actionscript-3 - AS3如何扩宽声波？

Question

我正在实现这个代码来绘制声波。它位于 soundmixer 的 adobe livedocs 中.我的问题是如何扩大声波？例如，我希望它是 655 像素。我可以将其更改为绘制到不同的 channel ，也可以更改绘图的高度，但找不到如何更改整个绘图的宽度

知道怎么做吗？

谢谢。

  package {
     import flash.display.Sprite;
     import flash.display.Graphics;
     import flash.events.Event;
     import flash.media.Sound;
     import flash.media.SoundChannel;
      import flash.media.SoundMixer;
     import flash.net.URLRequest;
      import flash.utils.ByteArray;
     import flash.text.TextField;

    public class SoundMixer_computeSpectrumExample extends Sprite {

        public function SoundMixer_computeSpectrumExample() {
           var snd:Sound = new Sound();
           var req:URLRequest = new URLRequest("Song1.mp3");
           snd.load(req);

           var channel:SoundChannel;
           channel = snd.play();
           addEventListener(Event.ENTER_FRAME, onEnterFrame);
           channel.addEventListener(Event.SOUND_COMPLETE, onPlaybackComplete);
        }

       private function onEnterFrame(event:Event):void {
           var bytes:ByteArray = new ByteArray();
           const PLOT_HEIGHT:int = 25;
           const CHANNEL_LENGTH:int = 256;

           SoundMixer.computeSpectrum(bytes, false, 0);

           var g:Graphics = this.graphics;

           g.clear();

           g.lineStyle(0, 0x6600CC);
           g.beginFill(0x6600CC);
            g.moveTo(0, PLOT_HEIGHT);

           var n:Number = 0;

           for (var i:int = 0; i < CHANNEL_LENGTH; i++) {
               n = (bytes.readFloat() * PLOT_HEIGHT);
               g.lineTo(i * 2, PLOT_HEIGHT - n);
           }

           g.lineTo(CHANNEL_LENGTH * 2, PLOT_HEIGHT);
           g.endFill();

           g.lineStyle(0, 0xCC0066);
           g.beginFill(0xCC0066, 0.5);
           g.moveTo(CHANNEL_LENGTH * 2, PLOT_HEIGHT);

           for (i = CHANNEL_LENGTH; i > 0; i--) {
               n = (bytes.readFloat() * PLOT_HEIGHT);
               g.lineTo(i * 2, PLOT_HEIGHT - n);
           }

           g.lineTo(0, PLOT_HEIGHT);
           g.endFill();
        }

         private function onPlaybackComplete(event:Event):void {
             removeEventListener(Event.ENTER_FRAME, onEnterFrame);
        }
     }
 }

Answer 1

更改 lineTo(x,y) 调用中的 x 因子。

例如，更改:

g.lineTo(i * 2, PLOT_HEIGHT - n);

类似于:

var xfactor:Number = 655/256;
g.lineTo(i * xfactor, PLOT_HEIGHT - n);

由于 xfactor 是固定的，请在进入循环之前计算它(不在循环内(