在Android应用中实现3D圆柱体

总共三个类

    package wyf.lgz;                import java.nio.ByteBuffer;        import java.nio.ByteOrder;        import java.nio.FloatBuffer;        import java.util.ArrayList;                import javax.microedition.khronos.opengles.GL10;                public class DrawCylinder        {            private FloatBuffer myVertexBuffer;//顶点坐标缓冲             private FloatBuffer myNormalBuffer;//法向量缓冲            private FloatBuffer myTexture;//纹理缓冲                        int textureId;                        int vCount;//顶点数量                        float length;//圆柱长度            float circle_radius;//圆截环半径            float degreespan;  //圆截环每一份的度数大小                        public float mAngleX;            public float mAngleY;            public float mAngleZ;                        public DrawCylinder(float length,float circle_radius,float degreespan,int textureId)            {                this.circle_radius=circle_radius;                this.length=length;                this.degreespan=degreespan;                this.textureId=textureId;                                float collength=(float)length;//圆柱每块所占的长度                int spannum=(int)(360.0f/degreespan);                                ArrayList<Float> val=new ArrayList<Float>();//顶点存放列表                ArrayList<Float> ial=new ArrayList<Float>();//法向量存放列表                                for(float circle_degree=180.0f;circle_degree>0.0f;circle_degree-=degreespan)//循环行                {                        float x1 =(float)(-length/2);                        float y1=(float) (circle_radius*Math.sin(Math.toRadians(circle_degree)));                        float z1=(float) (circle_radius*Math.cos(Math.toRadians(circle_degree)));                                                float a1=0;                        float b1=y1;                        float c1=z1;                        float l1=getVectorLength(a1, b1, c1);//模长                        a1=a1/l1;//法向量规格化                        b1=b1/l1;                        c1=c1/l1;                                                float x2 =(float)(-length/2);                        float y2=(float) (circle_radius*Math.sin(Math.toRadians(circle_degree-degreespan)));                        float z2=(float) (circle_radius*Math.cos(Math.toRadians(circle_degree-degreespan)));                                                float a2=0;                        float b2=y2;                        float c2=z2;                        float l2=getVectorLength(a2, b2, c2);//模长                        a2=a2/l2;//法向量规格化                        b2=b2/l2;                        c2=c2/l2;                                                float x3 =(float)(length/2);                        float y3=(float) (circle_radius*Math.sin(Math.toRadians(circle_degree-degreespan)));                        float z3=(float) (circle_radius*Math.cos(Math.toRadians(circle_degree-degreespan)));                                                float a3=0;                        float b3=y3;                        float c3=z3;                        float l3=getVectorLength(a3, b3, c3);//模长                        a3=a3/l3;//法向量规格化                        b3=b3/l3;                        c3=c3/l3;                                                float x4 =(float)(length/2);                        float y4=(float) (circle_radius*Math.sin(Math.toRadians(circle_degree)));                        float z4=(float) (circle_radius*Math.cos(Math.toRadians(circle_degree)));                                                float a4=0;                        float b4=y4;                        float c4=z4;                        float l4=getVectorLength(a4, b4, c4);//模长                        a4=a4/l4;//法向量规格化                        b4=b4/l4;                        c4=c4/l4;                                                val.add(x1);val.add(y1);val.add(z1);//两个三角形，共6个顶点的坐标                        val.add(x2);val.add(y2);val.add(z2);                        val.add(x4);val.add(y4);val.add(z4);                                                val.add(x2);val.add(y2);val.add(z2);                        val.add(x3);val.add(y3);val.add(z3);                        val.add(x4);val.add(y4);val.add(z4);                                                ial.add(a1);ial.add(b1);ial.add(c1);//顶点对应的法向量                        ial.add(a2);ial.add(b2);ial.add(c2);                        ial.add(a4);ial.add(b4);ial.add(c4);                                                ial.add(a2);ial.add(b2);ial.add(c2);                        ial.add(a3);ial.add(b3);ial.add(c3);                        ial.add(a4);ial.add(b4);ial.add(c4);                }                                 vCount=val.size()/3;//确定顶点数量                                //顶点                float[] vertexs=new float[vCount*3];                for(int i=0;i<vCount*3;i++)                {                    vertexs[i]=val.get(i);                }                ByteBuffer vbb=ByteBuffer.allocateDirect(vertexs.length*4);                vbb.order(ByteOrder.nativeOrder());                myVertexBuffer=vbb.asFloatBuffer();                myVertexBuffer.put(vertexs);                myVertexBuffer.position(0);                                //法向量                float[] normals=new float[vCount*3];                for(int i=0;i<vCount*3;i++)                {                    normals[i]=ial.get(i);                }                ByteBuffer ibb=ByteBuffer.allocateDirect(normals.length*4);                ibb.order(ByteOrder.nativeOrder());                myNormalBuffer=ibb.asFloatBuffer();                myNormalBuffer.put(normals);                myNormalBuffer.position(0);                                //纹理                float[] textures=generateTexCoor(spannum);                ByteBuffer tbb=ByteBuffer.allocateDirect(textures.length*4);                tbb.order(ByteOrder.nativeOrder());                myTexture=tbb.asFloatBuffer();                myTexture.put(textures);                myTexture.position(0);            }                        public void drawSelf(GL10 gl)            {                gl.glRotatef(mAngleX, 1, 0, 0);//旋转                gl.glRotatef(mAngleY, 0, 1, 0);                gl.glRotatef(mAngleZ, 0, 0, 1);                                gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);//打开顶点缓冲                gl.glVertexPointer(3, GL10.GL_FLOAT, 0, myVertexBuffer);//指定顶点缓冲                                gl.glEnableClientState(GL10.GL_NORMAL_ARRAY);//打开法向量缓冲                gl.glNormalPointer(GL10.GL_FLOAT, 0, myNormalBuffer);//指定法向量缓冲                                gl.glEnable(GL10.GL_TEXTURE_2D);                gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);                gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, myTexture);                gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);                                gl.glDrawArrays(GL10.GL_TRIANGLES, 0, vCount);//绘制图像                                gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);//关闭缓冲                gl.glEnable(GL10.GL_TEXTURE_2D);                gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);                gl.glDisableClientState(GL10.GL_NORMAL_ARRAY);            }                        //法向量规格化，求模长度            public float getVectorLength(float x,float y,float z)            {                float pingfang=x*x+y*y+z*z;                float length=(float) Math.sqrt(pingfang);                return length;            }                        //自动切分纹理产生纹理数组的方法            public float[] generateTexCoor(int bh)            {                float[] result=new float[bh*6*2];                 float REPEAT=2;                float sizeh=1.0f/bh;//行数                int c=0;                for(int i=0;i<bh;i++)                {                        //每行列一个矩形，由两个三角形构成，共六个点，12个纹理坐标                        float t=i*sizeh;                                                result[c++]=0;                        result[c++]=t;                                            result[c++]=0;                        result[c++]=t+sizeh;                                                 result[c++]=REPEAT;                        result[c++]=t;                                                            result[c++]=0;                        result[c++]=t+sizeh;                                                result[c++]=REPEAT;                        result[c++]=t+sizeh;                                                   result[c++]=REPEAT;                        result[c++]=t;                }                return result;            }        }  

    package wyf.lgz;                import android.app.Activity;        import android.content.pm.ActivityInfo;        import android.os.Bundle;        import android.view.Window;        import android.view.WindowManager;                public class Activity_GL_Cylinder extends Activity {            private MyGLSurfaceView mGLSurfaceView;            /** Called when the activity is first created. */            @Override            public void onCreate(Bundle savedInstanceState) {                super.onCreate(savedInstanceState);                                requestWindowFeature(Window.FEATURE_NO_TITLE);                getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);                setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);                                mGLSurfaceView = new MyGLSurfaceView(this);                setContentView(mGLSurfaceView);                mGLSurfaceView.setFocusableInTouchMode(true);//设置为可触控                mGLSurfaceView.requestFocus();//获取焦点            }                        @Override            protected void onResume() {                super.onResume();                mGLSurfaceView.onResume();            }                    @Override            protected void onPause() {                super.onPause();                mGLSurfaceView.onPause();            }           }  

    package wyf.lgz;                import java.io.IOException;        import java.io.InputStream;                import android.opengl.GLSurfaceView;        import android.opengl.GLUtils;                import javax.microedition.khronos.egl.EGLConfig;        import javax.microedition.khronos.opengles.GL10;        import javax.microedition.khronos.opengles.GL11;                import android.content.Context;        import android.graphics.Bitmap;        import android.graphics.BitmapFactory;        import android.view.MotionEvent;                public class MyGLSurfaceView 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            private float mPreviousY;//上次的触控位置Y坐标            private float mPreviousX;//上次的触控位置Y坐标            private int lightAngle=90;//灯的当前角度                        public MyGLSurfaceView(Context context) {                super(context);                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Y位移                    mRenderer.cylinder.mAngleX += dy * TOUCH_SCALE_FACTOR;//设置沿x轴旋转角度                    mRenderer.cylinder.mAngleZ += dx * TOUCH_SCALE_FACTOR;//设置沿z轴旋转角度                    requestRender();//重绘画面                }                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             {                   int textureId;//纹理名称ID                DrawCylinder cylinder;//创建圆柱体                                public SceneRenderer()                {                        }                                public void onDrawFrame(GL10 gl) {                                      //清除颜色缓存                    gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);                    //设置当前矩阵为模式矩阵                    gl.glMatrixMode(GL10.GL_MODELVIEW);                    //设置当前矩阵为单位矩阵                    gl.glLoadIdentity();                                                   gl.glPushMatrix();//保护变换矩阵现场                                        float lx=0; //设定光源的位置                    float ly=(float)(7*Math.cos(Math.toRadians(lightAngle)));                    float lz=(float)(7*Math.sin(Math.toRadians(lightAngle)));                    