ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with geometry
Defining the MatrixTransformer class
Flash Player 9 and later, Adobe AIR 1.0 and later
The MatrixTransformer class includes static methods that apply geometric transformations of Matrix objects.
The transform() method
The transform() method includes parameters for each of the following:
sourceMatrix—The input matrix, which the method transforms
xScale and yScale—The x and y scale factor
dx and dy—The x and y translation amounts, in pixels
rotation—The rotation amount, in degrees
skew—The skew factor, as a percentage
skewType—The direction in which the skew, either "right" or "left"
The return value is the resulting matrix.
The transform() method calls the following static methods of the class:
skew()
scale()
translate()
rotate()
Each returns the source matrix with the applied transformation.
The skew() method
The skew() method skews the matrix by adjusting the b and c properties of the matrix. An optional parameter, unit,
determines the units used to define the skew angle, and if necessary, the method converts the angle value to radians:
if (unit == "degrees")
{
angle = Math.PI * 2 * angle / 360;
}
if (unit == "gradients")
{
angle = Math.PI * 2 * angle / 100;
}
A skewMatrix Matrix object is created and adjusted to apply the skew transformation. Initially, it is the identity
matrix, as follows:
var skewMatrix:Matrix = new Matrix();
The skewSide parameter determines the side to which the skew is applied. If it is set to "right", the following code
sets the b property of the matrix:
skewMatrix.b = Math.tan(angle);
Otherwise, the bottom side is skewed by adjusting the c property of the Matrix, as follows:
skewMatrix.c = Math.tan(angle);
Last updated 6/6/2012
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