带有字符 g.draw java 的轮廓形状

Question

所以基本上我需要制作带有星号的形状，如图所示：

所以这是我目前的解决方案。

import java.applet.Applet;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Stroke;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class ThreePointTen extends Applet{
    public void init(String[] a) {

  }

public void paint(Graphics g){
     char a = '*'; 
    //square
       g.drawString("**********", 25, 25);
       g.drawString("*              *", 25, 35);
       g.drawString("*              *", 25, 45);
       g.drawString("*              *", 25, 55);
       g.drawString("*              *", 25, 65);
       g.drawString("*              *", 25, 75);
       g.drawString("*              *", 25, 85);
       g.drawString("*              *", 25, 95);
       g.drawString("**********", 25, 105);

   //oval
       g.drawString("***", 175, 25);
       g.drawString("*         * ", 165, 35);
       g.drawString("*             * ", 158, 45);
       g.drawString("*             * ", 158, 55);
       g.drawString("*             * ", 158, 65);
       g.drawString("*             * ", 158, 75);
       g.drawString("*             * ", 158, 85);
       g.drawString("*         * ", 165, 95);
       g.drawString("***", 175, 105);

    }

}

我基本上只是在猜测如何制作每种形状以及它们的去向。这种方法极其缓慢且效率低下。我想知道是否可以使用 g.draw 制作一个形状，然后用一个字符来绘制它。

Answer 1

您可以创建一个内部由这些星号/星号组成的特殊Stroke。然后，您可以使用stroke.createStrokedShape(shape) 创建一个代表另一个形状的新形状，并使用此笔划绘制。

在http://www.jhlabs.com/java/java2d/strokes/ 有一个（Apache 许可的）这样的笔划实现（也包含在下面的代码中，带有链接和版权信息）

结果可能如下所示：

使用以下独立示例创建：

import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.font.FontRenderContext;
import java.awt.font.GlyphVector;
import java.awt.geom.AffineTransform;
import java.awt.geom.FlatteningPathIterator;
import java.awt.geom.GeneralPath;
import java.awt.geom.PathIterator;
import java.awt.geom.Rectangle2D;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class StarShapes
{
    public static void main(String[] args)
    {
        SwingUtilities.invokeLater(new Runnable()
        {
            @Override
            public void run()
            {
                createAndShowGUI();
            }
        });
    }

    private static void createAndShowGUI()
    {
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(new StarShapesPanel());
        f.setSize(600,400);
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

}

class StarShapesPanel extends JPanel
{
    @Override
    protected void paintComponent(Graphics gr)
    {
        super.paintComponent(gr);
        Graphics2D g = (Graphics2D)gr;
        g.setRenderingHint(
            RenderingHints.KEY_ANTIALIASING,
            RenderingHints.VALUE_ANTIALIAS_ON);

        Font starFont = new Font("Monospaced", Font.BOLD, 20);
        Shape starShape = createShape(starFont, "*");
        Stroke stroke = new ShapeStroke(new Shape[] { starShape }, 12.0f);

        Font textFont = new Font("Serif", Font.PLAIN, 250);
        Shape textShape = createShape(textFont,  "Stars!");
        g.translate(10,  250);
        Shape strokedTextShape = 
            stroke.createStrokedShape(textShape);
        g.fill(strokedTextShape);
    }

    private static Shape createShape(Font font, String s)
    {
        FontRenderContext fontRenderContext = 
            new FontRenderContext(null,true,true);
        GlyphVector glyphVector = 
            font.createGlyphVector(fontRenderContext, s);
        return glyphVector.getOutline();
    }

}



//============================================================================
// From http://www.jhlabs.com/java/java2d/strokes/

/*
Copyright 2006 Jerry Huxtable

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

class ShapeStroke implements Stroke {
    private Shape shapes[];
    private float advance;
    private boolean stretchToFit = false;
    private boolean repeat = true;
    private AffineTransform t = new AffineTransform();
    private static final float FLATNESS = 1;

    public ShapeStroke( Shape shapes, float advance ) {
        this( new Shape[] { shapes }, advance );
    }

    public ShapeStroke( Shape shapes[], float advance ) {
        this.advance = advance;
        this.shapes = new Shape[shapes.length];

        for ( int i = 0; i < this.shapes.length; i++ ) {
            Rectangle2D bounds = shapes[i].getBounds2D();
            t.setToTranslation( -bounds.getCenterX(), -bounds.getCenterY() );
            this.shapes[i] = t.createTransformedShape( shapes[i] );
        }
    }

