arcedtextlabel.java

一个很好的java2d小程序的源码

package wt;
// Decompiled by Jad v1.5.8e. Copyright 2001 Pavel Kouznetsov.
// Jad home page: http://www.geocities.com/kpdus/jad.html
// Decompiler options: packimports(3) 
// Source File Name:   ArcedTextLabel.java

import java.awt.geom.AffineTransform;

class ArcedTextLabel extends TransformedTextLabel
{

    public ArcedTextLabel()
    {
    }

    public ArcedTextLabel(double spread, double rise)
    {
        this();
        setSpreadAndRise(spread, rise);
    }

    public void setSpreadAndRise(double spread, double rise)
    {
        double width = spread / 2D;
        if(rise > 0.0D)
        {
            mRadius = ((width * width) / rise + rise) / 2D;
            mAngle = 2D * Math.atan2(width, mRadius - rise);
        } else
        {
            mRadius = spread;
            mAngle = 0.0D;
        }
        invalidateTransforms();
    }

    public AffineTransform computeTransform(int i)
    {
        int n = length();
        double w0 = getCharDist(0);
        double wn = getTextDist() - getCharDist(length() - 1);
        double pos = n < 2 ? 0.5D : (getCharDist(i) - w0) / (getTextDist() - w0 - wn);
        if(mAngle > 0.0D)
        {
            double t0 = w0 / mRadius;
            double tn = wn / mRadius;
            double angle = ((mAngle - t0 - tn) * pos - mAngle / 2D) + t0;
            return AffineTransform.getRotateInstance(angle, 0.0D, mRadius);
        } else
        {
            double dist = ((mRadius - w0 - wn) * pos - mRadius / 2D) + w0;
            return AffineTransform.getTranslateInstance(dist, 0.0D);
        }
    }

    private double mRadius;
    private double mAngle;
}