当鼠标快速移动时,有谁知道如何绘制实线?
当我慢慢移动鼠标时,线条被绘制为实线,但是当鼠标快速移动时,线条就像虚线一样绘制,如此处所示.
绘制线条的代码目前是这样的:
private final class MouseL extends MouseAdapter implements MouseMotionListener
{
@Override
public void mouseClicked(MouseEvent e)
{
Point p = e.getPoint();
int half = brushDiameter / 1200;
Graphics2D g = getImage().createGraphics();
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.setPaint(getColor());
g.fillOval(p.x - half, p.y - half, brushDiameter, brushDiameter);
g.dispose();
repaint(p.x - half, p.y - half, brushDiameter, brushDiameter);
}
@Override
public void mouseDragged(MouseEvent e)
{
mouseClicked(e);
}
但我想改变它,使线看起来很稳固.非常感谢任何有助于实现这一目标的帮助.
解决方法:
简单:如果要绘制曲线,请不要绘制单个点或椭圆.而是使用g.drawLine(…)将相邻点连接起来.如果想要更粗的曲线,请更改Graphics2D的笔划宽度.
例如:
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Stroke;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
@SuppressWarnings("serial")
public class DrawCurve extends JPanel {
private static final int PREF_W = 600;
private static final int PREF_H = PREF_W;
private static final Color CURRENT_PTS_COLOR = Color.BLUE.brighter().brighter();
public static final Color IMG_COLOR = Color.RED;
public static final Stroke IMG_STROKE = new BasicStroke(4f);
private static final Color FILL_COLOR = Color.WHITE;
private BufferedImage img = null;
private List<Point> currentPts = new ArrayList<>();
public DrawCurve() {
img = new BufferedImage(PREF_W, PREF_H, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setBackground(FILL_COLOR);
g2.clearRect(0, 0, PREF_W, PREF_H);
g2.dispose();
MyMouse myMouse = new MyMouse();
addMouseListener(myMouse);
addMouseMotionListener(myMouse);
}
@Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (img != null) {
g.drawImage(img, 0, 0, null);
}
Graphics2D g2 = (Graphics2D) g;
g2.setColor(CURRENT_PTS_COLOR);
for (int i = 1; i < currentPts.size(); i++) {
int x1 = currentPts.get(i - 1).x;
int y1 = currentPts.get(i - 1).y;
int x2 = currentPts.get(i).x;
int y2 = currentPts.get(i).y;
g2.drawLine(x1, y1, x2, y2);
}
}
private class MyMouse extends MouseAdapter {
@Override
public void mousePressed(MouseEvent e) {
currentPts = new ArrayList<>();
currentPts.add(e.getPoint());
repaint();
}
@Override
public void mouseDragged(MouseEvent e) {
currentPts.add(e.getPoint());
repaint();
}
@Override
public void mouseReleased(MouseEvent e) {
currentPts.add(e.getPoint());
Graphics2D g2 = img.createGraphics();
g2.setColor(IMG_COLOR);
g2.setStroke(IMG_STROKE);
for (int i = 1; i < currentPts.size(); i++) {
int x1 = currentPts.get(i - 1).x;
int y1 = currentPts.get(i - 1).y;
int x2 = currentPts.get(i).x;
int y2 = currentPts.get(i).y;
g2.drawLine(x1, y1, x2, y2);
}
g2.dispose();
currentPts.clear();
repaint();
}
}
private static void createAndShowGui() {
JFrame frame = new JFrame("DrawCurve");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new DrawCurve());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}