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第14章 片元着色器的妙用/Sample14_1/.classpath

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+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="src" path="gen"/>
+	<classpathentry kind="con" path="com.android.ide.eclipse.adt.ANDROID_FRAMEWORK"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

第14章 片元着色器的妙用/Sample14_1/.project

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+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Sample14_1</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>com.android.ide.eclipse.adt.ResourceManagerBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>com.android.ide.eclipse.adt.PreCompilerBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>com.android.ide.eclipse.adt.ApkBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>com.android.ide.eclipse.adt.AndroidNature</nature>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>

第14章 片元着色器的妙用/Sample14_1/.settings/org.eclipse.jdt.core.prefs

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+#Wed Jan 05 21:56:15 CST 2011
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
+org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
+org.eclipse.jdt.core.compiler.compliance=1.6
+org.eclipse.jdt.core.compiler.debug.lineNumber=generate
+org.eclipse.jdt.core.compiler.debug.localVariable=generate
+org.eclipse.jdt.core.compiler.debug.sourceFile=generate
+org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
+org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
+org.eclipse.jdt.core.compiler.source=1.6

第14章 片元着色器的妙用/Sample14_1/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+      android:versionCode="1"
+      android:versionName="1.0" package="com.bn.Sample14_1">
+    <application android:icon="@drawable/icon" android:label="@string/app_name">
+        <activity android:label="@string/app_name" android:name=".Sample14_1_Activity">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+    <uses-sdk android:targetSdkVersion="8"></uses-sdk>
+</manifest> 

第14章 片元着色器的妙用/Sample14_1/assets/frag.sh

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+precision mediump float;
+varying vec2 mcLongLat;//接收从顶点着色器过来的参数
+void main()                         
+{                       
+   vec3 bColor=vec3(0.678,0.231,0.129);//砖块的颜色
+   vec3 mColor=vec3(0.763,0.657,0.614);//间隔的颜色
+   vec3 color;
+   
+   //计算当前位于奇数还是偶数行
+   int row=int(mod((mcLongLat.y+90.0)/12.0,2.0));
+   //计算当前是否在此行的砖块垂直区间中的辅助变量
+   float ny=mod(mcLongLat.y+90.0,12.0);
+   //奇偶数行x偏移
+   float oeoffset=0.0;
+   //计算当前是否在此列的砖块水平区间中的辅助变量
+   float nx;
+   
+   if(ny>10.0)
+   {//不在此行的砖块垂直区间中
+     color=mColor;
+   }
+   else
+   {//在此行的砖块垂直区间中
+     if(row==1)
+     {//若为奇数行则加上列偏移
+        oeoffset=11.0;
+     }
+     //计算当前是否在此列的砖块水平区间中的辅助变量
+     nx=mod(mcLongLat.x+oeoffset,22.0);
+     if(nx>20.0)
+     {//不在此列的砖块水平区间中
+        color=mColor;
+     }
+     else
+     {//在此列的砖块水平区间中
+        color=bColor;
+     }
+   } 
+   //将计算出的颜色给此片元
+   gl_FragColor=vec4(color,0);
+}     

第14章 片元着色器的妙用/Sample14_1/assets/vertex.sh

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+uniform mat4 uMVPMatrix; //总变换矩阵
+attribute vec3 aPosition;  //顶点位置
+attribute vec2 aLongLat;   //顶点经纬度
+varying vec2 mcLongLat;
+void main()     
+{                   
+   //根据总变换矩阵计算此次绘制此顶点位置         		
+   gl_Position = uMVPMatrix * vec4(aPosition,1); 
+   //将顶点的经纬度传给片元着色器
+   mcLongLat=aLongLat;
+}                      

第14章 片元着色器的妙用/Sample14_1/default.properties

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+# This file is automatically generated by Android Tools.
+# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
+# 
+# This file must be checked in Version Control Systems.
+# 
+# To customize properties used by the Ant build system use,
+# "build.properties", and override values to adapt the script to your
+# project structure.
+
+# Indicates whether an apk should be generated for each density.
+split.density=false
+# Project target.
+target=android-8