float[] positionParamsRed={lx,ly,lz,0};                    gl.glLightfv(GL10.GL_LIGHT1, GL10.GL_POSITION, positionParamsRed,0);                                            initMaterial(gl);//初始化纹理                    gl.glTranslatef(0, 0, -10f);//平移                    initLight(gl);//开灯                    cylinder.drawSelf(gl);//绘制                    closeLight(gl);//关灯                                        gl.glPopMatrix();//恢复变换矩阵现场                }                        public void onSurfaceChanged(GL10 gl, int width, int height) {                    //设置视窗大小及位置                     gl.glViewport(0, 0, width, height);                    //设置当前矩阵为投影矩阵                    gl.glMatrixMode(GL10.GL_PROJECTION);                    //设置当前矩阵为单位矩阵                    gl.glLoadIdentity();                    //计算透视投影的比例                    float ratio = (float) width / height;                    //调用此方法计算产生透视投影矩阵                    gl.glFrustumf(-ratio, ratio, -1, 1, 1, 100);                }                        public void onSurfaceCreated(GL10 gl, EGLConfig config) {                    //关闭抗抖动                     gl.glDisable(GL10.GL_DITHER);                    //设置特定Hint项目的模式，这里为设置为使用快速模式                    gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT,GL10.GL_FASTEST);                    //设置屏幕背景色黑色RGBA                    gl.glClearColor(0,0,0,0);                    //设置着色模型为平滑着色                       gl.glShadeModel(GL10.GL_SMOOTH);                    //启用深度测试                    gl.glEnable(GL10.GL_DEPTH_TEST);                                         textureId=initTexture(gl,R.drawable.stone);//纹理ID                    cylinder=new DrawCylinder(10f,2f,18f,textureId);//创建圆柱体                            //            //开启一个线程自动旋转光源        //            new Thread()        //            {        //                public void run()        //                {        //                    while(true)        //                    {        //                      lightAngle+=5;//转动灯        //                      mRenderer.cylinder.mAngleY+=2*TOUCH_SCALE_FACTOR;//球沿Y轴转动        //                    requestRender();//重绘画面        //                    try        //                    {        //                        Thread.sleep(50);//休息10ms再重绘        //                    }        //                    catch(Exception e)        //                    {        //                        e.printStackTrace();        //                    }                           //                    }        //                }        //            }.start();                }            }                        //初始化白色灯            private void initLight(GL10 gl)            {                    gl.glEnable(GL10.GL_LIGHTING);//允许光照                    gl.glEnable(GL10.GL_LIGHT1);//打开1号灯                                  //环境光设置                float[] ambientParams={0.2f,0.2f,0.2f,1.0f};//光参数 RGBA                gl.glLightfv(GL10.GL_LIGHT1, GL10.GL_AMBIENT, ambientParams,0);                                            //散射光设置                float[] diffuseParams={1f,1f,1f,1.0f};//光参数 RGBA                gl.glLightfv(GL10.GL_LIGHT1, GL10.GL_DIFFUSE, diffuseParams,0);                                 //反射光设置                float[] specularParams={1f,1f,1f,1.0f};//光参数 RGBA                gl.glLightfv(GL10.GL_LIGHT1, GL10.GL_SPECULAR, specularParams,0);             }                        //关闭灯            private void closeLight(GL10 gl)            {                gl.glDisable(GL10.GL_LIGHT1);                gl.glDisable(GL10.GL_LIGHTING);            }                        //初始化材质            private void initMaterial(GL10 gl)            {                //环境光                float ambientMaterial[] = {248f/255f, 242f/255f, 144f/255f, 1.0f};                gl.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_AMBIENT, ambientMaterial,0);                //散射光                float diffuseMaterial[] = {248f/255f, 242f/255f, 144f/255f, 1.0f};                gl.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_DIFFUSE, diffuseMaterial,0);                //高光材质                float specularMaterial[] = {248f/255f, 242f/255f, 144f/255f, 1.0f};                gl.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_SPECULAR, specularMaterial,0);                gl.glMaterialf(GL10.GL_FRONT_AND_BACK, GL10.GL_SHININESS, 100.0f);            }                        //初始化纹理            public int initTexture(GL10 gl,int drawableId)//textureId            {                //生成纹理ID                int[] textures = new int[1];                gl.glGenTextures(1, textures, 0);                    int currTextureId=textures[0];                    gl.glBindTexture(GL10.GL_TEXTURE_2D, currTextureId);                gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER,GL10.GL_LINEAR_MIPMAP_NEAREST);                gl.glTexParameterf(GL10.GL_TEXTURE_2D,GL10.GL_TEXTURE_MAG_FILTER,GL10.GL_LINEAR_MIPMAP_LINEAR);                ((GL11)gl).glTexParameterf(GL10.GL_TEXTURE_2D, GL11.GL_GENERATE_MIPMAP, GL10.GL_TRUE);                gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S,GL10.GL_REPEAT);                gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T,GL10.GL_REPEAT);                                                                InputStream is = this.getResources().openRawResource(drawableId);                Bitmap bitmapTmp;                 try                 {                    bitmapTmp = BitmapFactory.decodeStream(is);                }                 finally                 {                    try                     {                        is.close();                    }                     catch(IOException e)                     {                        e.printStackTrace();                    }                }                GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmapTmp, 0);                bitmapTmp.recycle();                                 return currTextureId;            }        }