concat (Matrix.concat method) -- Flash CS3

Concatenates a matrix with the current matrix, effectively combining the geometric effects of the two. In mathematical terms, concatenating two matrixes is the same as combining them using matrix multiplication.

For example, if matrix m1 scales an object by a factor of four, and matrix m2 rotates an object by 1.5707963267949 radians (Math.PI/2), m1.concat(m2) transforms m1 into a matrix that scales an object by a factor of four and rotates the object by Math.PI/2 radians.

This method replaces the source matrix with the concatenated matrix. If you want to concatenate two matrixes without altering either of the two source matrixes, you can first copy the source matrix the clone() method, as shown in the Example section.

Parameters

Example

The following example creates three matrixes that define transformations for three rectangle movie clips. The first two matrixes rotate45Matrix and doubleScaleMatrix are applied to the two rectangles rectangleMc_1 and rectangleMc_2. Then the third matrix is created using the concat() method on rotate45Matrix and doubleScaleMatrix to create scaleAndRotateMatrix. This matrix is then applied to rectangleMc_3 to scale and rotate it.

import flash.geom.Matrix;
import flash.geom.Transform;

var rectangleMc_0:MovieClip = createRectangle(20, 80, 0x000000);
var rectangleMc_1:MovieClip = createRectangle(20, 80, 0xFF0000);
var rectangleMc_2:MovieClip = createRectangle(20, 80, 0x00FF00);
var rectangleMc_3:MovieClip = createRectangle(20, 80, 0x0000FF);

var rectangleTrans_1:Transform = new Transform(rectangleMc_1);
var rectangleTrans_2:Transform = new Transform(rectangleMc_2);
var rectangleTrans_3:Transform = new Transform(rectangleMc_3);

var rotate45Matrix:Matrix = new Matrix();
rotate45Matrix.rotate(Math.PI/4);
rectangleTrans_1.matrix = rotate45Matrix;
rectangleMc_1._x = 100;
trace(rotate45Matrix.toString()); // (a=0.707106781186548, b=0.707106781186547, c=-0.707106781186547, d=0.707106781186548, tx=0, ty=0)

var doubleScaleMatrix:Matrix = new Matrix();
doubleScaleMatrix.scale(2, 2);
rectangleTrans_2.matrix = doubleScaleMatrix;
rectangleMc_2._x = 200;
trace(doubleScaleMatrix.toString()); // (a=2, b=0, c=0, d=2, tx=0, ty=0)

var scaleAndRotateMatrix:Matrix = doubleScaleMatrix.clone();
scaleAndRotateMatrix.concat(rotate45Matrix);
rectangleTrans_3.matrix = scaleAndRotateMatrix;
rectangleMc_3._x = 300;
trace(scaleAndRotateMatrix.toString()); // (a=1.4142135623731, b=1.41421356237309, c=-1.41421356237309, d=1.4142135623731, tx=0, ty=0)

function createRectangle(width:Number, height:Number, color:Number):MovieClip {
    var depth:Number = this.getNextHighestDepth();
    var mc:MovieClip = this.createEmptyMovieClip("mc_" + depth, depth);
    mc.beginFill(color);
    mc.lineTo(0, height);
    mc.lineTo(width, height);
    mc.lineTo(width, 0);
    mc.lineTo(0, 0);
    return mc;
}