VR+全景播放器+头控讲解-01-知识储备
VR+全景播放器+头控讲解-02-创建球体
VR+全景播放器+头控讲解-03-渲染视频
VR+全景播放器+头控讲解-04-滑动手势
VR+全景播放器+头控讲解-05-伸缩画面
VR+全景播放器+头控讲解-06-头控实现
VR+全景播放器+头控讲解-07-分屏技术

本节学习目标

捏合手势如何缩放画面

实现步骤

1.创建捏合手势添加到视图中去,这个视图也是最外层的视图

self.pinchGesture = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(pinchGesture:)];
[view addGestureRecognizer:self.pinchGesture];

2.算法处理,改变Camera属性的xFov ,yFov

   -(void)pinchGesture:(UIPinchGestureRecognizer*)pinchGesture{
    if (pinchGesture.state != UIGestureRecognizerStateEnded &&   pinchGesture.state != UIGestureRecognizerStateFailed) {
      if (pinchGesture.scale != NAN && pinchGesture.scale != 0.0) {
          float scale = pinchGesture.scale - 1;
          if (scale < 0) scale *= (sScaleMax - sScaleMin);
          _currentScale = scale + _prevScale;
          _currentScale = [self validateScale:_currentScale];
          CGFloat valScale = [self validateScale:_currentScale];
          double xFov = CAMERA_FOX * (1-(valScale-1)*0.15);
          double yFov = CAMERA_HEIGHT * (1-(valScale-1)*0.15);
      }
    } else if(pinchGesture.state == UIGestureRecognizerStateEnded){
      _prevScale = _currentScale;
    }
    }
-(float)validateScale:(float)scale{
  if (scale < sScaleMin)
      scale = sScaleMin;
  else if (scale > sScaleMax) scale = sScaleMax;
  return scale;
}

3.改变照相机节点的属性xFov,yFov

self.eyeNode.camera.xFov = xFov;
self.eyeNode.camera.yFov = yFor;

问题:

为什么缩放不是改变球体的半径呢？
答:因为照相机的视野范围不改变,无论球体半径多大,呈现出来的部分都不会改变,如下

理解一下

本节讲解完毕
SceneKit 中文教程