陀螺仪操作摄相机，可以旋转，但角度（轴）还不对

不容易啊，搞了好几天，几乎重看了一遍，3d数学基础，写的不对的一定得指出来哦， 原贴地址:http://blog.youkuaiyun.com/wzq9706/article/details/7415846

可以旋转，但角度（轴）还不对（x轴除外）

-(void)update:(ccTime)time {
    
    CCCamera *cam = [self camera];
    
    if (nil == cam) {
        NSLog(@"Call Camera faild!");
        return;
    }
    
    Document* doc = [Document sharedDocument];
    
    kmVec3 center = {0, 0, -1}; 
    kmVec3 eye = {0, 0, 0};
    kmVec3 up = {0, 1, 0};
    
    //kmVec3Subtract(¢er, &eye, ¢er);
    
    // 得到陀螺仪数据
    float yaw = (float)(CC_RADIANS_TO_DEGREES(doc.motionManager.deviceMotion.attitude.yaw));
    float pitch = (float)(CC_RADIANS_TO_DEGREES(doc.motionManager.deviceMotion.attitude.pitch));
    float roll = (float)(CC_RADIANS_TO_DEGREES(doc.motionManager.deviceMotion.attitude.roll));
    
    // 构建摄相机矩阵
    kmMat4 camMat;
    kmMat4Identity(&camMat);
    
    // 构建旋转矩阵
    kmQuaternion vec4;
    kmMat4 rotaMat;
    kmQuaternionRotationYawPitchRoll(&vec4, yaw, pitch, roll);
    kmMat4RotationQuaternion(&rotaMat, &vec4);
    
    // 构建平移矩阵
    kmMat4 transMat;
    kmMat4Translation(&transMat, 0, 0, 100);
    
    // 矩阵变换
    kmMat4Multiply(&camMat, &camMat, &rotaMat);
    kmMat4Multiply(&camMat, &camMat, &transMat);
    
    // 用最终的矩阵变换相应的点
    kmVec3Transform(¢er, ¢er, &camMat);
    kmVec3Transform(&up, &up, &camMat);
    kmVec3Transform(&eye, &eye, &camMat);
    
    [cam setEyeX:eye.x eyeY:eye.y eyeZ:eye.z];
    [cam setCenterX:center.x  centerY:center.y centerZ:center.z];   
    [cam setUpX:up.x upY:up.y upZ:up.z];
}