第14章 片元着色器的妙用/Sample14_1/gen/com/bn/Sample14_1/R.java

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+/* AUTO-GENERATED FILE.  DO NOT MODIFY.
+ *
+ * This class was automatically generated by the
+ * aapt tool from the resource data it found.  It
+ * should not be modified by hand.
+ */
+
+package com.bn.Sample14_1;
+
+public final class R {
+    public static final class attr {
+    }
+    public static final class drawable {
+        public static final int icon=0x7f020000;
+    }
+    public static final class id {
+        public static final int main_liner=0x7f050000;
+    }
+    public static final class layout {
+        public static final int main=0x7f030000;
+    }
+    public static final class string {
+        public static final int app_name=0x7f040000;
+    }
+}

第14章 片元着色器的妙用/Sample14_1/res/layout/main.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:orientation="vertical"
+    android:layout_width="fill_parent"
+    android:layout_height="fill_parent"
+    android:id="@+id/main_liner"
+    >
+</LinearLayout>

第14章 片元着色器的妙用/Sample14_1/res/values/strings.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">Sample14_1</string>
+</resources>

第14章 片元着色器的妙用/Sample14_1/src/com/bn/Sample14_1/Ball.java

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+package com.bn.Sample14_1;
+
+import java.nio.ByteBuffer;
+
+import static com.bn.Sample14_1.Constant.*;
+
+import java.nio.ByteOrder;
+import java.nio.FloatBuffer;
+import java.util.ArrayList;
+import android.opengl.GLES20;
+
+//球
+public class Ball {
+	int mProgram;//自定义渲染管线着色器程序id
+	int muMVPMatrixHandle;//总变换矩阵引用
+	int maPositionHandle; //顶点位置属性引用
+	int maLongLatHandle; //顶点经纬度属性引用
+	String mVertexShader;//顶点着色器代码脚本
+	String mFragmentShader;//片元着色器代码脚本
+
+	FloatBuffer mVertexBuffer;//顶点坐标数据缓冲
+	FloatBuffer   mLongLatBuffer;//顶点经纬度数据缓冲
+	int vCount = 0;
+	float yAngle = 0;//绕y轴旋转的角度
+	float xAngle = 0;//绕x轴旋转的角度
+	float zAngle = 0;//绕z轴旋转的角度
+	float r = 0.8f;
+	public Ball(MySurfaceView mv) {
+		//初始化顶点坐标与着色数据
+		initVertexData();
+		//初始化shader
+		initShader(mv);
+	}
+
+	//初始化顶点坐标数据的方法
+	public void initVertexData() {
+		//顶点坐标数据的初始化================begin============================
+		ArrayList<Float> alVertix = new ArrayList<Float>();//存放顶点坐标的ArrayList
+    	ArrayList<Float> alLongLat=new ArrayList<Float>();//存放顶点经纬度的ArrayList
+		final int angleSpan = 10;//将球进行单位切分的角度
+		for (int vAngle = -90; vAngle < 90; vAngle = vAngle + angleSpan)//垂直方向angleSpan度一份
+		{
+			for (int hAngle = 0; hAngle <= 360; hAngle = hAngle + angleSpan)//水平方向angleSpan度一份
