SubKorea > CYBER JAVA GAME > 벽돌깨기2 (Javanoid v1.45) > 소스 #7

// ## JAVANOID BUFFER CLASS ##################################
// this class implements a sort of triple buffer : 1 for the background
// image & the objects that you draw for a long time, 1 where the moving
// objects are drawn, and 1 for display (see update method).

abstract class jnbuffer extends Canvas {

 // Width & height of the game canvas
 protected int width;
 protected int height;
 
 Applet applet;
 
// On & off graphics for triple (!) buffering
 Graphics offGraphics, offBackGraphics;

 // Fontmetrics object
 FontMetrics fontMetrics;

 // Buffer & background images
 Image offImage, offBackImage, backImage;
 Dimension minSize;

 // Color for texts & background
 Color textColor = new Color (255, 223, 0);
 Color backColor = new Color (0, 0, 0);
  
 // Constructor
 public jnbuffer (Applet a, int w, int h) {
  applet = a;
  width = w; height = h;

  // Off images & graphics
  offImage     = applet.createImage(width, height);
  offBackImage = applet.createImage(width, height);
 
  offGraphics     = offImage.getGraphics();
  offBackGraphics = offBackImage.getGraphics();
 
  minSize = new Dimension(width, height);
  resize(width, height);

  fontMetrics = offGraphics.getFontMetrics();

  computeBackground(); clearBackground();
 
  }            // 위로

 // Compute background image
 void computeBackground() {
 
  int[] pix = new int[width * height];
  int index = 0;

  for (int j=0;j<height;j++) {

   int blue = 255 * j / (height - 1);

   for (int i=0;i<width;i++) {

      int red = 255 * i / (width - 1);
      pix[index++] = (255 << 24) | (red << 16) | blue;

    }
   }
  backImage = applet.createImage(new MemoryImageSource(width, height, pix, 0, width));
 
  }             // 위로

 public void drawImage(Image i, int x, int y) {
  offGraphics.drawImage(i, x, y, this);
  }

 public void drawString(String s, int x, int y) {
  offGraphics.setColor(textColor);
  offGraphics.drawString(s, x, y);
 
  }             // 위로

 public void drawPermanentString(String s, int x, int y) {
  offBackGraphics.setColor(textColor);
  offBackGraphics.drawString(s, x, y);
  }

 public void drawPermanentImage (Image i, int x, int y) {
  offBackGraphics.drawImage(i, x, y, this);
 
  }             // 위로

 public void clearPermanentImage (int x, int y, int w, int h) {
  // With JDK1.1, it should be
  // offBackGraphics.drawImage(backImage, x, y, x + w, y + h, x, y, x + w, y + h, this);
  Graphics tempGraphics = offBackImage.getGraphics();
  tempGraphics.clipRect(x, y, w, h);
  tempGraphics.drawImage(backImage, 0, 0, this);
  }

 public void clearBackground() {
  if (offBackGraphics==null) offBackGraphics = offBackImage.getGraphics();
  offBackGraphics.drawImage(backImage, 0, 0, this);
 
  }             // 위로

 // Update & paint methods
 public void paint(Graphics g) { update(g); }

 public void update(Graphics g) {

  if (g==null) g = this.getGraphics();
  g.drawImage(offImage, 0, 0, this);

  if (offGraphics==null) offGraphics = offImage.getGraphics();
  offGraphics.drawImage(offBackImage, 0, 0, this);
 
  }             // 위로

 // Dimension functions
 public int getStringWidth(String s) { return fontMetrics.stringWidth(s); }

 public int getStringHeight() { return fontMetrics.getHeight(); }

 public int getStringAscent() { return fontMetrics.getAscent(); }

 public int getWidth() { return width; }             // 위로

 public int getHeight() { return height; }

 // Canvas resizing methods
 public Dimension preferredSize() { return minimumSize(); }

 public synchronized Dimension minimumSize() { return minSize; }
 
 }             // 위로
 
  
// ## JAVANOID MOVING OBJECT #################################
// A javanoid moving object is an object that moves by itself. It has dX
// & dY values that give its movement in relative coordinates

abstract class jnmovingobject extends jnobject {

 // Initial & current movement of the object
 protected int dX0, dY0;
 protected int dX, dY;

 // Constructor
 public jnmovingobject(jnbuffer c, Image i, int w, int h, int x, int y, int dx, int dy) {
  super(c, i, w, h, x, y);
  dX0 = dx; dY0 = dy;
  dX = dx; dY = dy;
 
  }             // 위로

 public void die() { dX = 0; dY = 0; super.die(); }

 // Object movement settings
 public void setX(int x) {
  if (x > maxX)
    { X = maxX; invertDX(); }

  else if
    (x < minX) {X = minX; invertDX(); }

  else X = x;
 
  }              // 위로

 public void setY(int y) {
  if (y > maxY)
    die();
  else if (y < minY) { Y = minY; invertDY(); }
  else Y = y;
  }

 public void setDXDY(int dx, int dy) { dX = dx; dY = dy; }

 public void setDX(int dx) { dX = dx; }              // 위로

 public void setDY(int dy) { dY = dy; }

 public void invertDXDY() { dX = - dX; dY = - dY; }

 public void invertDX() { dX = - dX; }

 public void invertDY() { dY = - dY; }              // 위로

 public void reset() { dX = dX0; dY = dY0; super.reset(); }

 // Object life : move + drawing (dies when at the bottom of the screen)
 public void live() {

  if (alive) {
     setX(X + dX);
     setY(Y + dY);
     draw();
   }
  }              // 위로

 // Object requests
 public int getDX() { return dX; }

 public int getDY() { return dY; }
 
 }              // 위로