Java: ToyGraphics

/*
 * Copyright (c) 2020 Yoshihisa Nitta
 * Released under the MIT license
 * http://opensource.org/licenses/mit-license.php
 */
import java.util.*;
import java.awt.geom.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;

public class ToyGraphics extends JComponent {
    int width, height;
    BufferedImage image;
    protected Graphics2D g2d;
    public boolean isMousePressed = false;
    public void initImage(int w,int h) {
	width = w;
	height = h;
	image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
	g2d = image.createGraphics();
	setFont();
	clear();
    }
    public void initFrame() {
	JFrame frame = new JFrame("Graphic Window");
	Container c = frame.getContentPane();
	Dimension size = getPreferredSize();
	int w = size.width;
	int h = size.height;
	c.setSize(w,h);
	c.add(this,BorderLayout.CENTER);
	frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	frame.pack();
	frame.setVisible(true);
    }
    public Dimension getPreferredSize() {
	return new Dimension(image.getWidth(),image.getHeight());
    }
    public ToyGraphics() { this(1280,720); }
    public ToyGraphics(int w,int h) {
	initImage(w,h);
	initFrame();
    }
    public void setFont() { setFont("Serif",24); }
    public void setFont(String name,int size) {
	g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
			     RenderingHints.VALUE_ANTIALIAS_ON);
	Font font = new Font(name,Font.PLAIN,size);
	g2d.setFont(font);
    }
    public void setColor(Color col) { g2d.setColor(col); }
    public void drawText(String txt,int x,int y) {
	g2d.drawString(txt,x,y);
    }
    public void paint(Graphics g) {
	g.drawImage(image,0,0,this);
    }
    public static int rgb2pixel(int r,int g,int b)
	throws IllegalArgumentException {
	return rgb2pixel(255,r,g,b);
    }
    public static int rgb2pixel(int a,int r,int g,int b)
	throws IllegalArgumentException {
	if (a<0 || a>255 || r<0 || r>255 || g<0 || g>255 || b<0 || b>255)
	    throw new IllegalArgumentException("bad color:("+a+","+r+","+g+","+b+")");
	return (a<<24) | (r << 16) | (g << 8) | (b);
    }
    public void drawRGB(int x,int y,int r,int g,int b) {
	setRGB(x,y,r,g,b);
	repaint(x,y,1,1);
    }
    public void drawRGB(int x,int y,int pxl) {
	setRGB(x,y,pxl);
	repaint(x,y,1,1);
    }
    public void setRGB(int x,int y,int r,int g,int b) {
	setRGB(x,y,rgb2pixel(r,g,b));
    }
    public void setRGB(int x,int y,int pxl) {
	if (x < 0 || x>width || y<0 || y>height) return;
	image.setRGB(x,y,pxl);
    }
    public void clear() {
	for (int y=0; y<height; y++) {
	    for (int x=0; x<width; x++) {
		setRGB(x,y,0,0,0);
	    }
	}
    }
    private void fillRandomColor(Random random) {
	for (int y=0; y<height; y++) {
	    for (int x=0; x<width; x++) {
		int pxl = random.nextInt() | 0xff000000;
		setRGB(x,y,pxl);
	    }
	}
    }
}

import java.awt.*;
import java.awt.geom.*;

public class Sample1 {
    public void run() {
	ToyGraphics tg = new ToyGraphics(640, 360); // 640x360のサイズのウィンドウを生成する
	
	tg.g2d.setPaint(Color.black);
	tg.g2d.fill(new Rectangle2D.Double(0, 0, tg.width, tg.height));  // ウィンドウ全体を黒で塗りつぶす

	tg.g2d.setStroke(new BasicStroke(3.0f)); // 描画する線の太さを3.0fにする。

	tg.g2d.setPaint(Color.white);
	tg.g2d.draw(new Line2D.Double(20,20,100,80));   // 白色の線分を描画する

	tg.g2d.setPaint(Color.cyan);
	tg.g2d.draw(new Rectangle2D.Double(50,50,200,100));   // 水色の長方形(枠)を描画する