+			{//纵向横向各到一个角度后计算对应的此点在球面上的坐标    	
+        		float x0=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle))*Math.cos(Math.toRadians(hAngle)));
+        		float y0=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle))*Math.sin(Math.toRadians(hAngle)));
+        		float z0=(float)(r*UNIT_SIZE*Math.sin(Math.toRadians(vAngle)));        		
+        		float long0=hAngle; float lat0=vAngle;
+        		
+        		float x1=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle))*Math.cos(Math.toRadians(hAngle+angleSpan)));
+        		float y1=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle))*Math.sin(Math.toRadians(hAngle+angleSpan)));
+        		float z1=(float)(r*UNIT_SIZE*Math.sin(Math.toRadians(vAngle)));
+        		float long1=hAngle+angleSpan; float lat1=vAngle;
+        		
+        		float x2=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle+angleSpan))*Math.cos(Math.toRadians(hAngle+angleSpan)));
+        		float y2=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle+angleSpan))*Math.sin(Math.toRadians(hAngle+angleSpan)));
+        		float z2=(float)(r*UNIT_SIZE*Math.sin(Math.toRadians(vAngle+angleSpan)));
+        		float long2=hAngle+angleSpan; float lat2=vAngle+angleSpan;
+        		
+        		float x3=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle+angleSpan))*Math.cos(Math.toRadians(hAngle)));
+        		float y3=(float)(r*UNIT_SIZE*Math.cos(Math.toRadians(vAngle+angleSpan))*Math.sin(Math.toRadians(hAngle)));
+        		float z3=(float)(r*UNIT_SIZE*Math.sin(Math.toRadians(vAngle+angleSpan)));
+        		float long3=hAngle; float lat3=vAngle+angleSpan;
+        		
+        		//将计算出来的XYZ坐标加入存放顶点坐标的ArrayList        		
+        		alVertix.add(x1);alVertix.add(y1);alVertix.add(z1);  
+        		alVertix.add(x3);alVertix.add(y3);alVertix.add(z3);
+        		alVertix.add(x0);alVertix.add(y0);alVertix.add(z0);
+        		      		
+        		alVertix.add(x1);alVertix.add(y1);alVertix.add(z1);
+        		alVertix.add(x2);alVertix.add(y2);alVertix.add(z2);
+        		alVertix.add(x3);alVertix.add(y3);alVertix.add(z3);
+        		
+        		//将计算出来的顶点经纬度加入存放顶点经纬度的ArrayList        		
+        		alLongLat.add(long1);alLongLat.add(lat1);
+        		alLongLat.add(long3);alLongLat.add(lat3);
+        		alLongLat.add(long0);alLongLat.add(lat0);
+        		
+        		alLongLat.add(long1);alLongLat.add(lat1);
+        		alLongLat.add(long2);alLongLat.add(lat2);
+        		alLongLat.add(long3);alLongLat.add(lat3);
+        	}
+		}
+		vCount = alVertix.size() / 3;//顶点的数量为坐标值数量的1/3，因为一个顶点有3个坐标
+
