canvas.java

java编的一个火焰程序

package skyrocket;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.Random;
import java.util.TreeSet;

import javax.swing.Timer;

class Canvas extends java.awt.Canvas {




double gravity = 1.0;
double damp = 0.75;
double skyrocketVelocity = -82;
int skyrocketWidth = 4;
int skyrocketHeight = 8;
int pieceNumber = 200;
double pieceInitialVelocity = 72;
double pieceDarkerFactor = 0.90;
int pieceWidth = 1;
int pieceHeight = 2;
double traceDarkerFactor = 0.70;
int frameDelay = 40;
int border = 10;

Random random = new Random( System.currentTimeMillis() );
int currentTime;
TreeSet things = new TreeSet();
Skyrocket currentSkyrocket;
Image offscreenImage;
Graphics offscreenGraphics;

void init() {
	setBackground( Color.BLACK );
	offscreenImage = createImage( getWidth(), getHeight() );
	offscreenGraphics = offscreenImage.getGraphics();
	addMouseListener( new MouseAdapter() {
		public void mousePressed( MouseEvent e ) {
			onMousePress( e );
		}
		public void mouseReleased( MouseEvent e ) {
			onMouseRelease( e );
		}
	} );
	addKeyListener( new KeyAdapter() {
		public void keyPressed( KeyEvent e ) {
			onKeyPress( e );
		}
	} );
	new Timer( frameDelay, new ActionListener() {
		public void actionPerformed( ActionEvent e ) {
			repaint();
		}
	} ).start();
	requestFocus();
}

void onMousePress( MouseEvent e ) {

	if( currentSkyrocket != null )
		currentSkyrocket.explode();

	int r = random.nextInt( 256 );
	int g = random.nextInt( 256 );
	int b = random.nextInt( 256 );
	int max = r > g ? r : g;
	max = max > b ? max : b;
	double brighter = 255.0 / max;
	r = (int) ( r * brighter );
	g = (int) ( g * brighter );
	b = (int) ( b * brighter );
	Color color = new Color( r, g, b );

	currentSkyrocket = new Skyrocket( this, color, e.getX() );
	things.add( currentSkyrocket );

}

void onMouseRelease( MouseEvent e ) {
	if( currentSkyrocket != null ) {
		currentSkyrocket.explode();
		currentSkyrocket = null;
	}
}

void onKeyPress( KeyEvent e ) {
	if( e.getKeyCode() == KeyEvent.VK_Q ) { gravity += 0.01; }
	if( e.getKeyCode() == KeyEvent.VK_A ) { gravity -= 0.01; if(gravity<0) gravity=0; }
	if( e.getKeyCode() == KeyEvent.VK_W ) { damp += 0.01; if(damp>1) damp=1; }
	if( e.getKeyCode() == KeyEvent.VK_S ) { damp -= 0.01; if(damp<0) damp=0; }
	if( e.getKeyCode() == KeyEvent.VK_E ) { skyrocketVelocity -= 1; }
	if( e.getKeyCode() == KeyEvent.VK_D ) { skyrocketVelocity += 1; if(skyrocketVelocity>0) skyrocketVelocity=0; }
	if( e.getKeyCode() == KeyEvent.VK_R ) { skyrocketWidth += 1; }
	if( e.getKeyCode() == KeyEvent.VK_F ) { skyrocketWidth -= 1; if(skyrocketWidth<1) skyrocketWidth=1; }
	if( e.getKeyCode() == KeyEvent.VK_T ) { skyrocketHeight += 1; }
	if( e.getKeyCode() == KeyEvent.VK_G ) { skyrocketHeight -= 1; if(skyrocketHeight<1) skyrocketHeight=1; }
	if( e.getKeyCode() == KeyEvent.VK_Y ) { pieceNumber += 10; }
	if( e.getKeyCode() == KeyEvent.VK_H ) { pieceNumber -= 10; if(pieceNumber<0) pieceNumber=0; }
	if( e.getKeyCode() == KeyEvent.VK_U ) { pieceInitialVelocity += 1; }
	if( e.getKeyCode() == KeyEvent.VK_J ) { pieceInitialVelocity -= 1; if(pieceInitialVelocity<0) pieceInitialVelocity=0; }
	if( e.getKeyCode() == KeyEvent.VK_I ) { pieceDarkerFactor += 0.01; if(pieceDarkerFactor>1) pieceDarkerFactor=1; }
	if( e.getKeyCode() == KeyEvent.VK_K ) { pieceDarkerFactor -= 0.01; if(pieceDarkerFactor<0) pieceDarkerFactor=0; }
	if( e.getKeyCode() == KeyEvent.VK_O ) { pieceWidth += 1; }
	if( e.getKeyCode() == KeyEvent.VK_L ) { pieceWidth -= 1; if(pieceWidth<1) pieceWidth=1; }
	if( e.getKeyCode() == KeyEvent.VK_P ) { pieceHeight += 1; }
	if( e.getKeyCode() == KeyEvent.VK_SEMICOLON ) { pieceHeight -= 1; if(pieceHeight<1) pieceHeight=1; }
	if( e.getKeyCode() == KeyEvent.VK_OPEN_BRACKET ) { traceDarkerFactor += 0.01; if(traceDarkerFactor>1) traceDarkerFactor=1; }
	if( e.getKeyCode() == KeyEvent.VK_QUOTE ) { traceDarkerFactor -= 0.01; if(traceDarkerFactor<0) traceDarkerFactor=0; }
System.out.println(
"g"+(int)(gravity*100)+" "+
"d"+(int)(damp*100)+" "+
"sv"+(int)(-skyrocketVelocity*1)+" "+
"sw"+(int)(skyrocketWidth*1)+" "+
"sh"+(int)(skyrocketHeight*1)+" "+
"pn"+(int)(pieceNumber*1)+" "+
"pv"+(int)(pieceInitialVelocity*1)+" "+
"pf"+(int)(pieceDarkerFactor*100)+" "+
"pw"+(int)(pieceWidth*1)+" "+
"ph"+(int)(pieceHeight*1)+" "+
"tf"+(int)(traceDarkerFactor*100)
);
}

public void update( Graphics g ) {
	paint( g );
}

long totalPaintTime;
public void paint( Graphics g ) {
	if( offscreenImage == null )
		return;
long time1 = System.currentTimeMillis();
	System.gc();
long time2 = System.currentTimeMillis();
	offscreenGraphics.clearRect( 0, 0, getWidth(), getHeight() );
	TreeSet things2 = new TreeSet();
	while( ! things.isEmpty() ) {
		Thing thing = (Thing) things.first();
		things.remove( thing );
		thing.paint();
		if( thing.stateDead || thing.stateX<-border || thing.stateY>getWidth()+border || thing.stateY<-border || thing.stateY>getHeight()+border ) {
		} else {
			things2.add( thing );
		}
	}
	things = things2;
	g.drawImage( offscreenImage, 0, 0, this );
long time3 = System.currentTimeMillis();
totalPaintTime += time3 - time1;
	currentTime++;
//System.out.println( "("+(time2-time1)+") "+totalPaintTime+" / "+currentTime+" = "+totalPaintTime/currentTime );
}




}