mysprite.java

J2ME编程的50个例子,适合掌上系统的编程

package demo;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;


public class MySprite extends MyLayer{
	public static final int TRANS_NONE 		= 0;	//不转换
	public static final int TRANS_MIRROR 		= 1;	//镜像翻转
	public static final int TRANS_TYPE_NUM	= 2;	//转换类型总数
	protected int		m_nTransform = TRANS_NONE;		//转换类型
	
	protected int 		m_nFrame;						//当前的帧编号
	protected int		m_nFrameCols;					//每行的帧数
	protected int		m_nFrameRows;					//每列的帧数
	protected int		m_nRefX;						//参考点的X坐标
	protected int		m_nRefY;						//参考点的Y坐标
	
	
	public MySprite(Image image, int frameWidth, int frameHeight){
		super();
		if( image == null ){
			System.out.print("(MySprite)image is null!");
			return;
		}
		if( image.getWidth() % frameWidth != 0 ){
			System.out.print("(MySprite)frameWidth is wrong!");
			return;
		}
		if( image.getHeight() % frameHeight != 0 ){
			System.out.print("(MySprite)frameHeight is wrong!");
			return;
		}
		m_Image 		= image;
		m_nWidth 		= frameWidth;
		m_nHeight		= frameHeight;
		m_bVisible		= true;
		m_nFrame		= 0;
		m_nFrameCols	= image.getWidth()/m_nWidth;
		m_nFrameRows	= image.getHeight()/m_nHeight;
		m_nRefX			= frameWidth / 2;
		m_nRefY			= frameHeight / 2;
		m_nTransform	= TRANS_NONE;
	}
	//设置当前的帧编号
	public void setFrame(int sequenceIndex){
		if( sequenceIndex < 0 || sequenceIndex >= m_nFrameCols * m_nFrameRows ){
			System.out.print("(setFrame)sequenceIndex is wrong!");
			return;
		}
		m_nFrame = sequenceIndex;
	}
	//获取当前的帧编号
	public int getFrame(){
		return m_nFrame;
	}
	//获取帧的总数
	public int getFrameSequenceLength(){
		return m_nFrameCols * m_nFrameRows;
	}
	//获取参考点的X坐标
	public int getRefPixelX(){
		return m_nRefX;
	}
	//获取参考点的Y坐标
	public int getRefPixelY(){
		return m_nRefY;
	}
	//设置参考点
	public void defineReferencePixel(int x, int y) {
		m_nRefX = x;
		m_nRefY = y;
	}
	//通过参考点，设置精灵位置
	public void setRefPixelPosition(int x, int y) {
		setPosition(x - m_nRefX, y - m_nRefY);
	}
	//设置精灵图像的转换
	public void setTansform(int transform){
		if( transform < 0 || transform >= TRANS_TYPE_NUM ){
			System.out.print("(setTansform)transform is wrong!");
			return;
		}
		m_nTransform = transform;
	}
	//显示精灵图像
    public void paint(Graphics g){ 
    	if( !m_bVisible )
    		return;
    	//保存原有的切割区域
    	int clipx = g.getClipX();
    	int clipy = g.getClipY();
    	int clipw = g.getClipWidth();
    	int cliph = g.getClipHeight();
    	//设置图片的绘制位置
    	int x = m_nX - (m_nFrame % m_nFrameCols) * m_nWidth;
    	int y = m_nY - (m_nFrame / m_nFrameCols) * m_nHeight;
    	//根据转换类型，显示图像
    	switch( m_nTransform ){
    	case TRANS_NONE:
    		g.setClip(m_nX, m_nY, m_nWidth, m_nHeight);   
	    	g.drawImage(m_Image, x, y, 0);
	    	break;
    	case TRANS_MIRROR:
    		for( int i = 0; i < m_nWidth; i ++  ){
				//设置切割区域是1列            
				g.setClip(m_nX + i, m_nY, 1, m_nHeight);
				//绘制图片            
				g.drawImage(m_Image, x - ( 2 * (m_nRefX-i) ), y, 0);
    		}
	    	break;
    	}
    	//恢复切割区域
    	g.setClip(clipx, clipy, clipw, cliph);
	}
}