紋理的3D球體（找不到幫助我的帖子）

Question

我想創建一個3D球體，我目前有一個球體做成的點雖然我需要應用紋理到這，這是我的問題。

產生球體的代碼如下所示：

public Sphere(float radius, double step) { 


    this.mRaduis = radius; 
    this.mStep = step; 
    sphereVertex = ByteBuffer.allocateDirect(400000) 
      .order(ByteOrder.nativeOrder()).asFloatBuffer(); 
    mPoints = build(); 
    Log.d("ALIS CHECK!!!!!", " COUNT:" + mPoints); 

} 

    public void draw(GL10 gl) { 
    gl.glFrontFace(GL10.GL_CW); 
    gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); 
    gl.glVertexPointer(3, GL10.GL_FLOAT, 0, sphereVertex); 

    gl.glEnable(GL10.GL_TEXTURE_2D); // workaround bug 3623 
    gl.glTexCoordPointer(2, GL10.GL_FIXED, 0, sphereVertex); 

    gl.glColor4f(1.0f, 0.0f, 0.0f, 1.0f); 
    gl.glDrawArrays(GL10.GL_POINTS, 0, mPoints); 
    gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); 
} 


private int build() { 


    double dTheta = mStep * DEG; 
    double dPhi = dTheta; 
    int points = 0; 

    for (double phi = -(Math.PI); phi <= Math.PI; phi += dPhi) { 
     // for each stage calculating the slices 
     for (double theta = 0.0; theta <= (Math.PI * 2); theta += dTheta) { 
      sphereVertex.put((float) (mRaduis * Math.sin(phi) * Math 
        .cos(theta))); //y-coord 
      sphereVertex.put((float) (mRaduis * Math.sin(phi) * Math 
        .sin(theta))); //z 
      sphereVertex.put((float) (mRaduis * Math.cos(phi))); //x 
      points++; 

     } 
    } 

，並在我的渲染類，它看起來是這樣的：

public SphereRenderer(Context context) { 

    mSphere = new Sphere(1, 25); 

    this.context = context; 

    vibrator = SphereActivity.getVibrator(); 
    sphereActivity = SphereActivity.getInstance(); 



} 

public void onSurfaceCreated(GL10 gl, EGLConfig config) { 

    gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f); 

    gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY); 
    gl.glEnable(GL10.GL_TEXTURE_2D); 
    Sphere.loadTexture(gl, context, R.drawable.android); 

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

} 

public void onDrawFrame(GL10 gl) { 

    gl.glClear(GL10.GL_COLOR_BUFFER_BIT); 
    gl.glLoadIdentity(); 


    gl.glTranslatef(0.0f, 0.0f, -4.0f); 

    rotateSphere(gl, startTime); 


    // gl.glRotatef(xRot, 0.0f, 1.0f, 0.0f); 
    // gl.glRotatef(yRot, 1.0f, 0.0f, 0.0f); 
    mSphere.draw(gl); 

    numFrames++; 
    long fpsElapsed = System.currentTimeMillis() - fpsStartTime; 
    if (fpsElapsed > 5 * 1000) { // every 5 seconds 
     float fps = (numFrames * 1000.0F)/fpsElapsed; 
     Log.d("FPS", "Frames per second: " + fps + " (" + numFrames 
       + " frames in " + fpsElapsed + " ms)"); 
     fpsStartTime = System.currentTimeMillis(); 
     numFrames = 0; 
    } 
} 

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

    startTime = System.currentTimeMillis(); 
    fpsStartTime = startTime; 
    numFrames = 0; 
    if (height == 0) { 
     height = 1; 
    } 

    gl.glViewport(0, 0, width, height); 
    gl.glMatrixMode(GL10.GL_PROJECTION); 
    gl.glLoadIdentity(); 

    // Calculate The Aspect Ratio Of The Window 
    GLU.gluPerspective(gl, 45.0f, (float) width/(float) height, 0.1f, 
      100.0f); 

    gl.glMatrixMode(GL10.GL_MODELVIEW); // Select The Modelview Matrix 
    gl.glLoadIdentity(); // Reset The Modelview Matrix 
} 

我非常感謝所有幫助我能！

Answer 1

雖然你可以理論上紋理點，紋理的一個像素意味着你需要很多點來創建一個可識別的地圖。從我可以告訴你需要將你的球體繪製成一組三角形來代替，然後你就可以應用紋理。實際上，這意味着只需合併要創建人臉的點。而不是GL_POINTS你可能想看看使用GL_TRIANGLES - 請參閱OpenGL programming guide on points lines and polygons的正確解釋。