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OPhone与OpenGL ES绘制3D图形（三）应用举例以下内容给出一个Ophone上绘制一个3D球形的程序。主要的绘制程序： static private FloatBuffer vertex;//顶点对应的字节缓冲 static private FloatBuffer normal;//法向量对应的字节缓冲 float[] lightPos = new float[] {10.0f, 10.0f, 10.0f, 1.0f };//光源的坐标 private static final int STEP = 24; private static final float RADIUS = 1.0f;//半径 protected void init(GL10 gl) { gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);//设置背景颜色 gl.glLightfv(GL10.GL_LIGHT0, GL10.GL_POSITION, lightPos, 0); gl.glEnable(GL10.GL_LIGHTING);//启用光照 gl.glEnable(GL10.GL_LIGHT0); //打开光源 gl.glClearDepthf(1.0f);//设置深度缓存 gl.glDepthFunc(GL10.GL_LEQUAL);//设置深度缓存比较函数，GL_LEQUAL表示新的像素的//深度缓存值小于等于当前像素的深度缓存值时通过深度测试 gl.glEnable(GL10.GL_DEPTH_TEST);//启用深度缓存 gl.glEnable(GL10.GL_CULL_FACE); gl.glShadeModel(GL10.GL_SMOOTH);//设置阴影模式GL_SMOOTH } protected void drawFrame(GL10 gl) { gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT); gl.glMatrixMode(GL10.GL_MODELVIEW); gl.glLoadIdentity(); GLU.gluLookAt(gl, 0, 0, 7f, 0f, 0f, 0f, 0f, 1.0f, 0.0f); drawSphere(gl, RADIUS, STEP, STEP); //绘制球形 } public static void gluLookAt (GL10 gl, float eyeX, float eyeY, float eyeZ, float centerX, float centerY, float centerZ, float upX, float upY, float upZ); 它共接受三组坐标，分别为eye、 center和up。eye表示我们眼睛在"世界坐标系"中的位置，center表示眼睛"看"的那个点的坐标，up坐标表示观察者本身的方向,如果将观察点比喻成我们的眼睛，那么这个up则表示我们是正立还是倒立异或某一个角度在看，这里是正立方式，所以是{0，1，0}。 private static void drawSphere(GL10 gl, float radius, int stacks, int slices) { vertex=allocateFloatBuffer( 4* 6 * stacks * (slices+1) ); normal=allocateFloatBuffer( 4* 6 * stacks * (slices+1) ); int i, j, triangles; float slicestep, stackstep; stackstep = ((float)Math.PI) / stacks; slicestep = 2.0f * ((float)Math.PI) / slices; for (i = 0; i < stacks; ++i) { float a = i * stackstep; float b = a + stackstep; float s0 =(float)Math.sin(a); float s1 = (float)Math.sin(b); float c0 = (float)Math.cos(a); float c1 = (float)Math.cos(b); float nv; for (j = 0; j <= slices; ++j) { float c = j * slicestep; float x = (float)Math.cos(c); float y = (float)Math.sin(c); nv=x * s0; normal.put(nv); vertex.put( nv * radius); nv=y * s0; normal.put(nv); vertex.put( nv * radius); nv=c0; normal.put(nv); vertex.put( nv * radius); nv=x * s1; normal.put(nv); vertex.put( nv * radius); nv=y * s1; normal.put(nv); vertex.put( nv * radius); nv=c1; normal.put(nv); vertex.put( nv * radius); } } normal.position(0); vertex.position(0); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertex); gl.glNormalPointer(GL10.GL_FLOAT, 0, normal); gl.glEnableClientState (GL10.GL_VERTEX_ARRAY); gl.glEnableClientState (GL10.GL_NORMAL_ARRAY); triangles = (slices + 1) * 2; for(i = 0; i < stacks; i++) gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, i * triangles, triangles); gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); gl.glDisableClientState(GL10.GL_NORMAL_ARRAY); } private static FloatBuffer allocateFloatBuffer(int capacity){ ByteBuffer vbb = ByteBuffer.allocateDirect(capacity); vbb.order(ByteOrder.nativeOrder()); return vbb.asFloatBuffer(); }

OPhone与OpenGL ES绘制3D图形 （三）

OPhone与OpenGL ES绘制3D图形（三）