	tg.g2d.setPaint(Color.blue);
	tg.g2d.fill(new Rectangle2D.Double(100,100,300,100));  // 青色の長方形(塗りつぶし)を描画する

	tg.g2d.setStroke(new BasicStroke(3.0f)); // 枠線の太さを5.0fに変更する
	tg.g2d.setPaint(Color.red);
	tg.g2d.draw(new Arc2D.Double(150,150,200,100,0,360,Arc2D.OPEN));  // 赤色の楕円(枠)を描画する

	tg.g2d.setPaint(Color.yellow);
	tg.g2d.fill(new Arc2D.Double(200,220,300,100,0,360,Arc2D.OPEN));  // 黄色の楕円(塗りつぶし)を描画する

	tg.g2d.setPaint(Color.green);
	tg.g2d.drawString("Hello World", 150, 80);   // 緑の文字を描画する

	tg.repaint(0,0,tg.width,tg.height); // 範囲を指定して再描画する (これが無いと変更が反映されない)
    }
    public static void main(String[] args) {
	Sample1 app = new Sample1();
	app.run();
    }
}

import java.awt.*;
import java.awt.geom.*;

public class Sample2 extends ToyGraphics {
    public Sample2() { super(640, 360); }
    public void run() {
	g2d.setPaint(Color.black);
	g2d.fill(new Rectangle2D.Double(0, 0, width, height));  // ウィンドウ全体を黒で塗りつぶす

	g2d.setStroke(new BasicStroke(3.0f)); // 描画する線の太さを3.0fにする。

	g2d.setPaint(Color.white);
	g2d.draw(new Line2D.Double(20,20,100,80));   // 白色の線分を描画する

	g2d.setPaint(Color.cyan);
	g2d.draw(new Rectangle2D.Double(50,50,200,100));   // 水色の長方形(枠)を描画する

	g2d.setPaint(Color.blue);
	g2d.fill(new Rectangle2D.Double(100,100,300,100));  // 青色の長方形(塗りつぶし)を描画する

	g2d.setStroke(new BasicStroke(3.0f)); // 枠線の太さを5.0fに変更する
	g2d.setPaint(Color.red);
	g2d.draw(new Arc2D.Double(150,150,200,100,0,360,Arc2D.OPEN));  // 赤色の楕円(枠)を描画する

	g2d.setPaint(Color.yellow);
	g2d.fill(new Arc2D.Double(200,220,300,100,0,360,Arc2D.OPEN));  // 黄色の楕円(塗りつぶし)を描画する

	g2d.setPaint(Color.green);
	g2d.drawString("Hello World", 150, 80);   // 緑の文字を描画する

	repaint(0,0,width,height); // 範囲を指定して再描画する (これが無いと変更が反映されない)
    }
    public static void main(String[] args) {
	Sample2 app = new Sample2();
	app.run();
    }
}

import java.awt.*;
import java.awt.geom.*;

public class Sample3 extends ToyGraphics {
    public Sample3() { super(640, 360); }
    public void run() {
	g2d.setPaint(Color.black);
	g2d.fill(new Rectangle2D.Double(0, 0, width, height));  // ウィンドウ全体を黒で塗りつぶす

	drawRect(50,50,200,100,255,0,0);
	drawRect(100,80,200,100,0,255,255);
    }
    void drawRect(int x,int y,int w,int h,int r,int g,int b) {
	for (int line=y; line < y+h; line++) {
	    for (int col=x; col < x+w; col++) {
		setRGB(col,line,r,g,b);
	    }
	}
	repaint(x,y,w,h);
    }
    public static void main(String[] args) {
	Sample3 app = new Sample3();
	app.run();
    }
}

import java.awt.*;
import java.awt.geom.*;
import java.awt.event.*;

