android:surfaceview小实例

package com.chnfuture.viewporttest;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;

import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;

import android.app.Activity;
import android.opengl.GLSurfaceView;
import android.opengl.GLSurfaceView.Renderer;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;

public class MainActivity extends Activity {

	GLSurfaceView glView;
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        
        glView = new GLSurfaceView(this);
        glView.setRenderer(new SimpleRenderer());
        setContentView(glView);
    }
    
    class SimpleRenderer implements Renderer
    {

        @Override
        public void onDrawFrame(GL10 gl)
        {
            ByteBuffer byteBuffer = ByteBuffer.allocateDirect(6 * 2 * 4);
            byteBuffer.order(ByteOrder.nativeOrder());
            FloatBuffer vertices = byteBuffer.asFloatBuffer();
            // 定义两个三角形的六个顶点
            vertices.put(new float[] {
            120.0f, 200.0f,
            360.0f, 200.0f,
            360.0f, 600.0f,
            120.0f, 200.0f,
            360.0f, 600.0f,
            120.0f, 600.0f
            });
            vertices.flip();
            
            gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
            gl.glVertexPointer(2, GL10.GL_FLOAT, 0, vertices);
            gl.glDrawArrays(GL10.GL_TRIANGLES, 0, 3);
            gl.glDrawArrays(GL10.GL_TRIANGLES, 3, 3);

        }

        @Override
        public void onSurfaceChanged(GL10 arg0, int arg1, int arg2) 
        {
            
        }

        @Override
        public void onSurfaceCreated(GL10 gl, EGLConfig arg1) 
        {
            gl.glClearColor(0,0,1,1);
            gl.glColor4f(1.0f, 0.0f, 0.0f, 0.0f);
            gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
            // 整个屏幕作为视口
            gl.glViewport(0, 0, 480, 800);
            //gl.glViewport(0, 0, 240, 400);
            gl.glMatrixMode(GL10.GL_PROJECTION);
            gl.glLoadIdentity();
            gl.glOrthof(0, 240, 0, 400, 1, -1);
        }
    }
    
}