+		//将alVertix中的坐标值转存到一个float数组中
+		float vertices[] = new float[vCount * 3];
+		for (int i = 0; i < alVertix.size(); i++) {
+			vertices[i] = alVertix.get(i);
+		}
+
+		//创建顶点坐标数据缓冲
+		//vertices.length*4是因为一个整数四个字节
+		ByteBuffer vbb = ByteBuffer.allocateDirect(vertices.length * 4);
+		vbb.order(ByteOrder.nativeOrder());//设置字节顺序
+		mVertexBuffer = vbb.asFloatBuffer();//转换为int型缓冲
+		mVertexBuffer.put(vertices);//向缓冲区中放入顶点坐标数据
+		mVertexBuffer.position(0);//设置缓冲区起始位置
+		//特别提示：由于不同平台字节顺序不同数据单元不是字节的一定要经过ByteBuffer
+		//转换，关键是要通过ByteOrder设置nativeOrder()，否则有可能会出问题
+		
+		 //将alLongLat中的经纬度值转存到一个float数组中
+        float[] longlat=new float[alLongLat.size()];
+        for(int i=0;i<alLongLat.size();i++)
+        {
+        	longlat[i]=alLongLat.get(i);
+        }
+        ByteBuffer llbb = ByteBuffer.allocateDirect(longlat.length*4);
+        llbb.order(ByteOrder.nativeOrder());//设置字节顺序
+        mLongLatBuffer=llbb.asFloatBuffer();
+        mLongLatBuffer.put(longlat);
+        mLongLatBuffer.position(0);        
+	}
+
+	//初始化着色器
+	public void initShader(MySurfaceView mv) {
+		//加载顶点着色器的脚本内容
+		mVertexShader = ShaderUtil.loadFromAssetsFile("vertex.sh",
+				mv.getResources());
+		//加载片元着色器的脚本内容
+		mFragmentShader = ShaderUtil.loadFromAssetsFile("frag.sh",
+				mv.getResources());
+		//基于顶点着色器与片元着色器创建程序
+		mProgram = ShaderUtil.createProgram(mVertexShader, mFragmentShader);
+		//获取程序中顶点位置属性引用
+		maPositionHandle = GLES20.glGetAttribLocation(mProgram, "aPosition");
+		//获取程序中总变换矩阵引用
+		muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
+		//获取程序中顶点经纬度属性引用
+        maLongLatHandle=GLES20.glGetAttribLocation(mProgram, "aLongLat");
+	}
+
+	public void drawSelf() {
+		
+    	MatrixState.rotate(xAngle, 1, 0, 0);//绕X轴转动
+    	MatrixState.rotate(yAngle, 0, 1, 0);//绕Y轴转动
+    	MatrixState.rotate(zAngle, 0, 0, 1);//绕Z轴转动
+		//制定使用某套着色器程序
+		GLES20.glUseProgram(mProgram);
+		//将最终变换矩阵传入着色器程序
+		GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false,
+				MatrixState.getFinalMatrix(), 0);
+		  
+        //为画笔指定顶点经纬度数据
+        GLES20.glVertexAttribPointer  
+        (
+       		maLongLatHandle,  
+        		2, 
+        		GLES20.GL_FLOAT, 
+        		false,
+               2*4,   
+               mLongLatBuffer
+        );  
+		//将顶点位置数据传入渲染管线
+		GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT,
+				false, 3 * 4, mVertexBuffer);
+		//启用顶点位置、顶点经纬度数据
+		GLES20.glEnableVertexAttribArray(maPositionHandle);
+		GLES20.glEnableVertexAttribArray(maLongLatHandle); 
+		//绘制球		
+		GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, vCount);
+	}
+}