public class Sample4 extends ToyGraphics implements MouseListener {
    public Sample4() { super(640,480); }
    public void run() {
	addMouseListener(this);  // ウィンドウに対するMouseイベントを自分で受け取る
	g2d.setPaint(Color.white);
	g2d.fill(new Rectangle2D.Double(0, 0, width, height));  // ウィンドウ全体を黒で塗りつぶす
	repaint(0,0,width,height); // 範囲を指定して再描画する (これが無いと変更が反映されない)
    }
    public void mouseClicked(MouseEvent e) { System.err.println("mouseClicked"); }
    public void mousePressed(MouseEvent e) {
	int mx = e.getX(), my = e.getY();
	System.err.println("mousePressed " + mx + " " + my);
	int w=10, h=10, x=mx-w/2, y=my-h/2;
	g2d.setPaint(Color.blue);
	g2d.fill(new Rectangle2D.Double(x,y,w,h));  // (x,y)の回りを10x10の青色の四角で塗りつぶす
	repaint(x,y,w,h);
    }
    public void mouseReleased(MouseEvent e) {
	int mx = e.getX(), my = e.getY();
	System.err.println("mouseReleased " + mx + " " + my);
	int w=10, h=10, x=mx-w/2, y=my-h/2;
	g2d.setPaint(Color.red);
	g2d.fill(new Rectangle2D.Double(x,y,w,h));  // (x,y)の回りを10x10の赤色の四角で塗りつぶす
	repaint(x,y,w,h);
    }
    public void mouseEntered(MouseEvent e) { System.err.println("mouseEntered"); }
    public void mouseExited(MouseEvent e) { System.err.println("mouseExited"); }


    public static void main(String[] args) {
	Sample4 app = new Sample4();
	app.run();
    }
}

% java Sample3      
mouseEntered
mousePressed 104 83
mouseReleased 192 170
mousePressed 276 201
mouseReleased 236 295
mousePressed 394 395
mouseReleased 397 227

import java.util.*;
import java.awt.*;
import java.awt.geom.*;
import java.awt.event.*;

public class WinDraw extends ToyGraphics implements MouseListener {
    static final int RECTANGLE = 1;
    static final int CIRCLE = 2;

    boolean isDragging = false;
    int sx, sy, ex, ey; // Mouse pressed (sx,sy), released (ex,ey)
    Color strokeColor = Color.red;
    int shapeType = RECTANGLE;

    int[][] menuArea = {
	{0,0,100,30},
	{0,30,100,30},
	{0,60,100,30},
	{0,90,100,30},
	{0,120,100,30},
    };
    String[] menuString = { "Redraw", "Red", "Blue", "Rectangle", "Circle" };
    ArrayList<Shape> shapes;
    public WinDraw() { this(1280,720); }
    public WinDraw(int w,int h) {
	shapes = new ArrayList<Shape>();
	addMouseListener(this);
    }
    public void run() {
	redraw();
    }
    boolean inArea(int mx,int my,int x,int y,int w,int h) {
	return (mx >= x && mx < x+w && my >= y && my < y+h);
    }
    boolean inArea(int mx,int my,int[] r) {
	int x=r[0], y=r[1], w=r[2], h=r[3];
	return (mx >= x && mx < x+w && my >= y && my < y+h);
    }
    boolean checkMenu(int sx,int sy) {
	for (int i = 0; i<menuArea.length; i++) {
	    int[] r= menuArea[i];
	    if (inArea(sx,sy,r)) {
		System.err.println("menu "+i);
		switch (i) {
		case 0: redraw(); break;
		case 1: strokeColor = Color.red; break;
		case 2: strokeColor = Color.blue; break;
		case 3: shapeType = RECTANGLE; break;
		case 4: shapeType = CIRCLE; break;
		default: System.err.println("no menu"); System.exit(-1);break;
		}
		return true;
	    }
	}
	return false;
    }
    void redraw() {
	g2d.setPaint(Color.black);
	g2d.fill(new Rectangle2D.Double(0,0,width,height));
	drawMenu();
	for (Shape shape: shapes) { shape.draw(g2d); }
	repaint(0,0,width,height);
    }
    void drawMenu() {
	for (int i=0; i<menuArea.length; i++) {
	    int[] r = menuArea[i];
	    Rectangle2D shape = new Rectangle2D.Double(r[0],r[1],r[2],r[3]);
	    g2d.setPaint(Color.white);
	    g2d.fill(shape);
	    g2d.setPaint(Color.black);
	    g2d.draw(shape);
	    g2d.drawString(menuString[i], r[0]+5, r[1]+20);
	    repaint(r[0],r[1],r[2],r[3]);
	}
    }
    public void mouseClicked(MouseEvent e) {}
    public void mousePressed(MouseEvent e) {
	sx = e.getX(); sy = e.getY();
	System.err.println("Pressed " + sx + " " + sy);
	isDragging = !checkMenu(sx,sy);
    }
    public void mouseReleased(MouseEvent e) {
	ex = e.getX();
	ey = e.getY();
	System.err.println("Released " + ex + " " + ey);
	if (! isDragging) return; // select menu
	int x = Math.min(sx,ex), y = Math.min(sy,ey), w = Math.abs(ex-sx), h = Math.abs(ey-sy);
	Shape shape;
	if (shapeType == RECTANGLE) {
	    shape = new Rect(x,y,w,h,3,strokeColor,null);
	} else {  // (shapeType == CIRCLE) 
	    shape = new Circle(x,y,w,h,3,strokeColor,null);
	}
	shape.draw(g2d);
	repaint(x,y,w,h);
	shapes.add(shape);
    }
    public void mouseEntered(MouseEvent e) {}
    public void mouseExited(MouseEvent e) {}

