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);
}
}

}