Android openGL(2) 实现一个旋转的有纹理的正方体

package com.MyOpengl;

import android.app.Activity;

import android.opengl.GLSurfaceView;

import android.os.Bundle;

import android.view.WindowManager;

public class MyOpengl extends Activity {

GLSurfaceView mySurfaceView ;

    /** Called when the activity is first created. */

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        

        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, 

        WindowManager.LayoutParams.FLAG_FULLSCREEN) ;

        

        mySurfaceView = new GLSurfaceView(this) ;

        mySurfaceView.setRenderer(new MyRender(this)) ;

        setContentView(mySurfaceView) ;

        

    }

}    

package com.MyOpengl;

import javax.microedition.khronos.egl.EGLConfig;

import javax.microedition.khronos.opengles.GL10;

import android.content.Context;

import android.opengl.GLSurfaceView.Renderer;

public class MyRender implements Renderer{

Cube mCube ;

Context mContext ;

public MyRender(Context mContext)

{

this.mContext=mContext ;

mCube = new Cube(mContext) ;

}

@Override

public void onDrawFrame(GL10 gl) {

// 清除屏幕和深度缓存

gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT) ;

  mCube.OnDraw(gl);

}

@Override

public void onSurfaceChanged(GL10 gl, int width, int height) {

float ratio = (float) width/height ;

//设置Opengl场景的大小

gl.glViewport(0, 0, width, height) ;

//设置投影矩阵

gl.glMatrixMode(GL10.GL_PROJECTION) ;

//重置投影矩阵

gl.glLoadIdentity() ;

//设置视口的大小

gl.glFrustumf(-ratio, ratio, -1, 1,1, 10) ;

//选择模型观察矩阵

gl.glMatrixMode(GL10.GL_MODELVIEW) ;

//重置模型观察矩阵

gl.glLoadIdentity() ;

}

@Override

public void onSurfaceCreated(GL10 gl, EGLConfig config) {

//启用阴影平滑

gl.glShadeModel(GL10.GL_SMOOTH) ;

//黑色背景

gl.glClearColor(0, 0, 0, 0) ;

//设置深度缓存

gl.glClearDepthf(1.0f) ;

//启用深度测试

gl.glEnable(GL10.GL_DEPTH_TEST) ;

//所作深度测试类型

gl.glDepthFunc(GL10.GL_LEQUAL) ;

//告诉系统对透视进行修正

gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST) ;

//初始化 纹理

mCube.initTexture2D(gl);

}

}

package com.MyOpengl;

import java.io.InputStream;

import java.nio.ByteBuffer;

import java.nio.ByteOrder;

import java.nio.FloatBuffer;

import javax.microedition.khronos.opengles.GL10;

import android.content.Context;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.opengl.GLUtils;

public class Cube {

Context mContext;

float roteangle;

FloatBuffer CubeVetBuffer;

FloatBuffer TextureVetBuffer;

int mTextureID;

float[] TextureVerex = new float[] {

// front

1f, 0, 0, 0, 0, 1f, 1f, 1f,

// right

0, 0, 0, 1f, 1f, 1f, 1f, 0,

// left

1f, 0, 0, 0, 0, 1f, 1f, 1f,

// back

0, 0, 0, 1f, 1f, 1f, 1f, 0,

// bottom

0, 1f, 1f, 1f, 1f, 0, 0, 0,

// top

1f, 1f, 1f, 0, 0, 0, 0, 1f };

float[] CubeVertex = new float[] {

// front

0.0f, 1.0f, 1.0f,//

1.0f, 1.0f, 1.0f,//

1.0f, 0.0f, 1.0f,//

0.0f, 0.0f, 1.0f,//

// right

1.0f, 1.0f, 1.0f, //

1.0f, 1.0f, 0.0f, //

1.0f, 0.0f, 0.0f,//

1.0f, 0.0f, 1.0f,//

// left

0.0f, 1.0f, 1.0f, //

0.0f, 0.0f, 1.0f, //

0.0f, 0.0f, 0.0f,//

0.0f, 1.0f, 0.0f,//

// back

0.0f, 0.0f, 0.0f,//

1.0f, 0.0f, 0.0f,//

1.0f, 1.0f, 0.0f,//

0.0f, 1.0f, 0.0f,//

// bottom

0.0f, 0.0f, 0.0f,//

1.0f, 0.0f, 0.0f,//

1.0f, 0.0f, 1.0f,//

0.0f, 0.0f, 1.0f,//

// top

0.0f, 1.0f, 1.0f,//

0.0f, 1.0f, 0.0f,//

1.0f, 1.0f, 0.0f,//

1.0f, 1.0f, 1.0f //

};

public Cube(Context mContext) {

this.mContext = mContext;

// 分配Buffer给声明的FloatBuffer

ByteBuffer vbb = ByteBuffer.allocateDirect(CubeVertex.length * 4);

vbb.order(ByteOrder.nativeOrder());

CubeVetBuffer = vbb.asFloatBuffer();

ByteBuffer tbb = ByteBuffer.allocateDirect(TextureVerex.length * 4);

tbb.order(ByteOrder.nativeOrder());

TextureVetBuffer = tbb.asFloatBuffer();

// FloatBuffer赋值

CubeVetBuffer.put(CubeVertex);

TextureVetBuffer.put(TextureVerex);

CubeVetBuffer.position(0);

TextureVetBuffer.position(0);

}

public void OnDraw(GL10 gl) {

gl.glLoadIdentity();

// 一般在绘制开始时，使用glLoadIdentity()函数，在绘制中一般使用glPushMatrix()和glPopMatrix()控制一个图元

gl.glPushMatrix();

gl.glTranslatef(0f, 0f, -2.5f);

gl.glRotatef(roteangle, 0, 1, 0);

gl.glRotatef(10, 1, 0, 0);

// 绑定纹理

gl.glBindTexture(GL10.GL_TEXTURE_2D, mTextureID);

gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);

gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);

gl.glVertexPointer(3, GL10.GL_FLOAT, 0, CubeVetBuffer);

// 指定纹理映射，由于是2D纹理所以第一个参数为2

gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, TextureVetBuffer);

// 绘制Cube

for (int i = 0; i < 6; i++)

gl.glDrawArrays(GL10.GL_TRIANGLE_FAN, i * 4, 4);

gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);

gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);

gl.glPopMatrix();

roteangle += 0.5;

}

public void initTexture2D(GL10 gl) {

// 允许2D贴图,纹理

gl.glEnable(GL10.GL_TEXTURE_2D);

// 创建纹理

int textures[] = new int[1];

gl.glGenTextures(1, textures, 0);

mTextureID = textures[0];

// 设置要使用的纹理

gl.glBindTexture(GL10.GL_TEXTURE_2D, mTextureID);

Bitmap bitmap;

// 获取图片

InputStream is = mContext.getResources().openRawResource(

R.drawable.texture);

try {

bitmap = BitmapFactory.decodeStream(is);

} finally {

try {

is.close();

} catch (Exception e) {

}

}

// 生成纹理

GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);

// 线性滤波，使得纹理从很远和很近时，显示都很平滑

gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER,

GL10.GL_LINEAR);

gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER,

GL10.GL_LINEAR);

// bitmap回收

bitmap.recycle();

}

}