    public static void main(String[] args) {
	WinDraw wd = new WinDraw();
	wd.run();
    }
}

import java.awt.*;

public abstract class Shape {
    int x, y;
    Color strokeColor, fillColor;
    abstract void draw(Graphics2D g2d);
}

import java.awt.*;
import java.awt.geom.*;

public class Rect extends Shape {
    int w, h, lineWidth;
    public Rect(int x,int y,int w,int h,int lineWidth,Color strokeColor,Color fillColor) {
	this.x = x; this.y = y; this.w = w; this.h = h; this.lineWidth = lineWidth;
	this.strokeColor = strokeColor; this.fillColor = fillColor;
    }
    void draw(Graphics2D g2d) {
	Rectangle2D shape = new Rectangle2D.Double(x,y,w,h);
	if (fillColor != null) {
	    g2d.setPaint(fillColor);
	    g2d.fill(shape);
	}
	if (strokeColor != null) {
	    g2d.setStroke(new BasicStroke((float) lineWidth));
	    g2d.setPaint(strokeColor);
	    g2d.draw(shape);
	}
    }
}

import java.awt.*;
import java.awt.geom.*;

public class Circle extends Shape {
    int w, h, lineWidth;
    public Circle(int x,int y,int w,int h,int lineWidth,Color strokeColor,Color fillColor) {
	this.x = x; this.y = y; this.w = w; this.h = h; this.lineWidth = lineWidth;
	this.strokeColor = strokeColor; this.fillColor = fillColor;
    }
    void draw(Graphics2D g2d) {
	Arc2D shape = new Arc2D.Double(x,y,w,h,0,360,Arc2D.OPEN);
	if (fillColor != null) {
	    g2d.setPaint(fillColor);
	    g2d.fill(shape);
	}
	if (strokeColor != null) {
	    g2d.setStroke(new BasicStroke((float) lineWidth));
	    g2d.setPaint(strokeColor);
	    g2d.draw(shape);
	}
    }
}

% javac WinDraw.java
% java WinDraw
Pressed 11 46
menu 1
Released 11 46
Pressed 65 103
menu 3
Released 65 103
Pressed 251 163
Released 430 315
Pressed 54 131
menu 4
Released 56 132
Pressed 683 272
Released 967 479
Pressed 30 74
menu 2
Released 31 74
Pressed 372 120
Released 683 382
Pressed 73 109
menu 3
Released 73 109
Pressed 135 273
Released 609 582