ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Using the drawing API
The easiest way to define the matrix is by using the Matrix class’s createGradientBox() method, which creates a
matrix that is used to define the gradient. You define the scale, rotation, and position of the gradient using the
parameters passed to the createGradientBox() method. The createGradientBox() method accepts the following
parameters:
Gradient box width: the width (in pixels) to which the gradient will spread
Gradient box height: the height (in pixels) to which the gradient will spread
Gradient box rotation: the rotation (in radians) that will be applied to the gradient
Horizontal translation: how far (in pixels) the gradient is shifted horizontally
Vertical translation: how far (in pixels) the gradient is shifted vertically
For example, consider a gradient with the following characteristics:
GradientType.LINEAR
Two colors, green and blue, with the ratios array set to [0, 255]
SpreadMethod.PAD
InterpolationMethod.LINEAR_RGB
The following examples show gradients in which the rotation parameter of the createGradientBox() method
differs as indicated, but all other settings stay the same:
width = 100;
height = 100;
rotation = 0;
tx = 0;
ty = 0;
width = 100;
height = 100;
rotation = Math.PI/4; // 45°
tx = 0;
ty = 0;
width = 100;
height = 100;
rotation = Math.PI/2; // 90°
tx = 0;
ty = 0;
The following examples show the effects on a green-to-blue linear gradient in which the rotation, tx, and ty
parameters of the createGradientBox() method differ as indicated, but all other settings stay the same:
Last updated 6/6/2012
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