m3gcanvas.java

3D手机游戏开发实例源代码

import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;
import javax.microedition.m3g.*;
public class M3GCanvas extends GameCanvas implements Runnable {
    private Graphics3D g3d ;
    private World world;
    private Camera camera;
    private int iStartTime;
    private Graphics g;
    private int viewport_x;
    private int viewport_y;
    private int viewport_width;
    private int viewport_height;
    public M3GCanvas(){
        super(true);
         try {
                world = (World)Loader.load("/tunnel.m3g")[0];
                setupAspectRatio();
         } catch (Exception e) {
                e.printStackTrace();
         }
        iStartTime = (int)System.currentTimeMillis();
        Thread t = new Thread(this);
        t.start();
    }
    public void run() {
        Graphics g = getGraphics();
        while(true) {
        world.animate((int) System.currentTimeMillis() - iStartTime);   
        g.setColor( 255, 255, 255 );
        g.fillRect( 0, 0, getWidth(), getHeight() ); 
        g3d = Graphics3D.getInstance();
        g3d.bindTarget(g);
        try{
            g3d.render(world); 
        }catch(Exception e){
            System.err.println(e);
        }finally{
            g3d.releaseTarget();
        }
        flushGraphics();
            try {
                Thread.sleep(200); 
            }
            catch (InterruptedException e) {
                
            }
        }
    }
    void setupAspectRatio() {
        viewport_x = 0;
        viewport_y = 0;
        viewport_width = getWidth();
        viewport_height = getHeight();

        camera = world.getActiveCamera();

        float[] params = new float[4];
        int type = camera.getProjection(params);

        if (type != Camera.GENERIC) {
            //calculate window aspect ratio
            float waspect = viewport_width / viewport_height;

            if (waspect < params[1]) {
                float height = viewport_width / params[1];
                viewport_height = (int)height;
                viewport_y = (getHeight() - viewport_height) / 2;
            } else {
                float width = viewport_height * params[1];
                viewport_width = (int)width;
                viewport_x = (getWidth() - viewport_width) / 2;
            }
        }
    }
}