第14章 片元着色器的妙用/Sample14_1/src/com/bn/Sample14_1/Constant.java

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+package com.bn.Sample14_1;
+
+public class Constant 
+{
+	//单位尺寸
+	public static final float UNIT_SIZE=1f;
+	//计算GLSurfaceView的宽高比
+    public static float ratio;
+}

第14章 片元着色器的妙用/Sample14_1/src/com/bn/Sample14_1/MatrixState.java

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+package com.bn.Sample14_1;
+import java.nio.ByteBuffer;
+import android.opengl.Matrix;
+
+//存储系统矩阵状态的类
+public class MatrixState 
+{  
+	private static float[] mProjMatrix = new float[16];//4x4矩阵 投影用
+    private static float[] mVMatrix = new float[16];//摄像机位置朝向9参数矩阵   
+    private static float[] currMatrix;//当前变换矩阵
+      
+    //保护变换矩阵的栈
+    static float[][] mStack=new float[10][16];
+    static int stackTop=-1;
+    
+    public static void setInitStack()//获取不变换初始矩阵
+    {
+    	currMatrix=new float[16];
+    	Matrix.setRotateM(currMatrix, 0, 0, 1, 0, 0);
+    }
+    
+    public static void pushMatrix()//保护变换矩阵
+    {
+    	stackTop++;
+    	for(int i=0;i<16;i++)
+    	{
+    		mStack[stackTop][i]=currMatrix[i];
+    	}
+    }
+    
+    public static void popMatrix()//恢复变换矩阵
+    {
+    	for(int i=0;i<16;i++)
+    	{
+    		currMatrix[i]=mStack[stackTop][i];
+    	}
+    	stackTop--;
+    }
+    
+    public static void translate(float x,float y,float z)//设置沿xyz轴移动
+    {
+    	Matrix.translateM(currMatrix, 0, x, y, z);
+    }
+    
+    public static void rotate(float angle,float x,float y,float z)//设置绕xyz轴移动
+    {
+    	Matrix.rotateM(currMatrix,0,angle,x,y,z);
+    }
+    
+    
+    //设置摄像机
+    static ByteBuffer llbb= ByteBuffer.allocateDirect(3*4);
+    static float[] cameraLocation=new float[3];//摄像机位置
+    public static void setCamera
+    (
+    		float cx,	//摄像机位置x
+    		float cy,   //摄像机位置y
+    		float cz,   //摄像机位置z
+    		float tx,   //摄像机目标点x
+    		float ty,   //摄像机目标点y
+    		float tz,   //摄像机目标点z
+    		float upx,  //摄像机UP向量X分量
+    		float upy,  //摄像机UP向量Y分量
+    		float upz   //摄像机UP向量Z分量		
+    )
+    {
+        	Matrix.setLookAtM
+            (
+            		mVMatrix, 
+            		0, 
+            		cx,
+            		cy,
+            		cz,
+            		tx,
+            		ty,
+            		tz,
+            		upx,
+            		upy,
+            		upz
+            );
+    }
+    
+    //设置透视投影参数
+    public static void setProjectFrustum
+    ( 
+    	float left,		//near面的left
+    	float right,    //near面的right
+    	float bottom,   //near面的bottom
+    	float top,      //near面的top
+    	float near,		//near面距离
+    	float far       //far面距离
+    )
+    {
+    	Matrix.frustumM(mProjMatrix, 0, left, right, bottom, top, near, far);
+    }
+    
+    //设置正交投影参数
+    public static void setProjectOrtho
+    (
+    	float left,		//near面的left
+    	float right,    //near面的right
+    	float bottom,   //near面的bottom
+    	float top,      //near面的top
+    	float near,		//near面距离
+    	float far       //far面距离
+    )
+    {    	
+    	Matrix.orthoM(mProjMatrix, 0, left, right, bottom, top, near, far);
+    }
+    
+    //获取具体物体的总变换矩阵
+    static float[] mMVPMatrix=new float[16];
+    public static float[] getFinalMatrix()
+    {	
+    	Matrix.multiplyMM(mMVPMatrix, 0, mVMatrix, 0, currMatrix, 0);
+        Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mMVPMatrix, 0);        
+        return mMVPMatrix;
+    }
+    
+    //获取具体物体的变换矩阵
+    public static float[] getMMatrix()
+    {       
+        return currMatrix;
+    }
+}

