纹理不适用于网格 - OpenGL

我正在使用 OpenGL Es。我已成功加载 obj 文件（网格）并且显示良好，但当我应用纹理时，它不显示。

我添加了下面的代码。

public void draw(GL10 gl) {
    // bind the previously generated texture
    gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
    gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
    gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
    // Set the face rotation
    gl.glFrontFace(GL10.GL_CW);

    gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
    gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);

    //Disable the client state before leaving
    gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);

    for(int i=0; i<parts.size(); i++){
        TDModelPart t=parts.get(i);
        gl.glNormalPointer(GL10.GL_FLOAT, 0, t.getNormalBuffer());
        gl.glDrawElements(GL10.GL_TRIANGLES,t.getFacesCount(),GL10.GL_UNSIGNED_SHORT,t.getFaceBuffer());
        gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
    }
}

public void buildVertexBuffer(){
    ByteBuffer vBuf = ByteBuffer.allocateDirect(v.size() * 4);
    vBuf.order(ByteOrder.nativeOrder());
    vertexBuffer = vBuf.asFloatBuffer();
    vertexBuffer.put(toPrimitiveArrayF(v));
    vertexBuffer.position(0);

    vBuf = ByteBuffer.allocateDirect(texture.length * 4);
    vBuf.order(ByteOrder.nativeOrder());
    textureBuffer = vBuf.asFloatBuffer();
    textureBuffer.put(texture);
    textureBuffer.position(0);
}

private static float[] toPrimitiveArrayF(Vector<Float> vector){
    float[] f;
    f=new float[vector.size()];
    for (int i=0; i<vector.size(); i++){
        f[i]=vector.get(i);
    }
    return f;
}

/**
 * Load the texture for the square
 * @param gl
 * @param context
 */
public void loadGLTexture(GL10 gl, Context context) {
    // loading texture
    Bitmap bitmap = BitmapFactory.decodeResource(context.getResources(),
            R.drawable.nehe);

    // generate one texture pointer
    gl.glGenTextures(1, textures, 0);
    // ...and bind it to our array
    gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);

    // create nearest filtered texture
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);

    //Different possible texture parameters, e.g. GL10.GL_CLAMP_TO_EDGE
    //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);

    // Use Android GLUtils to specify a two-dimensional texture image from our bitmap 
    GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);

    // Clean up
    bitmap.recycle();
}

public void onSurfaceCreated(GL10 gl, EGLConfig config) {
    gl.glLightfv(GL10.GL_LIGHT0, GL10.GL_AMBIENT, lightAmbientBuffer);      
    gl.glLightfv(GL10.GL_LIGHT0, GL10.GL_DIFFUSE, lightDiffuseBuffer);      
    gl.glLightfv(GL10.GL_LIGHT0, GL10.GL_POSITION, lightPositionBuffer);    
    gl.glEnable(GL10.GL_LIGHT0);

    model.loadGLTexture(gl, context);
    gl.glEnable(GL10.GL_TEXTURE_2D);
    gl.glShadeModel(GL10.GL_SMOOTH);            
    gl.glClearColor(0.0f, 0.0f, 0.0f, 0.5f);    
    gl.glClearDepthf(1.0f);                     
    gl.glEnable(GL10.GL_DEPTH_TEST);            
    gl.glDepthFunc(GL10.GL_LEQUAL);         

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

//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);

for(int i=0; i<parts.size(); i++) {
    TDModelPart t=parts.get(i);
    gl.glNormalPointer(GL10.GL_FLOAT, 0, t.getNormalBuffer());
    gl.glDrawElements(GL10.GL_TRIANGLES,t.getFacesCount(),GL10.GL_UNSIGNED_SHORT,t.getFaceBuffer());
    gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
}

当然禁用 texCoord 数组before绘制任何东西都不是一个好主意，因为这将导致您的对象没有任何有效的纹理坐标（严格来说，它的所有顶点都具有当前的默认纹理坐标）。同样，您不应该禁用GL_VERTEX_ARRAY在循环结束时，因为这将使您的对象对于所有后续循环迭代没有任何有效的位置数据。所以你的代码可能应该是这样的：

// bind the previously generated texture
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// Set the face rotation
gl.glFrontFace(GL10.GL_CW);

gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);

for(int i=0; i<parts.size(); i++){
    TDModelPart t=parts.get(i);
    gl.glNormalPointer(GL10.GL_FLOAT, 0, t.getNormalBuffer());
    gl.glDrawElements(GL10.GL_TRIANGLES,t.getFacesCount(),GL10.GL_UNSIGNED_SHORT,t.getFaceBuffer());
}

//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);

（现在我会忽略你设置的glNormalPointer虽然没有启用GL_NORMAL_ARRAY.)

请始终记住，OpenGL 是一个状态机，所有操作（尤其是绘制调用）都在调用它们时对当前状态进行操作，并且该状态永远不会改变，除非you更改yourself (with "you"指此处的应用程序代码，包括使用相同 OpenGL 上下文的任何其他第三方组件）。