quadcurvetest.java

来自「纯java操作系统jnode,安装简单和操作简单的个人使用的Java操作系统」· Java 代码 · 共 71 行

/*
 * $Id: QuadCurveTest.java,v 1.3 2004/02/26 21:17:11 lsantha Exp $
 */
package org.jnode.test.gui;

import org.jnode.driver.video.util.Curves;

import java.awt.Color;
import java.awt.Component;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.geom.GeneralPath;

/**
 * @author epr
 */
public class QuadCurveTest {

    public static void main(String[] args)
            throws Exception {
        Frame wnd = new Frame();
        try {
            wnd.setSize(600, 400);
            wnd.add(new TestComponent());
            wnd.show();

            Thread.sleep(5000);

            wnd.hide();
        } finally {
            wnd.dispose();
        }
    }

    static class TestComponent extends Component {

        public void paint(Graphics g) {
            System.out.println("Paint called");
            paintComponent(g);
        }

        private void paintComponent(Graphics g) {
            final int w = getWidth();
            final int h = getHeight();
            g.setColor(Color.CYAN);
            final AffineTransform tx = new AffineTransform();
            tx.translate(50, h / 2);
            tx.scale(0.25, -0.25);
            final GeneralPath gp = new GeneralPath();
            gp.moveTo(w, 0);
            gp.quadTo(w, h, 0, h);
            gp.closePath();
            final Graphics2D g2d = (Graphics2D) g;
            g2d.draw(gp);
            g.setColor(Color.RED);
            drawQuadCurve(g, w, 0, w, h, 0, h);
        }

        protected void drawQuadCurve(Graphics g, double x0, double y0, double x1, double y1, double x2, double y2) {
            double[] points = new double[62];
            Curves.calculateQuadCurve(x0, y0, x1, y1, x2, y2, points);
            for (int i = 0; i < points.length - 2; i += 2) {
                g.drawLine((int) points[i], (int) points[i + 1], (int) points[i + 2], (int) points[i + 3]);
            }
        }

    }
}