第14章 片元着色器的妙用/Sample14_1/src/com/bn/Sample14_1/MySurfaceView.java

@@ -0,0 +1,82 @@
+package com.bn.Sample14_1;
+import javax.microedition.khronos.egl.EGLConfig;
+import javax.microedition.khronos.opengles.GL10;
+import android.content.Context;
+import android.opengl.GLES20;
+import android.opengl.GLSurfaceView;
+import android.view.MotionEvent;
+
+class MySurfaceView extends GLSurfaceView 
+{
+	private final float TOUCH_SCALE_FACTOR = 180.0f/320;//角度缩放比例
+    private SceneRenderer mRenderer;//场景渲染器	   
+	Ball ball;//球
+	
+	private float mPreviousY;//上次的触控位置Y坐标
+    private float mPreviousX;//上次的触控位置X坐标
+	public MySurfaceView(Context context) {
+        super(context);
+        this.setEGLContextClientVersion(2); //设置使用OPENGL ES2.0
+        mRenderer = new SceneRenderer();	//创建场景渲染器
+        setRenderer(mRenderer);				//设置渲染器		        
+        setRenderMode(GLSurfaceView.RENDERMODE_CONTINUOUSLY);//设置渲染模式为主动渲染   
+    }
+	//触摸事件回调方法
+    @Override 
+    public boolean onTouchEvent(MotionEvent e) {
+        float y = e.getY();
+        float x = e.getX();
+        switch (e.getAction()) {
+        case MotionEvent.ACTION_MOVE:
+            float dy = y - mPreviousY;//计算触控笔Y位移
+            float dx = x - mPreviousX;//计算触控笔X位移 
+            ball.yAngle += dx * TOUCH_SCALE_FACTOR;//设置填充椭圆绕y轴旋转的角度
+            ball.xAngle+= dy * TOUCH_SCALE_FACTOR;//设置填充椭圆绕x轴旋转的角度
+        }
+        mPreviousY = y;//记录触控笔位置
+        mPreviousX = x;//记录触控笔位置
+        return true;
+    }
+	private class SceneRenderer implements GLSurfaceView.Renderer 
+    {
+    	
+        public void onDrawFrame(GL10 gl) 
+        { 
+        	//清除深度缓冲与颜色缓冲
+            GLES20.glClear( GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);
+            //保护现场
+            MatrixState.pushMatrix(); 
+            //绘制球
+            MatrixState.pushMatrix();
+            ball.drawSelf();    
+            MatrixState.popMatrix();       
+            //恢复现场
+            MatrixState.popMatrix();
+        }  
+
+        public void onSurfaceChanged(GL10 gl, int width, int height) {
+            //设置视窗大小及位置 
+        	GLES20.glViewport(0, 0, width, height); 
+        	//计算GLSurfaceView的宽高比
+            Constant.ratio = (float) width / height;
+			// 调用此方法计算产生透视投影矩阵
+            MatrixState.setProjectFrustum(-Constant.ratio, Constant.ratio, -1, 1, 20, 100);
+			// 调用此方法产生摄像机9参数位置矩阵
+			MatrixState.setCamera(0, 0, 30, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
+            
+            //初始化变换矩阵
+            MatrixState.setInitStack();
+        }
+
+        public void onSurfaceCreated(GL10 gl, EGLConfig config) {
+            //设置屏幕背景色RGBA
+            GLES20.glClearColor(0f,0f,0f, 1.0f);  
+            //创建球对象
+            ball=new Ball(MySurfaceView.this);
+            //打开深度检测
+            GLES20.glEnable(GLES20.GL_DEPTH_TEST);
+            //打开背面剪裁   
+            GLES20.glEnable(GLES20.GL_CULL_FACE);
+        }
+    }
+}

第14章 片元着色器的妙用/Sample14_1/src/com/bn/Sample14_1/Sample14_1_Activity.java

@@ -0,0 +1,33 @@
+package com.bn.Sample14_1;
+import android.app.Activity;
+import android.os.Bundle;
+import android.view.Window;
+import android.view.WindowManager;
+
+public class Sample14_1_Activity extends Activity {
+	private MySurfaceView mGLSurfaceView;
+    @Override
+	protected void onCreate(Bundle savedInstanceState) {
+		super.onCreate(savedInstanceState);
+		// 设置为全屏
+		requestWindowFeature(Window.FEATURE_NO_TITLE);
+		getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
+				WindowManager.LayoutParams.FLAG_FULLSCREEN);
+		// 初始化GLSurfaceView
+		mGLSurfaceView = new MySurfaceView(this);
+		// 切换到主界面
+		setContentView(mGLSurfaceView);	
+	}
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        mGLSurfaceView.onResume();
+    }
+
+    @Override
+    protected void onPause() {
+        super.onPause();
+        mGLSurfaceView.onPause(); 
+    } 
+}