    public Shape createStrokedShape( Shape shape ) {
        GeneralPath result = new GeneralPath();
        PathIterator it = new FlatteningPathIterator( shape.getPathIterator( null ), FLATNESS );
        float points[] = new float[6];
        float moveX = 0, moveY = 0;
        float lastX = 0, lastY = 0;
        float thisX = 0, thisY = 0;
        int type = 0;
        boolean first = false;
        float next = 0;
        int currentShape = 0;
        int length = shapes.length;

        float factor = 1;

        while ( currentShape < length && !it.isDone() ) {
            type = it.currentSegment( points );
            switch( type ){
            case PathIterator.SEG_MOVETO:
                moveX = lastX = points[0];
                moveY = lastY = points[1];
                result.moveTo( moveX, moveY );
                first = true;
                next = 0;
                break;

            case PathIterator.SEG_CLOSE:
                points[0] = moveX;
                points[1] = moveY;
                // Fall into....

            case PathIterator.SEG_LINETO:
                thisX = points[0];
                thisY = points[1];
                float dx = thisX-lastX;
                float dy = thisY-lastY;
                float distance = (float)Math.sqrt( dx*dx + dy*dy );
                if ( distance >= next ) {
                    float r = 1.0f/distance;
                    float angle = (float)Math.atan2( dy, dx );
                    while ( currentShape < length && distance >= next ) {
                        float x = lastX + next*dx*r;
                        float y = lastY + next*dy*r;
                        t.setToTranslation( x, y );
                        t.rotate( angle );
                        result.append( t.createTransformedShape( shapes[currentShape] ), false );
                        next += advance;
                        currentShape++;
                        if ( repeat )
                            currentShape %= length;
                    }
                }
                next -= distance;
                first = false;
                lastX = thisX;
                lastY = thisY;
                break;
            }
            it.next();
        }

        return result;
    }

}

Answer 2

对于基本实现，您需要创建要绘制的像素的“位图”。因此，您创建一个简单的形状图片，然后创建一个小算法来绘制形状中的每个“x”。

类似：

import java.awt.*;
import java.awt.event.*;
//import java.awt.image.*;
//import java.util.*;
import java.util.List;
import java.util.ArrayList;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
//import java.beans.*;
import javax.swing.border.*;
//import javax.swing.plaf.*;
//import javax.swing.text.*;
//import javax.swing.table.*;
//import java.io.*;
//import javax.imageio.*;
//import java.awt.geom.*;

public class PaintShape extends JPanel
{
    private final static String[] SQUARE =
    {
        "xxxxxxxxx",
        "x       x",
        "x       x",
        "x       x",
        "x       x",
        "x       x",
        "x       x",
        "x       x",
        "xxxxxxxxx"
    };

    private final static String[] ARROW =
    {
        "    x    ",
        "   xxx   ",
        "  xxxxx  ",
        "    x    ",
        "    x    ",
        "    x    ",
        "    x    ",
        "    x    ",
        "    x    "
    };

    private ArrayList<String[]> shapes = new ArrayList<String[]>();
    private String outlineCharacter = "*";

    public void addShape(String[] shape)
    {
        this.shapes.add( shape );
    }

    public void setOutlineCharacter(String outlineCharacter)
    {
        this.outlineCharacter = outlineCharacter;
    }

    @Override
    protected void paintComponent(Graphics g)
    {
        super.paintComponent(g);

        int outlineCharacterWidth = 10;
        int lineHeight = 10;

        int shapeStart = 0;
        int x = shapeStart;
        int y = 0;

        for (String[] shape: shapes)
        {
            y = lineHeight;

            for (int row = 0; row < shape.length; row++)
            {
                String bitmap = shape[row];

                x = shapeStart;

                for (int column = 0; column < bitmap.length(); column++)
                {
                    if (bitmap.charAt(column) == 'x')
                    {
                        g.drawString(outlineCharacter, x, y);
                    }

                    x += outlineCharacterWidth;
                }

                y += lineHeight;
            }

            x += 20; // gap between shapes
            shapeStart = x;
        }
    }

    private static void createAndShowGUI()
    {
        PaintShape paint = new PaintShape();
        paint.addShape(PaintShape.SQUARE);
        paint.addShape(PaintShape.ARROW);
        paint.addShape(PaintShape.SQUARE);

        JFrame frame = new JFrame("PaintShape");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(paint);
        frame.setLocationByPlatform( true );
        frame.setSize(200, 200);
        frame.setVisible( true );
    }

    public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                createAndShowGUI();
            }
        });
    }
}