mybackground.java

Game_Anim_Java_MIDP_v1_0.zip详细的介绍了midp1.0中动画的制作

package example;

/**
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2003</p>
 * <p>Company: Sensible Development Ltd</p>
 * @author Alan Newman
 * @version 1.0
 */
import javax.microedition.lcdui.*;

public class MyBackground{

  private static int imageWidth, imageHeight;
  private static int tileWidth, tileHeight;
  private static int canvasWidth, canvasHeight;
  private Image[] images;
  private final String BACKGROUND_NAME="background";
  private final int BACKGROUND_FRAMES=6;
  private Image[] imgTile=new Image[BACKGROUND_FRAMES];
  private static Image imgBackground;
  private static int xBackground, yBackground;
  int xStart=0;
  int yStart=9;


  int iImageArray[][]={{0,1,0,0,0,0,3,0,0,5},
                         {1,0,4,0,0,0,0,4,4,0},
                         {0,0,3,0,3,4,4,2,0,0},
                         {0,2,4,3,4,2,4,2,0,0},
                         {0,4,0,0,3,3,4,0,0,0},
                         {0,0,0,0,3,1,0,0,1,1},
                         {0,0,0,3,3,1,0,2,1,1},
                         {0,0,2,3,4,0,0,0,0,0},
                         {0,0,0,0,0,0,0,5,0,0},
                         {0,0,0,0,0,0,0,0,0,0}};
  int arrayHeight=10;
  int arrayWidth=10;

  public MyBackground()
  {

    // load the images from the .jar
    imgTile=getImages(BACKGROUND_NAME,BACKGROUND_FRAMES);

    // set the canvas measurements to local class variables.
    canvasWidth=(MyCanvas.getCanvasWidth());
    canvasHeight=(MyCanvas.getCanvasHeight());

    // all character frame images are assumed
    // to be the same height and width
    tileWidth=imgTile[0].getWidth();
    tileHeight=imgTile[0].getHeight();

    // set the background image dimensions
    imageWidth=((canvasWidth/tileWidth)*tileWidth)+(tileWidth*2);
    imageHeight=((canvasWidth/tileHeight)*tileHeight)+tileHeight;
    createImage();

    xBackground=0;
    yBackground=-tileHeight;
    setImage();
  }
  public Image getImage(){return imgBackground;}


  public void draw(Graphics g)
  {
    g.drawImage(getImage(),xBackground,yBackground,g.LEFT|g.TOP);
  }

  public void setPosition()
  {
    //move the background to provide animation of moving landscape.
    boolean reset=false;

    // if the image exceeds the x-axis then reset it
    // and set the starting point for the next row in the image array
    // set the redraw flag for redrawing the image
    if(--xBackground==-tileWidth)
    {
      xBackground=0;
      if(++yStart>9)
      {
        yStart=0;
      }
      reset=true;
    }
    // if the images exceeds the y-axis then reset it
    // and set the stating point for the next column in the image array
    // set the redraw flag for redrawing the image
    if(++yBackground==0)
    {
      yBackground=-tileHeight;
      if(--xStart<0)
      {
        xStart=9;
      }
      reset=true;
    }

    // redraw the background image if reset=true
    if(reset)
    {
      setImage();
    }
  }

  private static void createImage()
  {
    // allocate memory to store the onscreen background image.
    // assuming all tiles are the same size, make the buffer
    // the screen size plus one row and column.
    imgBackground=Image.createImage(imageWidth, imageHeight);
  }

  public void setImage()
  {
    Graphics g = imgBackground.getGraphics();

    int currentWidth=0;
    int currentHeight=(imageHeight-tileHeight);
    int xOffset=xStart;
    int yOffset=yStart;

    // draw the tiles within the bounds of the allocated image buffer
    // draw from the starting from the current position within the image array.
    while (currentHeight>=0)
    {
      yOffset=yStart;
      while (currentWidth<imageWidth)
      {
        g.drawImage(imgTile[iImageArray[xOffset][yOffset]],currentWidth,currentHeight,g.LEFT | g.TOP);

        if(++yOffset>9)
        {
          yOffset=0;
        }
        currentWidth+=tileWidth;
      }

      if((--xOffset)<0)
      {
        xOffset=9;
      }

      currentWidth=0;
      currentHeight-=tileHeight;
    }

  }

  private Image[] getImages(String imgName, int frames)
  {
    return ExampleMidlet.getImages(imgName, frames);
  }
}