第14章 片元着色器的妙用/Sample14_1/src/com/bn/Sample14_1/ShaderUtil.java

@@ -0,0 +1,126 @@
+package com.bn.Sample14_1;
+
+import java.io.ByteArrayOutputStream;
+import java.io.InputStream;
+
+import android.content.res.Resources;
+import android.opengl.GLES20;
+import android.util.Log;
+
+//加载顶点Shader与片元Shader的工具类
+public class ShaderUtil 
+{
+   //加载制定shader的方法
+   public static int loadShader
+   (
+		 int shaderType, //shader的类型  GLES20.GL_VERTEX_SHADER   GLES20.GL_FRAGMENT_SHADER
+		 String source   //shader的脚本字符串
+   ) 
+   {
+	    //创建一个新shader
+        int shader = GLES20.glCreateShader(shaderType);
+        //若创建成功则加载shader
+        if (shader != 0) 
+        {
+        	//加载shader的源代码
+            GLES20.glShaderSource(shader, source);
+            //编译shader
+            GLES20.glCompileShader(shader);
+            //存放编译成功shader数量的数组
+            int[] compiled = new int[1];
+            //获取Shader的编译情况
+            GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
+            if (compiled[0] == 0) 
+            {//若编译失败则显示错误日志并删除此shader
+                Log.e("ES20_ERROR", "Could not compile shader " + shaderType + ":");
+                Log.e("ES20_ERROR", GLES20.glGetShaderInfoLog(shader));
+                GLES20.glDeleteShader(shader);
+                shader = 0;      
+            }  
+        }
+        return shader;
+    }
+    
+   //创建shader程序的方法
+   public static int createProgram(String vertexSource, String fragmentSource) 
+   {
+	    //加载顶点着色器
+        int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
+        if (vertexShader == 0) 
+        {
+            return 0;
+        }
+        
+        //加载片元着色器
+        int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
+        if (pixelShader == 0) 
+        {
+            return 0;
+        }
+
+        //创建程序
+        int program = GLES20.glCreateProgram();
+        //若程序创建成功则向程序中加入顶点着色器与片元着色器
+        if (program != 0) 
+        {
+        	//向程序中加入顶点着色器
+            GLES20.glAttachShader(program, vertexShader);
+            checkGlError("glAttachShader");
+            //向程序中加入片元着色器
+            GLES20.glAttachShader(program, pixelShader);
+            checkGlError("glAttachShader");
+            //链接程序
+            GLES20.glLinkProgram(program);
+            //存放链接成功program数量的数组
+            int[] linkStatus = new int[1];
+            //获取program的链接情况
+            GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
+            //若链接失败则报错并删除程序
+            if (linkStatus[0] != GLES20.GL_TRUE) 
+            {
+                Log.e("ES20_ERROR", "Could not link program: ");
+                Log.e("ES20_ERROR", GLES20.glGetProgramInfoLog(program));
+                GLES20.glDeleteProgram(program);
+                program = 0;
+            }
+        }
+        return program;
+    }
+    
+   //检查每一步操作是否有错误的方法 
+   public static void checkGlError(String op) 
+   {
+        int error;
+        while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) 
+        {
+            Log.e("ES20_ERROR", op + ": glError " + error);
+            throw new RuntimeException(op + ": glError " + error);
+        }
+   }
+   
+   //从sh脚本中加载shader内容的方法
+   public static String loadFromAssetsFile(String fname,Resources r)
+   {
+   	String result=null;    	
+   	try
+   	{
+   		InputStream in=r.getAssets().open(fname);
+			int ch=0;
+		    ByteArrayOutputStream baos = new ByteArrayOutputStream();
+		    while((ch=in.read())!=-1)
+		    {
+		      	baos.write(ch);
+		    }      
+		    byte[] buff=baos.toByteArray();
+		    baos.close();
+		    in.close();
+   		result=new String(buff,"UTF-8"); 
+   		result=result.replaceAll("\\r\\n","\n");
+   	}
+   	catch(Exception e)
+   	{
+   		e.printStackTrace();
+   	}   
+   	return result;
+   }
+}