import java.awt.*;
import java.awt.image.*;

public class Draw3x
{

   public static void pause(int n) throws Exception
   {
      Thread.sleep( 100 * n );   // pause for 100*n msec
   }

    /* ===========================================================
       The "move_left" method copies the "image" stored in
       the variable "pixel" one column to the left

             col  col+1
              . <-- .
              . <-- .
              . <-- .
       =========================================================== */
    public static void move_left(int[][] pixel)
    {
       int ncols, nrows;

       for ( int col = 0; col < 399; col++ )
          for ( int row = 0; row < 300; row++ )
              pixel[col][row] = pixel[col+1][row];

       /* ---------------------------------------------
          Fill the right most column with BLACK pixels
          --------------------------------------------- */
       for ( int row = 0; row < 300; row++ )
          pixel[399][row] = 0;  // 0 = BLACK
    }



   static public void main(String[] args) throws Exception
   {
      final int YELLOW = 0xFFFF00;
      final int BLACK  = 0x000000;

      /* ------------------------------------------------
         Preparing to draw picture...
         ------------------------------------------------ */
      MyCanvas pic = new MyCanvas();        // Make a canvas (2 dim array)
      Frame f = new Frame( "My image" );    // Create a window

      f.add("Center", pic);                 // Put the canvas in the window
      f.setSize(400,300);                   // Set size of the window
      f.setVisible(true);                   // Make window visible 

      int[][] a = new int[400][300];        // This array hold the picture
      int row, col;

      for (col = 0; col < 400; col++ ) 
         for (row = 0; row < 300; row++ ) 
             a[col][row] = BLACK;

      /* --------------------------------------------------
         Make a vertical yellow line (col coord unchanged)
         -------------------------------------------------- */
      a[100][191] = YELLOW; a[100][192] = YELLOW; a[100][193] = YELLOW;
      a[100][194] = YELLOW; a[100][195] = YELLOW; a[100][196] = YELLOW;
      a[100][197] = YELLOW; a[100][198] = YELLOW; a[100][199] = YELLOW;
      a[100][200] = YELLOW; a[100][201] = YELLOW; a[100][202] = YELLOW;
      a[100][203] = YELLOW; a[100][204] = YELLOW; a[100][205] = YELLOW;
      a[100][206] = YELLOW; a[100][207] = YELLOW; a[100][208] = YELLOW;
      a[100][209] = YELLOW; a[100][210] = YELLOW; a[100][211] = YELLOW;

      /* -----------------------------------------------------
         Make a horizontal yellow line (row coord unchanged)
         ----------------------------------------------------- */
      a[96][201] = YELLOW; a[95][201] = YELLOW; a[94][201] = YELLOW;
      a[99][201] = YELLOW; a[98][201] = YELLOW; a[97][201] = YELLOW;
      a[101][201] = YELLOW; a[102][201] = YELLOW; a[103][201] = YELLOW;
      a[104][201] = YELLOW; a[105][201] = YELLOW; a[106][201] = YELLOW;


      for ( int k = 0; k < 120; k++ )
      {
         pic.draw(a);       // Draw the picture in a[][]
         pause(1);
         move_left(a);
      }

      System.exit(0);
   }
}