embedding a font in Flex
can embed fonts in a Flex application in many ways, including:
Using the [Embed] metadata tag in a script
Using the @font-face style declaration
Establish a class for the font and use the [Embed] tag
to embed it.
You can only embed TrueType fonts directly
in a Flex application. Fonts in other formats, such as Type 1 Postscript
fonts, can first be embedded in a SWF file using Flash Professional
and then that SWF file can be used in your Flex application. For more
details about using embedded fonts from SWF files in Flex, see “Embedding fonts
from SWF files” in Using Flex 4.
Controlling sharpness, thickness, and anti-aliasing
default, Flash Player or AIR determines the settings for text display
controls like sharpness, thickness, and anti-aliasing as text resizes,
changes color, or is displayed on various backgrounds. In some cases,
like when you have very small or very large text, or text on a variety
of unique backgrounds, you might want to maintain control over these
settings. You can override Flash Player or AIR settings using the flash.text.TextRenderer class
and its associated classes, like the CSMSettings class. These classes
give you precise control over the rendering quality of embedded
text. For more information about embedded fonts, see Using embedded fonts.
Note: The flash.text.TextField.antiAliasType
property must have the value AntiAliasType.ADVANCED in
order for you to set the sharpness, thickness, or the gridFitType
property, or to use the TextRenderer.setAdvancedAntiAliasingTable() method.
The following example applies custom continuous stroke modulation
(CSM) properties and formatting to displayed text using an embedded
font called myFont. When the user clicks the displayed
text, Flash Player or Adobe AIR applies the custom settings:
var format:TextFormat = new TextFormat();
format.color = 0x336699;
format.size = 48;
format.font = "myFont";
var myText:TextField = new TextField();
myText.embedFonts = true;
myText.autoSize = TextFieldAutoSize.LEFT;
myText.antiAliasType = AntiAliasType.ADVANCED;
myText.defaultTextFormat = format;
myText.selectable = false;
myText.mouseEnabled = true;
myText.text = "Hello World";
var myAntiAliasSettings = new CSMSettings(48, 0.8, -0.8);
var myAliasTable:Array = new Array(myAntiAliasSettings);
TextRenderer.setAdvancedAntiAliasingTable("myFont", FontStyle.ITALIC, TextColorType.DARK_COLOR, myAliasTable);