Javaでお絵書きしてみる (3)

import java.util.*;
import java.awt.*;
import java.awt.geom.*;
public class Sample07 {
    public static void tree(ToyGraphics tg, int x, int y, int w, int h) {
	int[] xp = { x+w/2, x+w/4, x+w/3, x,       x+w,      x+w*2/3, x+w*3/4 };
	int[] yp = { y,     y+h/3, y+h/3, y+h*2/3, y+h*2/3, y+h/3, y+h/3  };
	tg.g2d.setColor(new Color(50,255,50));
	tg.g2d.fill(new Polygon(xp,yp,xp.length));

	int[] xp2 = { x+w/3,   x+w/3, x+w*2/3, x+w*2/3 };
	int[] yp2 = { y+h*2/3, y+h,   y+h,     y+h*2/3 };
	tg.g2d.setColor(new Color(200,128,50));
	tg.g2d.fill(new Polygon(xp2,yp2,xp2.length));
    }
    public static void snowman(ToyGraphics tg, int x, int y, int w, int h) {
	tg.g2d.setColor(new Color(232,232,232));
	tg.g2d.fill(new Arc2D.Double(x+w/4, y, w/2, h/2, 0, 360, Arc2D.CHORD));
	tg.g2d.fill(new Arc2D.Double(x, y+h*2/5, w, h*3/5, 0, 360, Arc2D.CHORD));

	tg.g2d.setColor(new Color(128,128,128));
	tg.g2d.fill(new Arc2D.Double(x+w*(1.0/2 - 2.0/10), y+h/8, w/10, h/8, 0, 360, Arc2D.CHORD));
	tg.g2d.fill(new Arc2D.Double(x+w*(1.0/2 + 1.0/10), y+h/8, w/10, h/8, 0, 360, Arc2D.CHORD));
    }

    static int W=1280;
    static int H=720;
    static int N=20;
    public static void main(String[] args) {
	ToyGraphics tg = new ToyGraphics();

	int[][] trees = new int[500][2];
	Random rand = new Random(123);
	for (int i=0; i<trees.length; i++) {
	    trees[i][0] = rand.nextInt(W * N);
	    trees[i][1] = rand.nextInt(2*H) - H;
	}
	
	int x = 0;
	int y = 0;
	int sx = W/8;
	int sy = H/2;

	while (x < W) {
	    tg.g2d.setColor(new Color(0,0,0));
	    tg.g2d.fill(new Rectangle(0,0,W,H));

	    x += 10;

	    for (int i=0; i<trees.length; i++) {
		tree(tg, trees[i][0]-x+sx, trees[i][1]-y+sy, 100, 100);
	    }

	    snowman(tg,sx,sy,100,100);
	    
	    tg.repaint();

	    try {
		Thread.sleep(50);   // 50 msec
	    } catch (Exception e) {}
	}

	tg.repaint();
    }
}

% javac Sample07.java    ← 青文字の部分をタイプします。%はシェルのプロンプトのつもりです。
% java Sample07  

public class GReport03 {
    ....(略)...

    public static void main(Strings[] args) {
	ToyGraphics tg = new ToyGraphics();
        ....(略)...

	for (double clock=0.0; clock < 1.0; clock += 0.001) {
            tg.g2d.setColor(new Color(0,0,0));
	    tg.g2d.fill(new Rectangle(0,0,1280,720));  // 画面全体を黒く塗り潰して

           ....(略)...

            // clock の値によって位置、方向、大きさなどを変更して画像を描く
 
           ....(略)...

	    tg.repaint();    // clock時点での画像を表示する

	    try {
		Thread.sleep(50);   // 50 msec だけプログラムの実行を停止する
	    } catch (Exception e) {}

        }
    }
}