Actionscript Cookbook

4.10. Filling a Shape with a Gradient

Problem

You want to draw a shape and fill it with a gradient at runtime.

Solution

Use the beginGradientFill( ) and endFill( ) methods to initiate and close a shape drawn at runtime.

Discussion

In a gradient fill, there is a graded change in colors. Flash supports linear gradients, in which one color fades into the next from left to right. Flash also supports radial gradients, in which the colors radiate out from a center point. You can initiate a gradient-filled shape using beginGradientFill( ) in the same way you initiate a solid-filled shape with beginFill( ). The difference is that the call to beginGradientFill( ) requires a more complex set of parameters:

gradientType

Either “linear” for a linear gradient, or “radial” for a radial gradient.

colors

An array of RGB values for the colors to use in the gradient. They are displayed in the gradient from left to right in a linear gradient, or from the center outward in a radial gradient.

alphas

An array of alpha values that correspond to the colors in the colors parameter array.

ratios

An array whose elements are numbers corresponding to the colors and alphas elements. The values in the ratios array indicate the point within the gradient at which each color is pure. The range of values for the ratios should be from 0 (leftmost point in a linear fill, or innermost point in a radial fill) to 255 (rightmost or outermost).

matrix

An object with the following properties:

matrixType

This value should ...